We would like you to find a topic from chapter 1 that you were interested in and search the internet for material on that topic. You might, for example, find people who are doing research on the topic, you might find web pages that discuss the topic, you might find youtube clips that demonstrate something related to the topic, etc. What you find and use is pretty much up to you at this point. But use at least 3 sources.
Once you have completed your search and explorations, we would like you to a) state what your topic is, b) discuss how it fits into the chapter, and c) why you are interested in it. Next, we would like you to take the information you found related to your topic, integrate/synthesize it, and then write about it. At the end, please include working URLs for the three websites.
Once you are done with your post make list of the terms and terminology you used in your post.
By integrating/synthesizing we mean to take what your read/experienced from the internet search (and from the chapter if you like) organize the information into the main themes, issues, info, examples, etc. about your topic and then write about the topic in your own words using that information. This is hard for some people to do - many students write what we refer to as "serial abstracts." They are tempted to talk about the websites rather than the topic proper. They will talk all about website #1, start a new paragraph and talk all about web site #2, start a new paragraph and talk all about web site #3, and then write some kind of conclusion. Serial means one after the other...This what you DON'T want to do!
At first it is a real challenge to get out of the habit of writing "serial abstracts," but we assure you once you get the hang of it it is much easier to write using the integration method. And besides this is the way researchers and scientists write their technical reports and findings - many of you will have to be able to do this for other classes and for jobs that you may eventually be hired for so now is a good time to learn this skill. At this point don't worry about a grade, worry about doing your best to have fun with the topic We will work on citing the sources later....
Let us know if you have any questions.
1a) State what your topic is.
Webers Law.
1b) Discuss how the topic relates to the chapter.
Weber’s Law was one of Ernest Weber’s contributions to psychology. Weber, his ideas, and theories were the focus of the current chapter. His contributions were made known and are still referred to today.
1c) Discuss why you are interested in it.
Weber was subjecting mental events (sensations) to measurement and mathematical formulation. Weber was able to also show that there was not a one to one relationship between changes in the psychical world and the psychological experience of those changes. Lastly he also showed that mental and physical events could be related mathematically. This is interesting because these concepts still hold up today and are still considered, and the research was done in the early 1800’s.
2) Take the information you read or viewed related to your topic, integrate/synthesize it.
Weber’s law also called Weber–Fechner law, historically important psychological law quantifying the perception of change in a given stimulus. The law states that the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus. It has been shown not to hold for extremes of stimulation.
The law was originally postulated to describe researches on weight lifting by the German physiologist Ernst Heinrich Weber in 1834 and was later applied to the measurement of sensation by Weber’s student Gustav Theodor Fechner, who went on to develop from the law the science of psychophysics. By stating a relationship between the psychological and physical worlds, the law indicated to Fechner that there is really only one world, the psychological. To others, the law meant the possibility of a scientific, quantitative psychology. Weber was subjecting mental events (sensations) to measurement and mathematical formulation. Weber was able to also show that there was not a one to one relationship between changes in the psychical world and the psychological experience of those changes. Lastly he also showed that mental and physical events could be related mathematically.
The combined work of Weber and Fechner has been useful, especially in hearing and vision research, and has had an impact on attitude scaling and other testing and theoretical developments.
3) Sources:
http://en.wikipedia.org/wiki/Ernst_Heinrich_Weber
This website gives a little information about Ernest Weber himself, his history.
http://en.wikipedia.org/wiki/Weber%E2%80%93Fechner_law
This website explains the law itself and the mathematics behind it.
http://sunburst.usd.edu/~schieber/coglab/WebersLaw.html
This website I liked about because it gives you some information about the law but also has an interactive experiment to go along with it to help a person better understand the law.
1a) State what your topic is.
Webers Law.
1b) Discuss how the topic relates to the chapter.
Weber’s Law was one of Ernest Weber’s contributions to psychology. Weber was one of the character focuses of the current chapter. His contributions were made known and are still referred to today.
1c) Discuss why you are interested in it.
Weber was subjecting mental events (sensations) to measurement and mathematical formulation. Weber was able to also show that there was not a one to one relationship between changes in the psychical world and the psychological experience of those changes. Lastly he also showed that mental and physical events could be related mathematically. This is interesting because these concepts still hold up today and are still considered, and the research was done in the early 1800’s.
2) Take the information you read or viewed related to your topic, integrate/synthesize it.
Weber’s law also called Weber–Fechner law, historically important psychological law quantifying the perception of change in a given stimulus. The law states that the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus. It has been shown not to hold for extremes of stimulation.
The law was originally postulated to describe researches on weight lifting by the German physiologist Ernst Heinrich Weber in 1834 and was later applied to the measurement of sensation by Weber’s student Gustav Theodor Fechner, who went on to develop from the law the science of psychophysics. By stating a relationship between the psychological and physical worlds, the law indicated to Fechner that there is really only one world, the psychological. To others, the law meant the possibility of a scientific, quantitative psychology. Weber was subjecting mental events (sensations) to measurement and mathematical formulation. Weber was able to also show that there was not a one to one relationship between changes in the psychical world and the psychological experience of those changes. Lastly he also showed that mental and physical events could be related mathematically.
The combined work of Weber and Fechner has been useful, especially in hearing and vision research, and has had an impact on attitude scaling and other testing and theoretical developments.
3) Sources:
http://en.wikipedia.org/wiki/Ernst_Heinrich_Weber
This website gives a little information about Ernest Weber himself, his history.
http://en.wikipedia.org/wiki/Weber%E2%80%93Fechner_law
This website explains the law itself and the mathematics behind it.
http://sunburst.usd.edu/~schieber/coglab/WebersLaw.html
This website I liked about because it gives you some information about the law but also has an interactive experiment to go along with it to help a person better understand the law.
My topic is Fourier Analysis applied to sound. The chapter briefly describes Fourier Analysis as the breakdown of sensory input (such as sound waves) into many constituent sine waves of varying frequency, phase and amplitude. I was interested to learn more about the mathematics behind this analysis, and the process of sound perception. Sound is the product of pressure waves travelling through the air. Because few sounds are “pure tones,” most of what we hear are complex sounds made up of an infinite number of sine and cosine waves. Fourier analysis is the process of mathematically breaking up sound waves into the constituent sine and cosine waves.
It turns out the actual mathematics behind Fourier Analysis are not as interesting to learn about, however today’s computers and software programs make the process much easier than when Fourier first developed it using paper and pencil. First, sound is transformed from the time domain to the frequency domain so that it can be evaluated mathematically. The frequency, phase and amplitude of separate sine waves are then measured. The analysis is more easily understood by looking at frequency and amplitude of sound plotted on a graph. Amplitude refers to the degree of change in a single sine wave, perceived as volume. A higher amplitude, or higher degree of change, represents a louder sound than a wave with a lower amplitude.
The combination of wave frequencies and amplitudes describe the harmony of sound we hear, and also dictates the quality of equipment required to produce the same sound. For example, a trombone is comprised of relatively few, low frequency sound waves, therefore we can easily reproduce the sound of a trombone. Conversely, percussive instruments such as cymbals require high frequency waves, therefore higher quality sound equipment is needed when synthesizing this sound. Our ears naturally perform Fourier analysis by transforming sound into a description of the sound as a combination of its constituent sine waves using frequency, amplitude and phase. This information is transmitted from the cochlea to an area of the brain responsible for sound perception, known as the auditory cortex, by the auditory nerve. The auditory cortex interprets this information as sounds that we hear, understand, and perhaps recognize, then sent to other areas of the brain responsible for responding.
As shown in the animation from the third source, sound perception depends on alertness. Conscious perception allows us to use memory, emotion, and reflex to respond when awake. When we are asleep, sound is still perceived in the auditory cortex, the area of the brain responsible for perceiving sound, however other regions of the brain are not active. We can adapt to observe certain sounds when asleep (a given example is the sound of a baby) and emit a voluntary response, such as tend to the baby’s needs. This also explains how the sudden noise of an alarm clock can wake us. While asleep, the loud complex sound of an alarm is interpreted as a spectrum of sound, the collection of sine waves at varying frequency, phase, and amplitude, then transmits neural signals to the auditory cortex where the signal is organized into sound that we hear. The sudden noise jolts our consciousness, and once we are awake we recognize the sound of an alarm, and respond. Of course, the given response will depend on the individual and their feelings about getting out of bed in the morning.
http://hyperphysics.phy-astr.gsu.edu/hbase/audio/fourier.html
http://www.dataq.com/blog/analysis-software/fft-fast-fourier-transform-waveform-analysis/
http://www.cochlea.org/en/hearing/auditory-brain
Terms: Fourier Analysis, sound, sine wave, frequency, phase, amplitude, volume, neural signal, cochlea, Auditory Nerve, Auditory Cortex, spectrum, auditory perception
My topic is Fourier Analysis applied to sound. The chapter briefly describes Fourier Analysis as the breakdown of sensory input (such as sound waves) into many constituent sine waves of varying frequency, phase and amplitude. I was interested to learn more about the mathematics behind this analysis, and the process of sound perception. Sound is the product of pressure waves travelling through the air. Because few sounds are “pure tones,” most of what we hear are complex sounds made up of an infinite number of sine and cosine waves. Fourier analysis is the process of mathematically breaking up sound waves into the constituent sine and cosine waves.
It turns out the actual mathematics behind Fourier Analysis are not as interesting to learn about, however today’s computers and software programs make the process much easier than when Fourier first developed it using paper and pencil. First, sound is transformed from the time domain to the frequency domain so that it can be evaluated mathematically. The frequency, phase and amplitude of separate sine waves are then measured. The analysis is more easily understood by looking at frequency and amplitude of sound plotted on a graph. Amplitude refers to the degree of change in a single sine wave, perceived as volume. A higher amplitude, or higher degree of change, represents a louder sound than a wave with a lower amplitude.
The combination of wave frequencies and amplitudes describe the harmony of sound we hear, and also dictates the quality of equipment required to produce the same sound. For example, a trombone is comprised of relatively few, low frequency sound waves, therefore we can easily reproduce the sound of a trombone. Conversely, percussive instruments such as cymbals require high frequency waves, therefore higher quality sound equipment is needed when synthesizing this sound. Our ears naturally perform Fourier analysis by transforming sound into a description of the sound as a combination of its constituent sine waves using frequency, amplitude and phase. This information is transmitted from the cochlea to an area of the brain responsible for sound perception, known as the auditory cortex, by the auditory nerve. The auditory cortex interprets this information as sounds that we hear, understand, and perhaps recognize, then sent to other areas of the brain responsible for responding.
As shown in the animation here, sound perception depends on alertness. Conscious perception allows us to use memory, emotion, and reflex to respond when awake. When we are asleep, sound is still perceived in the auditory cortex, the area of the brain responsible for perceiving sound, however other regions of the brain are not active. We can adapt to observe certain sounds when asleep (a given example is the sound of a baby) and emit a voluntary response, such as tend to the baby’s needs. This also explains how the sudden noise of an alarm clock can wake us. While asleep, the loud complex sound of an alarm is interpreted as a spectrum of sound, the collection of sine waves at varying frequency, phase, and amplitude, then transmits neural signals to the auditory cortex where the signal is organized into sound that we hear. The sudden noise jolts our consciousness, and once we are awake we recognize the sound of an alarm, and respond. Of course, the given response will depend on the individual and their feelings about getting out of bed in the morning.
http://hyperphysics.phy-astr.gsu.edu/hbase/audio/fourier.html
http://www.dataq.com/blog/analysis-software/fft-fast-fourier-transform-waveform-analysis/
http://www.cochlea.org/en/hearing/auditory-brain
Terms: Fourier Analysis, sound, sine wave, frequency, phase, amplitude, volume, neural signal, cochlea, Auditory Nerve, Auditory Cortex, spectrum, auditory perception
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses.
It is often used in neuroscience and experimental research. It’s important to note that at such low levels, participants may only detect the stimulus part of the time. Because of this, the absolute threshold is usually defined as the smallest level of a stimulus that a person is able to detect 50 percent of the time. In hearing, the absolute threshold refers to the smallest level of a tone that can be detected by a normal hearing when there are no other interfering sounds present. An example of this could be measuring at what levels a person can detect the ticking of a clock. Younger people generally have a lower absolute threshold for sounds since the ability to detect sounds at the lowest and highest ranges tend to decrease with age. Research shows that the quietest sound that children with normal hearing can detect is about 1,000 hz.
In vision, the absolute threshold refers to the smallest level of light that a participant can detect. For example, determining the absolute threshold for vision might involve measuring the distance at which a participant can detect the presence of a candle flame in the dark. In one classic experiment, researchers found that after controlling for dark adaptation, wavelength, location and stimulus size, the human eye was able to detect a stimulus of 90 photons. For odors, the absolute threshold involves the smallest concentration that a participant is able to smell. An example of this would be to measure what the smallest amount of perfume that a subject is able to smell in a large room. While the absolute threshold is often thought of purely in terms of sensation and perception, a number of factors can play a role including expectations, motivations, and thoughts. The absolute threshold should not be confused with the difference threshold, which is the smallest possible detectable difference between two stimuli.
This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a man using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
There any many different real life examples of absolute threshold. If I can hear a very high pitched noise, but someone else cannot, then the sound is above my own absolute threshold and below the other person's absolute threshold. A good example of this would be the "Mosquito" ringtone. When you have to turn your music all the way down when someone is talking to you and you decide you want to listen to it quietly, turn it up until you can barely hear it and that is your absolute threshold. If a bug is so small that when it lands on you you can't detect it, it is below your absolute threshold. However, if you do detect the bug, it is above your absolute threshold becuase there was enough stimuli to be detected.
A number of different factors can influence the absolute threshold, including the observer's motivations and expectations, and whether the person is adapted to the stimulus. Scientists have discovered that cognitive processes can influence the measurement of the threshold and that it is not as simple as once understood. Psychologists have also studied how different two stimuli have to be in order to be noticed as not being the same. Such an approach involves what are called difference thresholds.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption, neuroscience, experimental research, hearing, tone, interfering sound, hertz, vision, wavelength, eye, photons, concentration, motivations, expectations, sensory, taste, smell, audition senses, touch.
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
I found the topics related to threshold all very interesting, however the section that discussed supertasters really caught my attention. It makes sense that as varied as people are in all other aspects physical that there would be variances in the way they taste foods. In my own personal experience of having four children I can definitely attest that we most certainly taste things differently. Seriously try getting four people to agree on one flavor of ice cream!
It is estimated that supertasters account for 25% of the population, their opposite’s non tasters also 25% and the rest of us “normal” tasters account for half. Some experts believe that the supertaster gene is part of our evolution. They believe that in the past this gene could have acted as a kind of safety for early humans to keep them from consuming foods and toxins that are poisonous.
As I looked further I found that there are some very serious health issues that are associated with supertasters. The sensitivity to bitter foods means that many of the really good-for-you foods like broccoli, spinach are not generally a part of a supertaster’s diet. The bitter taste is much more intense for them, this means that even if they do consume some of these things they load them up with salt and other condiments that are not so healthy. They have a higher risk of cancers especially colon cancer because their diet lacks some of the foods that aid in prevention. It is also interesting that because of their super sense of taste it takes little of the sweet sensation to curb appetites in females. This can make them less likely to have cardiac problems. However men supertasters are drawn to high fat foods which can lead them to increased risk for heart disease.
The test often used to by observers to distinguish the supertasters is a chemical called propylhiouracil (PROP). This chemical will taste very bitter to supertasters. When PROP is given to individuals they are asked to compare the bitterness to another sense such as the degree of sound, this is called cross-modality matching. What I was able to find about PROP is that it is being used by resarchers to predict alcoholism. One study gave PROP to a group of 25 students. The study found that nontasters of PROP were more likely to have just alcoholism in their family. The supertasters were more likely to have both alcoholism and depression in their families. The researchers believe that this suggests that PROP may be useful in finding genetic causes for two types of alcoholism.
Psychology Today: http://www.psychologytoday.com/blog/comfort-cravings/201006/are-you-supertaster-mindless-eating-your-taste-buds
Pub Med: http://www.ncbi.nlm.nih.gov/pubmed/9662078
BBC: http://www.bbc.co.uk/science/humanbody/body/articles/senses/supertaster.shtml
Terms: sensation, PROP, supertasters, nontasters, cross-modality matching, threshold
I found the topics related to threshold all very interesting, however the section that discussed supertasters really caught my attention. It makes sense that as varied as people are in all other aspects physical that there would be variances in the way they taste foods. In my own personal experience of having four children I can definitely attest that we most certainly taste things differently. Seriously try getting four people to agree on one flavor of ice cream!
It is estimated that supertasters account for 25% of the population, their opposite’s non tasters also 25% and the rest of us “normal” tasters account for half. Some experts believe that the supertaster gene is part of our evolution. They believe that in the past this gene could have acted as a kind of safety for early humans to keep them from consuming foods and toxins that are poisonous.
As I looked further I found that there are some very serious health issues that are associated with supertasters. The sensitivity to bitter foods means that many of the really good-for-you foods like broccoli, spinach are not generally a part of a supertaster’s diet. The bitter taste is much more intense for them, this means that even if they do consume some of these things they load them up with salt and other condiments that are not so healthy. They have a higher risk of cancers especially colon cancer because their diet lacks some of the foods that aid in prevention. It is also interesting that because of their super sense of taste it takes little of the sweet sensation to curb appetites in females. This can make them less likely to have cardiac problems. However men supertasters are drawn to high fat foods which can lead them to increased risk for heart disease.
The test often used to by observers to distinguish the supertasters is a chemical called propylhiouracil (PROP). This chemical will taste very bitter to supertasters. When PROP is given to individuals they are asked to compare the bitterness to another sense such as the degree of sound, this is called cross-modality matching. What I was able to find about PROP is that it is being used by resarchers to predict alcoholism. One study gave PROP to a group of 25 students. The study found that nontasters of PROP were more likely to have just alcoholism in their family. The supertasters were more likely to have both alcoholism and depression in their families. The researchers believe that this suggests that PROP may be useful in finding genetic causes for two types of alcoholism.
Psychology Today: http://www.psychologytoday.com/blog/comfort-cravings/201006/are-you-supertaster-mindless-eating-your-taste-buds
Pub Med: http://www.ncbi.nlm.nih.gov/pubmed/9662078
BBC: http://www.bbc.co.uk/science/humanbody/body/articles/senses/supertaster.shtml
Terms: sensation, PROP, supertasters, nontasters, cross-modality matching, threshold
NEURAL FIRING/NEURAL TRANSMISSION/ACTION POTENTIAL
1. My topic is neural firing, and in the process of browsing the information on my topic I decided to talk about action potential in more details.
2. My topic fits into the chapter because it explains how signals are sent and received in the brain. Action potential explains the process in more details.
3. I am interested in this topic because I think I should get a little more familiar with neurology if I am taking this class, which is less theoretical psychology and more biological/physical/chemical psychology.
Neurons are essential in our brain activities, they are in charge of communicating with each other by passing chemical and electrical signals. A neuron is a nerve cell that specializes in transmitting nerve impulses, and a network of neuron builds the nervous system as we know it.
A neuron’s structure contains the axon, dendrite, and cell body. The cell body is where all the metabolic activity happens, the dendrite receives information from other cells, and the axon passes on the information that is received. When the information is being processes, a brief electrical charge travels down the axon, and that’s what we call an action potential.
When a neuron is not receiving or sending any signal to its peer, it is in resting potential, where the neuron holds a negative charge. During this stage, prior to the action potential, the neuron is inactive. When stimulated enough so that the charge reaches a neural threshold the neuron fire, and that is the action potential. After firing, the neuron retreats back to its resting potential until it is stimulated again.
However, between the resting potential and the action potential, there is a refractory period, where the neuron stays inactive doesn’t matter how stimulated it gets. Then, the neuron gets into a relative refractory period where it requires higher stimulation to fire. Finally, the neuron gets back to the normal firing threshold and waits to be stimulated again.
When a neuron fires, it sends messages to the next neuron’s dendrites. The more branches a dendrite has, the more messages that neuron can receive. However, there is no physical connection between neurons; there is a gap between a neuron’s axon and another’s dendrite, we call that gap the synaptic gap. When the action potential reaches the end of the axon, neurotransmitters (message carriers) gets fired from an axon to a dendrite. These neurotransmitters have to travel from one end of the synaptic gap to the other end, where neuroreceptors awaits.
Different neurotransmitters have different receptors that are waiting for them. When neurotransmitters and receptors meet, the neuron gets stimulated and thus the cycle of action potential begins again.
http://www.cliffsnotes.com/sciences/psychology/psychology/psychology-biological-bases-of-behavior/neural-transmission
http://psychology.about.com/od/aindex/g/actionpot.htm
https://www.youtube.com/watch?v=C4Gt322-XxI
TERMS: neurotransmitters, neuroreceptors, receptors, synapses, synaptic gap, axon, dendrite, cell body, action potential, resting potential, refractory period, relative refractory period, threshold, stimulation, signals, nervous system, neuron
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
My topic is the McGurk effect.
This topic fits into the chapter, because it is an example of the process of cross-modality matching, which is discussed in the chapter.
I am interested in this topic, because it highlights a phenomena that continues as a sort of illusion even after one knows that it is simply an illusion.
Simply put, the McGurk effect is the phenomena of seeing one thing and hearing another thing, even though the two perceptual inputs are contradictory of each other. This highlights our use of visual speech information in perception. To test this effect, have you or someone else look at someone's mouth as they repeatedly form the syllable "ba" without actually making any noise. Now, have a recording of someone saying the syllable "ba" playing in the background. After a few repetitions, have the person mouthing the syllable switch to mouthing the syllable "fa" but do not change the recorded audible syllable. Even though the sound does not change, seeing the person mouth the syllable "fa" will cause the person viewing it to hear "fa" instead of "ba" which is actually played. If the viewer closes his or her eyes, they will return to hearing "ba" but they will revert to hearing "fa" as soon as they open their eyes and see the person mouthing that syllable. This effect works regardless of whether or not the viewer is aware of it or how many times the visual stimuli is changed back and forth. The fact that it happens regardless of our awareness of it happening shows just how heavily we rely on visual speech information. This is an example of the brain doing whatever it can to make sense of the chaos in the world. From this rises the question of what is actually reliable in our perception of the world. If something so simple is so hard to overcome, even when one recognizes it is happening, what else in the world could our brains be falsely representing to us?
Terms: McGurk Effect, Cross-Modality Matching, Perception, Visual Speech Information, Stimuli
http://www.faculty.ucr.edu/~rosenblu/VSMcGurk.html
http://auditoryneuroscience.com/McGurkEffect
https://www.youtube.com/watch?v=G-lN8vWm3m0
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
My topic is Santiago Ramón y Cajal and his discovery that axons of neurons are not actually connected to dendrites of other neurons, and rather there are spaces between called synapses. This fits into the chapter because this connection between nerves is what allows sensation to reach the brain in the first place. Without this connection, we would not be able perceive sensation in the first place. I am interested in this topic because I believe this tiny biological function is the basis for sensation and perception as a whole. Along with this, I am very curious to know how
Santiago Ramón y Cajal was able to reach this advancement.
In the late 1800’s, many scientists, specifically histologists, investigated the microscopic make up of tissue. Of this area of study, neurological tissue was the most mysterious. At this point, it was agreed that the nervous system was made up of tightly packed fibrous cell tissues. The divide in the scientific community came when figuring out exactly how the fibers were arranged and how they even functioned. One theory was the reticular theory. Headed by Joseph von Gerlach, this theory stated that nervous tissue was a vast “basket-like” network of cells that are fused together. In 1888, Camillo Golgi, who was another respected and well-known scientist, further backed up this theory. The other theory was known as the Neuron Theory, which was first proposed by a man, named Heinrich Waldeyer, and supported by Cajal. This asserted that nervous tissue was made of separate cells named neurons.
While studying this topic, Golgi developed a revolutionary staining method, which enabled the advancement of neurological science. He discovered that by hardening tissues in a mixture of potassium bichromate and ammonia, and then soaking that tissue in silver nitrate, the cells would be dyed dark. The newly darkened cells were much easier to view underneath a microscope. Today, this method is known as Golgi staining. This method was taken a step further by Cajal in 1887. Cajal soaked the tissue a twice, giving it an even deeper dye. This enhanced the detail at which the neurons could be viewed.
Cajal continued the study of these neurons. In doing so, he was able to lean about the structure of each cell. While he was not responsible for naming the parts of a neuron, it is clear through his descriptions and detailed drawings that he was able to identify such parts as axons and dendrites. In 1888, Cajal was studying the nervous tissue of a chick. He saw that each axon of a neuron would end with grey matter, and then were followed by the beginning of a dendrite. This discovery then led to Cajal’s law of dynamic polarization, which states that information flows uni-directionally through a neuron (Dendrite-Cell Body-Axon). Also due to the observation he made, it was proven that nerve cells are not continuous, but rather contiguous. In layman’s terms, this means that nerve cells work together in close proximity rather than actually being fused together. Santiago Ramón y Cajal received a Nobel Prize in 1906 for his revolutionary findings in the structure of nervous tissue, alongside Camillo Golgi. Today he is known as the father of modern neuroscience.
Sources:
https://www.youtube.com/watch?v=pBd7AJk1drY
http://www.ncbi.nlm.nih.gov/pubmed/17027775
https://neurophilosophy.wordpress.com/2006/08/29/the-discovery-of-the-neuron/
Terms: Histologists; Tissue; Neurological; Fibrous Tissue; Reticular Theory; Neuron Theory; Axon; Dendrite; Cell Body; Law of Dynamic Polarization; Contiguous; Golgi Staining; Potassium Bichromate; Ammonia; Silver Nitrate; Neuroscience
My topic is Santiago Ramón y Cajal and his discovery that axons of neurons are not actually connected to dendrites of other neurons, and rather there are spaces between called synapses. This fits into the chapter because this connection between nerves is what allows sensation to reach the brain in the first place. Without this connection, we would not be able perceive sensation in the first place. I am interested in this topic because I believe this tiny biological function is the basis for sensation and perception as a whole. Along with this, I am very curious to know how
Santiago Ramón y Cajal was able to reach this advancement.
In the late 1800’s, many scientists, specifically histologists, investigated the microscopic make up of tissue. Of this area of study, neurological tissue was the most mysterious. At this point, it was agreed that the nervous system was made up of tightly packed fibrous cell tissues. The divide in the scientific community came when figuring out exactly how the fibers were arranged and how they even functioned. One theory was the reticular theory. Headed by Joseph von Gerlach, this theory stated that nervous tissue was a vast “basket-like” network of cells that are fused together. In 1888, Camillo Golgi, who was another respected and well-known scientist, further backed up this theory. The other theory was known as the Neuron Theory, which was first proposed by a man, named Heinrich Waldeyer, and supported by Cajal. This asserted that nervous tissue was made of separate cells named neurons.
While studying this topic, Golgi developed a revolutionary staining method, which enabled the advancement of neurological science. He discovered that by hardening tissues in a mixture of potassium bichromate and ammonia, and then soaking that tissue in silver nitrate, the cells would be dyed dark. The newly darkened cells were much easier to view underneath a microscope. Today, this method is known as Golgi staining. This method was taken a step further by Cajal in 1887. Cajal soaked the tissue a twice, giving it an even deeper dye. This enhanced the detail at which the neurons could be viewed.
Cajal continued the study of these neurons. In doing so, he was able to lean about the structure of each cell. While he was not responsible for naming the parts of a neuron, it is clear through his descriptions and detailed drawings that he was able to identify such parts as axons and dendrites. In 1888, Cajal was studying the nervous tissue of a chick. He saw that each axon of a neuron would end with grey matter, and then were followed by the beginning of a dendrite. This discovery then led to Cajal’s law of dynamic polarization, which states that information flows uni-directionally through a neuron (Dendrite-Cell Body-Axon). Also due to the observation he made, it was proven that nerve cells are not continuous, but rather contiguous. In layman’s terms, this means that nerve cells work together in close proximity rather than actually being fused together. Santiago Ramón y Cajal received a Nobel Prize in 1906 for his revolutionary findings in the structure of nervous tissue, alongside Camillo Golgi. Today he is known as the father of modern neuroscience.
Sources:
https://www.youtube.com/watch?v=pBd7AJk1drY
http://www.ncbi.nlm.nih.gov/pubmed/17027775
https://neurophilosophy.wordpress.com/2006/08/29/the-discovery-of-the-neuron/
Terms: Histologists; Tissue; Neurological; Fibrous Tissue; Reticular Theory; Neuron Theory; Axon; Dendrite; Cell Body; Law of Dynamic Polarization; Contiguous; Golgi Staining; Potassium Bichromate; Ammonia; Silver Nitrate; Neuroscience
The topic that I decide to further explore was a vague area of thresholds. I find it interesting to learn about the tenacity of our senses and to see the vary limits from one person to the next. As I stated in me previous post I have seen some little experiments done with testing threshold on the skin or with noise so I decided to go out and find some more that may interest the class and help better to explain what they are.
I found one website that was more for kids but it had a great way to set up a few experiments to explain the concept of thresholds. For instance in one of the experiments you are to blind fold a partner and then “poke” them with items like paperclips on different parts of the body in varying distances from each other. What you find when you do the receptors in our skin are NOT distributed in a uniform way around our bodies. Some places, such as our fingers and lips, have more touch receptors than other parts of our body, such as our backs. That's one reason why we are more sensitive to touch on our fingers and face than on our backs. That experiment was just related to touch sensation thresholds. There are other types like with sound that we have discovered that as we age we can no longer hear higher frequencies. That why in grade school that “bat sonar” ringtone was popular because the teacher could not hear it go of in class.
For anyone who would like to test their hearing they can use the second link at the bottom of my post. Another fun and interesting set of thresholds is with tastes. People vary on their degrees of what they can taste. The five main areas of taste we think of are sweet, savory, salty, sour, and bitter. There are many kinds of experiments to use to figure out your own taste threshold as I provided a link for one below. I enjoyed doing this research just because I have had fun in the past studying this area and I like how different the possibilities vary from person to person. Things like age and sex can impact these areas as well. Like I mentioned with the noise frequencies, we know that our hearing decrease with age. Now I want to know why exactly that happens, are there ways to prevent it or restore hearing lose. Why do some people lose their hearing faster than others? Is it genetic, or did they just go to too many scream band concerts when they were young. That is why I enjoy this subject and I hope you find it interesting as well.
Terms: Thresholds, sensation, perception,experiments,
https://faculty.washington.edu/chudler/chtouch.html
http://www.noiseaddicts.com/2009/03/can-you-hear-this-hearing-test/
http://www.sciencebuddies.org/science-fair-projects/project_ideas/HumBio_p013.shtml
The topic that I decide to further explore was a vague area of thresholds. I find it interesting to learn about the tenacity of our senses and to see the vary limits from one person to the next. As I stated in me previous post I have seen some little experiments done with testing threshold on the skin or with noise so I decided to go out and find some more that may interest the class and help better to explain what they are.
I found one website that was more for kids but it had a great way to set up a few experiments to explain the concept of thresholds. For instance in one of the experiments you are to blind fold a partner and then “poke” them with items like paperclips on different parts of the body in varying distances from each other. What you find when you do the receptors in our skin are NOT distributed in a uniform way around our bodies. Some places, such as our fingers and lips, have more touch receptors than other parts of our body, such as our backs. That's one reason why we are more sensitive to touch on our fingers and face than on our backs. That experiment was just related to touch sensation thresholds. There are other types like with sound that we have discovered that as we age we can no longer hear higher frequencies. That why in grade school that “bat sonar” ringtone was popular because the teacher could not hear it go of in class.
For anyone who would like to test their hearing they can use the second link at the bottom of my post. Another fun and interesting set of thresholds is with tastes. People vary on their degrees of what they can taste. The five main areas of taste we think of are sweet, savory, salty, sour, and bitter. There are many kinds of experiments to use to figure out your own taste threshold as I provided a link for one below. I enjoyed doing this research just because I have had fun in the past studying this area and I like how different the possibilities vary from person to person. Things like age and sex can impact these areas as well. Like I mentioned with the noise frequencies, we know that our hearing decrease with age. Now I want to know why exactly that happens, are there ways to prevent it or restore hearing lose. Why do some people lose their hearing faster than others? Is it genetic, or did they just go to too many scream band concerts when they were young. That is why I enjoy this subject and I hope you find it interesting as well.
Terms: Thresholds, sensation, perception, experiments
https://faculty.washington.edu/chudler/chtouch.html
http://www.noiseaddicts.com/2009/03/can-you-hear-this-hearing-test/
http://www.sciencebuddies.org/science-fair-projects/project_ideas/HumBio_p013.shtml
The topic I decided to do further research on is neuroimaging. This topic was discussed in chapter one as an exciting way for neuroscientists to actually see the brain while it is functioning in a living human being. The section covered common types of imaging such as CT scans, MRI's, fMRI's and PET scans. This type of imaging allows researchers to gain further understanding of concepts such as sensation and perception. It gives insight into what parts of the brain are involved when an individual feels a sensation and how our brain perceives and gives meaning to these sensations. I am very interested in this topic because of my growing love for neuroscience. I am fascinated by the brain and all of the amazing functions it performs constantly. I think it is incredible that we now have the ability to see the brain functioning in a living human being. Not only does it help diagnose brain tumors and mental illness, but it is also used for research on what parts of the brain are active when a person is performing a certain activity and what parts of the brain can be associated with addiction and certain emotional stimuli.
In their article, Kahn and Bunge give an overview of neuroimaging techniques and their significant contribution to understanding cognition. When neuroimaging was created it was used to find neuropathies in the brain of patients with cognitive disabilities and to locate brain activation when performing a certain task. CT scans were the first widely used brain imaging technique, and soon after MRI's and fMRI's were created to give an even more detailed image of the structural brain and the activation within it. PET scans indirectly measure neural activity by injecting radioactive tracers into the body to follow heavy blood flow toward areas of the brain highly populated with neurons. fMRI's, one of the newest and most interesting techniques to indirectly measure neural activity has given astounding knowledge to research on mental disorders such as schizophrenia, autism, and depression. Researchers are able to look at the brain of patients to assess whether or not their is an abnormality in the structure of the brain or if there is a part of the brain activated in these individuals that could be accounting for the illness itself. The National Institute of Mental Health uses brain imaging techniques such as the fMRI to study patients with mental illnesses and to provide research for possible treatments. Because of its ability to be used for a variety of neuroscience, the fMRI is currently the most widely used imaging technique. It is easy to access, it is relatively inexpensive and has better temporal and spacial resolution then previous imaging techniques. It functions by the idea that active parts of the brain require more oxygenated blood flow. The imaging lights up in the places where the brain is most activated and where the most oxygenated blood is flowing when performing a certain task. As the parts of the brain that are being utilized light up, researchers are able to find relationships between certain lobes and parts of the brain with certain activities and stimuli. In a youtube video shown below there is a thorough description of different types of imaging as well as what they look like in terms of spatial resolution. Imaging such as a PET scan has less spacial resolution than an fMRI. All of these techniques are incredibly helpful in the research that is done around the world.
Terms: neuroimaging, PET scan, CT scan, MRI, fMRI, sensation, perception, neuroscience
http://bungelab.berkeley.edu/wp-content/uploads/2014/02/Bunge_Kahn_Encycl2009.pdf
http://www.nimh.nih.gov/health/publications/neuroimaging-and-mental-illness-a-window-into-the-brain/index.shtml
https://www.youtube.com/watch?v=N2apCx1rlIQ
I found the topics related to threshold all very interesting, however the section that discussed supertasters really caught my attention. It makes sense that as varied as people are in all other aspects physical that there would be variances in the way they taste foods. In my own personal experience of having four children I can definitely attest that we most certainly taste things differently. Seriously try getting four people to agree on one flavor of ice cream!
It is estimated that supertasters account for 25% of the population, their opposite’s non tasters also 25% and the rest of us “normal” tasters account for half. Some experts believe that the supertaster gene is part of our evolution. They believe that in the past this gene could have acted as a kind of safety for early humans to keep them from consuming foods and toxins that are poisonous.
As I looked further I found that there are some very serious health issues that are associated with supertasters. The sensitivity to bitter foods means that many of the really good-for-you foods like broccoli, spinach are not generally a part of a supertaster’s diet. The bitter taste is much more intense for them, this means that even if they do consume some of these things they load them up with salt and other condiments that are not so healthy. They have a higher risk of cancers especially colon cancer because their diet lacks some of the foods that aid in prevention. It is also interesting that because of their super sense of taste it takes little of the sweet sensation to curb appetites in females. This can make them less likely to have cardiac problems. However men supertasters are drawn to high fat foods which can lead them to increased risk for heart disease.
The test often used to by observers to distinguish the supertasters is a chemical called propylhiouracil (PROP). This chemical will taste very bitter to supertasters. When PROP is given to individuals they are asked to compare the bitterness to another sense such as the degree of sound, this is called cross-modality matching. What I was able to find about PROP is that it is being used by resarchers to predict alcoholism. One study gave PROP to a group of 25 students. The study found that nontasters of PROP were more likely to have just alcoholism in their family. The supertasters were more likely to have both alcoholism and depression in their families. The researchers believe that this suggests that PROP may be useful in finding genetic causes for two types of alcoholism.
Psychology Today: http://www.psychologytoday.com/blog/comfort-cravings/201006/are-you-supertaster-mindless-eating-your-taste-buds
Pub Med: http://www.ncbi.nlm.nih.gov/pubmed/9662078
BBC: http://www.bbc.co.uk/science/humanbody/body/articles/senses/supertaster.shtml
Terms: sensation, PROP, supertasters, nontasters, cross-modality matching, threshold
The topic I picked to research is differences in pain thresholds, along with things that affect an individual’s pain threshold. This relates to the chapter as we read about various types of thresholds in the book. I thought it was interesting how the chapter talked about other kinds of thresholds but did not cover pain thresholds unless you count the section on Cross-Modality Matching and Supertasters and the section in chapter 13 that covers the basics of pain.
The book refers to threshold as the lowest amount of stimuli required to feel the stimulus however: I will use the International Association for the Study of Pains’ definition, “the minimum intensity of a stimulus that is perceived as painful" as the working definition of pain threshold in this post. The Stimuli is the event that causes the pain and the Stimulus is the feeling of pain. Tolerance is “the time that a continuous pain stimulus is tolerated.” Analgesia is defined in the textbook as “decreasing pain sensation during conscious experience.”
One I aspect of pain thresholds I wondered about is whether or not there is a difference from one person’s pain threshold to another person’s. This led me to more than a few websites that questioned whether women or men had a higher pain threshold. It seems the pre-dominate opinion was the women had a higher pain threshold because females are the ones that give birth. However, this is not true according to Jennifer Graham (a professor of bio behavioral health at Penn State). Gram explains that since pain is subjective, it is hard to definitively say wither or not one gender is less resistant to pain for a few reasons. Tolerance and social factors and emotional factors must be taken into account when studying pain.
Even though there isn’t a gendered reason one person feels less pain, I found several sources that say there are several biological factors that impact both sexes. Tolerance is what happens when a person deals with pain enough that the stimulus is no longer as noticeable for the person. This happens because when a person’s the nerves send the message “Oww, it hurts” to the prefrontal cortex. Then the brain responds by sending out a hormone called endogenous opiate that blocks the release/ up take of the neurotransmitter (messages in the form of chemicals) so the message is no longer sent to the brain. If what I just wrote about doesn’t work, analgesia happens. Analgesia is simply explained as the injury loosing sensation if the person feeling the pain is awake. Another way the body deals with pain is a gene code called COMT, which is an enzyme that metabolizes dopamine (the neurotransmitter that sends messages to the brain). This is another method for the body to relieve pain since COMT cuts off the dopamine receptors in brain and the person stops feeling the injury. This third way is not as universal as the first two methods since it relies on a specific DNA gene and not everybody who ever experiences pain will have this particular gene.
Social and emotional factors are interesting and play huge part in how people deal with pain. Pain is something every body feel at some point in their life, but in some cultures one gender is expected to bear it without complaining. One example of this is the idea that “men are tougher than women” and should “Buck up”. Emotional pain is also felt by both sexes and the prefrontal cortex (while in PET scan) lights up just like a physical injury. But there is something different about emotional pain since it is common for emotional responses connected with the long-term suffering that stems from painful memories to cause the person to fear the pain and maybe even feel it again. This is called Secondary Pain affect.
Another interesting idea is that laughing could actually help deal with the physical side (as opposed to the mental side) of pain since self-induced laughing (aka tickling. Don’t ask me to explain how someone is supposed to tickle themselves though) decreases activity on the somatosensory cortex, which stops the pain signals from being received. Laughing is also helpful in dealing with fear (it is a natural response for some people when they are in danger to laugh since it could freak out the source of the fear as well as relax the body physically). This relates to a article written by Jamie L. Rudy and Mary W. Meagher on the topic of fear and anxiety, specifically related to pain. The article explains that pain can feel worse than the stimulus actually is because the person is scared or anxious. Fear and anxiety is very natural reaction to have when injured, but it is important to note that pain can be less extreme if the injured person stays calm. Over all, I started this blog post much less confused about pain thresholds, but it is expected of any top that more a person delves into it: the more complicated and confusing the results are.
http://en.wikipedia.org/wiki/Threshold_of_pain
http://en.wikipedia.org/wiki/International_Association_for_the_Study_of_Pain
http://news.psu.edu/story/141291/2008/11/10/research/probing-question-do-women-have-higher-pain-threshold-men
http://serendip.brynmawr.edu/exchange/node/342
http://onlinelibrary.wiley.com/doi/10.1002/j.1532-2149.2012.00274.x/abstract
http://www.oru.se/PageFiles/21320/Fear%20and%20anxiety.pdf
I decided to do my topic on Absolute Threshold. Absolute Threshold was mentioned in chapter one while talking about what sensation and perception is. I’m really interested in this because I think the whole concept itself is interesting. That each one of us has a different absolute threshold. Sensation is basically the process by which our senses gather information and send it to the brain. The absolute threshold is the point where something becomes noticeable to our senses. A stimuli goes from undetectable to detectable to our senses. This relates to a difference threshold because a difference threshold is about recognizing if a stimulus changes or not. This also relates to signal detection theory because when there is too much going around us stimulus wise, we have to choose what to focus on or ignore. Absolute threshold also relates to sensory adaption because this is when a stimuli remains unchanged for a period of time. All of these relate to absolute threshold because they all fit into the concept of what we do or do not notice stimuli wise. There are many activities that we can use to find our absolute threshold. The youtube video I found has a guy using just his car radio to demonstrate absolute threshold. To some point we can’t hear the music out of his player, but at some point of him adjusting the volume, we can start to hear a faint sound, which is the absolute threshold. There are also many other examples I found on a website that test our taste, smell, touch, vision, and audition senses.
URL: https://www.youtube.com/watch?v=wVhiezByMSU
http://aks.rutgers.edu/aksuww/Psych/305WWW/PsychPhysic/PSYCHPHYSIC.htm
http://allpsych.com/psychology101/sensation/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus, signal detection theory, sensory adaption.
The topic I choose to complete for this weeks topical blog was to look further into positron emission tomography. This relates back to the chapter when talking about the different ways to look at brain activity and the activities of each neuron. It is a way to look into the body and view imaging to see what is going on internally. I found this topic to be very interesting because I have often wondered what makes each part of the brain function and how much does one section of the brain use to think about different topics. I think that over time to see a Positron emission tomography take place during a test would be a neat experience to learn from. I also found it very interesting to see that there were multiple ways of imaging tests that are able to be performed that lead up to different results and have even more than just one way to locate a issue within your given technology just by entering another form of tracer to find out different information.
Looking into the different sources I have learned and found out a lot more information than what I already knew about positron emission tomography. This is a sensitive instrument called a PET camera and is used to look inside the body with a small radioactive drug.Positron emission tomography is a nuclear medicine, functional imaging technique that produces a three-dimensional image of the different functional processes in the body. This test is a imaging test that helps to reveal how your tissues and organs are functioning, it uses a radioactive drug to show this activity.
There is some preparation to having a PET/CT scan, most likely the doctors will ask that the patient have no food or drink before the operation. Upon arrival they will have a radioactive drug injected into their arm and then are placed in a soft lighted room while the drug works it’s way throughout the body. The CT part takes about one minute then the PET scan takes about 30 minutes. Once the scan is complete they will make sure that they have good pictures before sending the patient home while a radiologist takes a look and reads the results of the test.
Often times the tracer is injected, swallowed or inhaled, but this all depends on which organ or body tissue that is used to be studied. The tracer shows the areas of your body that have higher levels of chemical activity which often corresponds to areas of disease and show up as a bright spot on the PET scan. The Pet scan is useful and can be used to detect and evaluate some conditions like cancers, heart disease, and brain disorders. The PET scan does not locate the cancer cell in the body that is why they now use a PET scanner connected with a CT scanner. This way the CT part of the test is able to help better locate the part of the body that the PET scan detects the disease. The PET scan uses a radioactive drug that acts as glucose and glucose is a energy use for a cancer cell, this is how a PET scan is used to detect cancer cells.
http://en.wikipedia.org/wiki/Positron_emission_tomography- this webpage was good for explaining the deffinition in greater detail
http://www.mayoclinic.org/tests-procedures/pet-scan/basics/definition/prc-20014301- this webpage was a great help in explainging the procediure process and more information within the deffinition.
http://www.radiologyinfo.org/en/photocat/gallery3.cfm?pid=1&image=guibertea_PET_CT2.jpg&pg=PET- this video gave me a more complete understanding of the process that the patient has to go through and more about the procedure itself to help me better understand.
Terms: Positron Emission Tomography. Radioactive drug, imaging, organs, tissues, Tracer, disease, neurons, brain activities.
My topic is Cranial Nerves. I will focus on the six cranial nerves discussed in our book.
Cranial Nerves fit into the chapter because cranial nerves are dedicated mainly to sensory and motor systems. As discussed In the chapter, cranial nerves originate in the brain stem and reach sense organs and muscles through openings in the skull.
I am interested in cranial nerves because it is part of the brain. The brain and all of its functions amaze me so much and I would really like to know more about the power the brain has over our bodies. Cranial nerves pass through our bodies and cause us to act in different ways and react in others. There are so many interesting things about the brain and the complexity of it.
There was a ton of information that I found out about cranial nerves. There are 12 cranial nerves which include:
I. Olfactory- The Olfactory nerve is the first of 12 cranial nerves and it contributes to the sense of smell in human beings. The olfactory nerve is also the shortest nerve within the human head. The receptors are located in the mucosa and extends through the ethymoid bone’s cribriform.
II. Optic- The Optic nerve is located in the back of the eye but also the central nervous system. The job of the optic nerve is to transfer visual information from the retina to the vision centers of the brain by electrical impulses.
III. Oculomotor- The third of twelve cranial nerves, the Oculomotor nerve is responsible for eyeball and eyelid movement. This nerve has two separate components which each have their own functions: The somatic motor component and the visceral motor component. The Oculomotor nerve is not responsible for the lateral rectus and the superior oblique muscles.
IV. Trochlear- The only cranial nerve to move dorsally from the brain, making it the longest pathway. The smallest nerve in the eye and services the superior oblique eye muscle and connects to the annular tendon. It helps move the eyes in different directions such as up or down.
VI. Abducens- The abducens nerve controls the eye’s lateral rectus muscle. This is a type of motor nerve that helps turn the eye laterally. By innervating the lateral rectus, the abducent helps pull the eye’s pupil away from the body’s midline.
VII. Auditory (Vestibulocochlear)- This motor nerve connects the inner ear with the brain and transmits impulses that are concerned with hearing and spatial orientation. One reason it is called Vestibulocochlear is because it carries vestibular and cochlear information to the brain.
Each pair of cranial nerves has a separate function sent out from the brain through our bodies to different organs and muscles. There are a total of 12 cranial nerves but the book focused mainly on these six. The other six cranial nerves are trigeminal (V.), facial (VII.), glossopharyngeal (IX.), vagus (X.), spinal accessory (XI.), and hypoglossal (XII.). These six cranial nerves are either exclusively motor accessory or convey both sensory and motor signals. Like the book, I wanted to focus on the studies of perception.
Terms: Cranial nerves, Olfactory (I.), Optic (II.), Oculomotor (III), Trochlear (IV.), Abducent (VI.), Auditory (VIII.), trigeminal (V.), facial (VII.), glossopharyngeal (IX.), vagus (X.), spinal accessory (XI.), and hypoglossal (XII.), perception, sensory motor.
Sources:
http://12cranialnerves.net/
http://www.healthline.com/
http://www.ivyroses.com/HumanBody/Nerves/Cranial-Nerves.php
My topic is Cranial Nerves. I will focus on the six cranial nerves discussed in our book.
Cranial Nerves fit into the chapter because cranial nerves are dedicated mainly to sensory and motor systems. As discussed In the chapter, cranial nerves originate in the brain stem and reach sense organs and muscles through openings in the skull.
I am interested in cranial nerves because it is part of the brain. The brain and all of its functions amaze me so much and I would really like to know more about the power the brain has over our bodies. Cranial nerves pass through our bodies and cause us to act in different ways and react in others. There are so many interesting things about the brain and the complexity of it.
There was a ton of information that I found out about cranial nerves. There are 12 cranial nerves which include:
I. Olfactory- The Olfactory nerve is the first of 12 cranial nerves and it contributes to the sense of smell in human beings. The olfactory nerve is also the shortest nerve within the human head. The receptors are located in the mucosa and extends through the ethymoid bone’s cribriform.
II. Optic- The Optic nerve is located in the back of the eye but also the central nervous system. The job of the optic nerve is to transfer visual information from the retina to the vision centers of the brain by electrical impulses.
III. Oculomotor- The third of twelve cranial nerves, the Oculomotor nerve is responsible for eyeball and eyelid movement. This nerve has two separate components which each have their own functions: The somatic motor component and the visceral motor component. The Oculomotor nerve is not responsible for the lateral rectus and the superior oblique muscles.
IV. Trochlear- The only cranial nerve to move dorsally from the brain, making it the longest pathway. The smallest nerve in the eye and services the superior oblique eye muscle and connects to the annular tendon. It helps move the eyes in different directions such as up or down.
VI. Abducens- The abducens nerve controls the eye’s lateral rectus muscle. This is a type of motor nerve that helps turn the eye laterally. By innervating the lateral rectus, the abducent helps pull the eye’s pupil away from the body’s midline.
VII. Auditory (Vestibulocochlear)- This motor nerve connects the inner ear with the brain and transmits impulses that are concerned with hearing and spatial orientation. One reason it is called Vestibulocochlear is because it carries vestibular and cochlear information to the brain.
Each pair of cranial nerves has a separate function sent out from the brain through our bodies to different organs and muscles. There are a total of 12 cranial nerves but the book focused mainly on these six. The other six cranial nerves are trigeminal (V.), facial (VII.), glossopharyngeal (IX.), vagus (X.), spinal accessory (XI.), and hypoglossal (XII.). These six cranial nerves are either exclusively motor accessory or convey both sensory and motor signals. Like the book, I wanted to focus on the studies of perception.
Terms: Cranial nerves, Olfactory (I.), Optic (II.), Oculomotor (III), Trochlear (IV.), Abducent (VI.), Auditory (VIII.), trigeminal (V.), facial (VII.), glossopharyngeal (IX.), vagus (X.), spinal accessory (XI.), and hypoglossal (XII.), perception, sensory motor.
Sources:
http://12cranialnerves.net/
http://www.healthline.com/
http://www.ivyroses.com/HumanBody/Nerves/Cranial-Nerves.php
I decided to do more research on Pain. There were some interesting topics that I came across, and come to find out pain is still not fully understood in today’s sciences. There is still allot of research being done with pain; this research was a huge in the 1990’s. In the mid-1960s scientists discovered that “the brain could change or modulate the nervous system in response to pain”. Researchers are looking at people’s pain thresholds based on Age, Gender, and Race.
I found that pain begins when nociceptors register disturbance to neighboring tissue. Nociceptors are small thin fibers throughout the body. I researched the different levels of pain and found a sight that claimed there were three different levels of pain.
The first was listed as Experience Pain, which is the perception of prolonged pressure that results into discomfort (pain) after an extended period of time.
The next leave is Tolerable Pain, where the pain increases and the person perceives it as pain. This level is about at the point where if you had a miner headache you would take an aspirin after you finish the task you are doing.
The third level is Intolerable Pain, where you urgently seek out relief as it has triggered your fight or flight response. “Seeking to reduce discomfort is called satisficing, where the person's goals change from achieving something positive to reducing the discomfort”. If the person cannot elevate the pain the body may “shut down” resulting in someone passing out or having a break down.
There were also three different types of pain that they had listed; Emotional, Physical, and Cognitive Pain. Physical pain, being the most immediate and overwhelming form. Emotional pain, where in you have internal feelings that are uncomfortable (examples given were grief, shame, and other forms of self-loathing). Cognitive pain is evident when one has confusion and uncertainty.
As to the effect of who has a higher pain tolerance men or women? Linda LeResche said “The laboratory research seems to indicate that for many kinds -- but not all kinds -- of stimuli, women have a lower tolerance for pain", which directly contradicts the well held belief that women have a higher pain tolerance do to the fact that they may one day have to experience child birth.
I was surprised at how little we really know about why we experience pain, and such with how many different pain medications there are out there on the market. There are probably far better ways to manage pain once we understand what someone’s thresholds are. Those possibilities could result in a non-addictive way to treat those with chronic pain, and possibly revolutionize medications.
Sources
http://abcnews.go.com/Health/PainOverview/story?id=4034879
http://www.medicinenet.com/script/main/art.asp?articlekey=51160
http://changingminds.org/explanations/preferences/pain_thresholds.htm
Terms: threshold, nociceptors, perception, tolerance
The topic I picked to research is differences in pain thresholds, along with things that affect an individual’s pain threshold. This relates to the chapter as we read about various types of thresholds in the book. I thought it was interesting how the chapter talked about other kinds of thresholds but did not cover pain thresholds unless you count the section on Cross-Modality Matching and Supertasters and the section in chapter 13 that covers the basics of pain.
The book refers to threshold as the lowest amount of stimuli required to feel the stimulus however: I will use the International Association for the Study of Pains’ definition, “the minimum intensity of a stimulus that is perceived as painful" as the working definition of pain threshold in this post. The Stimuli is the event that causes the pain and the Stimulus is the feeling of pain. Tolerance is “the time that a continuous pain stimulus is tolerated.” Analgesia is defined in the textbook as “decreasing pain sensation during conscious experience.”
One I aspect of pain thresholds I wondered about is whether or not there is a difference from one person’s pain threshold to another person’s. This led me to more than a few websites that questioned whether women or men had a higher pain threshold. It seems the pre-dominate opinion was the women had a higher pain threshold because females are the ones that give birth. However, this is not true according to Jennifer Graham (a professor of bio behavioral health at Penn State). Gram explains that since pain is subjective, it is hard to definitively say wither or not one gender is less resistant to pain for a few reasons. Tolerance and social factors and emotional factors must be taken into account when studying pain.
Even though there isn’t a gendered reason one person feels less pain, I found several sources that say there are several biological factors that impact both sexes. Tolerance is what happens when a person deals with pain enough that the stimulus is no longer as noticeable for the person. This happens because when a person’s the nerves send the message “Oww, it hurts” to the prefrontal cortex. Then the brain responds by sending out a hormone called endogenous opiate that blocks the release/ up take of the neurotransmitter (messages in the form of chemicals) so the message is no longer sent to the brain. If what I just wrote about doesn’t work, analgesia happens. Analgesia is simply explained as the injury loosing sensation if the person feeling the pain is awake. Another way the body deals with pain is a gene code called COMT, which is an enzyme that metabolizes dopamine (the neurotransmitter that sends messages to the brain). This is another method for the body to relieve pain since COMT cuts off the dopamine receptors in brain and the person stops feeling the injury. This third way is not as universal as the first two methods since it relies on a specific DNA gene and not everybody who ever experiences pain will have this particular gene.
Social and emotional factors are interesting and play huge part in how people deal with pain. Pain is something every body feel at some point in their life, but in some cultures one gender is expected to bear it without complaining. One example of this is the idea that “men are tougher than women” and should “Buck up”. Emotional pain is also felt by both sexes and the prefrontal cortex (while in PET scan) lights up just like a physical injury. But there is something different about emotional pain since it is common for emotional responses connected with the long-term suffering that stems from painful memories to cause the person to fear the pain and maybe even feel it again. This is called Secondary Pain affect.
Another interesting idea is that laughing could actually help deal with the physical side (as opposed to the mental side) of pain since self-induced laughing (aka tickling. Don’t ask me to explain how someone is supposed to tickle themselves though) decreases activity on the somatosensory cortex, which stops the pain signals from being received. Laughing is also helpful in dealing with fear (it is a natural response for some people when they are in danger to laugh since it could freak out the source of the fear as well as relax the body physically). This relates to a article written by Jamie L. Rudy and Mary W. Meagher on the topic of fear and anxiety, specifically related to pain. The article explains that pain can feel worse than the stimulus actually is because the person is scared or anxious. Fear and anxiety is very natural reaction to have when injured, but it is important to note that pain can be less extreme if the injured person stays calm. Over all, I started this blog post much less confused about pain thresholds, but it is expected of any top that more a person delves into it: the more complicated and confusing the results are.
Terms pain thresholds, Cross-Modality Matching, Supertasters, threshold , International Association for the Study of Pains’ , Stimuli, Tolerance, Stimulus, Analgesia, prefrontal cortex, endogenous opiate , sensation, gene code , COMT, enzyme, metabolizes, DNA, PET, Secondary Pain affect, somatosensory cortex.
http://en.wikipedia.org/wiki/Threshold_of_pain
http://en.wikipedia.org/wiki/International_Association_for_the_Study_of_Pain
http://news.psu.edu/story/141291/2008/11/10/research/probing-question-do-women-have-higher-pain-threshold-men
http://serendip.brynmawr.edu/exchange/node/342
http://onlinelibrary.wiley.com/doi/10.1002/j.1532-2149.2012.00274.x/abstract
http://www.oru.se/PageFiles/21320/Fear%20and%20anxiety.pdf
The topic I picked to research is differences in pain thresholds, along with things that affect an individual’s pain threshold. This relates to the chapter as we read about various types of thresholds in the book. I thought it was interesting how the chapter talked about other kinds of thresholds but did not cover pain thresholds unless you count the section on Cross-Modality Matching and Supertasters and the section in chapter 13 that covers the basics of pain.
The book refers to threshold as the lowest amount of stimuli required to feel the stimulus however: I will use the International Association for the Study of Pains’ definition, “the minimum intensity of a stimulus that is perceived as painful" as the working definition of pain threshold in this post. The Stimuli is the event that causes the pain and the Stimulus is the feeling of pain. Tolerance is “the time that a continuous pain stimulus is tolerated.” Analgesia is defined in the textbook as “decreasing pain sensation during conscious experience.”
One I aspect of pain thresholds I wondered about is whether or not there is a difference from one person’s pain threshold to another person’s. This led me to more than a few websites that questioned whether women or men had a higher pain threshold. It seems the pre-dominate opinion was the women had a higher pain threshold because females are the ones that give birth. However, this is not true according to Jennifer Graham (a professor of bio behavioral health at Penn State). Gram explains that since pain is subjective, it is hard to definitively say wither or not one gender is less resistant to pain for a few reasons. Tolerance and social factors and emotional factors must be taken into account when studying pain.
Even though there isn’t a gendered reason one person feels less pain, I found several sources that say there are several biological factors that impact both sexes. Tolerance is what happens when a person deals with pain enough that the stimulus is no longer as noticeable for the person. This happens because when a person’s the nerves send the message “Oww, it hurts” to the prefrontal cortex. Then the brain responds by sending out a hormone called endogenous opiate that blocks the release/ up take of the neurotransmitter (messages in the form of chemicals) so the message is no longer sent to the brain. If what I just wrote about doesn’t work, analgesia happens. Analgesia is simply explained as the injury loosing sensation if the person feeling the pain is awake. Another way the body deals with pain is a gene code called COMT, which is an enzyme that metabolizes dopamine (the neurotransmitter that sends messages to the brain). This is another method for the body to relieve pain since COMT cuts off the dopamine receptors in brain and the person stops feeling the injury. This third way is not as universal as the first two methods since it relies on a specific DNA gene and not everybody who ever experiences pain will have this particular gene.
Social and emotional factors are interesting and play huge part in how people deal with pain. Pain is something every body feel at some point in their life, but in some cultures one gender is expected to bear it without complaining. One example of this is the idea that “men are tougher than women” and should “Buck up”. Emotional pain is also felt by both sexes and the prefrontal cortex (while in PET scan) lights up just like a physical injury. But there is something different about emotional pain since it is common for emotional responses connected with the long-term suffering that stems from painful memories to cause the person to fear the pain and maybe even feel it again. This is called Secondary Pain affect.
Another interesting idea is that laughing could actually help deal with the physical side (as opposed to the mental side) of pain since self-induced laughing (aka tickling. Don’t ask me to explain how someone is supposed to tickle themselves though) decreases activity on the somatosensory cortex, which stops the pain signals from being received. Laughing is also helpful in dealing with fear (it is a natural response for some people when they are in danger to laugh since it could freak out the source of the fear as well as relax the body physically). This relates to a article written by Jamie L. Rudy and Mary W. Meagher on the topic of fear and anxiety, specifically related to pain. The article explains that pain can feel worse than the stimulus actually is because the person is scared or anxious. Fear and anxiety is very natural reaction to have when injured, but it is important to note that pain can be less extreme if the injured person stays calm. Over all, I started this blog post much less confused about pain thresholds, but it is expected of any top that more a person delves into it: the more complicated and confusing the results are.
Terms pain thresholds, Cross-Modality Matching, Supertasters, threshold , International Association for the Study of Pains’ , Stimuli, Tolerance, Stimulus, Analgesia, prefrontal cortex, endogenous opiate , sensation, gene code , COMT, enzyme, metabolizes, DNA, PET, Secondary Pain affect, somatosensory cortex.
http://en.wikipedia.org/wiki/Threshold_of_pain
http://en.wikipedia.org/wiki/International_Association_for_the_Study_of_Pain
http://news.psu.edu/story/141291/2008/11/10/research/probing-question-do-women-have-higher-pain-threshold-men
http://serendip.brynmawr.edu/exchange/node/342
http://onlinelibrary.wiley.com/doi/10.1002/j.1532-2149.2012.00274.x/abstract
http://www.oru.se/PageFiles/21320/Fear%20and%20anxiety.pdf
I found the topics related to threshold all very interesting, however the section that discussed supertasters really caught my attention. It makes sense that as varied as people are in all other aspects physical that there would be variances in the way they taste foods. In my own personal experience of having four children I can definitely attest that we most certainly taste things differently. Seriously try getting four people to agree on one flavor of ice cream!
It is estimated that supertasters account for 25% of the population, their opposite’s non tasters also 25% and the rest of us “normal” tasters account for half. Some experts believe that the supertaster gene is part of our evolution. They believe that in the past this gene could have acted as a kind of safety for early humans to keep them from consuming foods and toxins that are poisonous.
As I looked further I found that there are some very serious health issues that are associated with supertasters. The sensitivity to bitter foods means that many of the really good-for-you foods like broccoli, spinach are not generally a part of a supertaster’s diet. The bitter taste is much more intense for them, this means that even if they do consume some of these things they load them up with salt and other condiments that are not so healthy. They have a higher risk of cancers especially colon cancer because their diet lacks some of the foods that aid in prevention. It is also interesting that because of their super sense of taste it takes little of the sweet sensation to curb appetites in females. This can make them less likely to have cardiac problems. However men supertasters are drawn to high fat foods which can lead them to increased risk for heart disease.
The test often used to by observers to distinguish the supertasters is a chemical called propylhiouracil (PROP). This chemical will taste very bitter to supertasters. When PROP is given to individuals they are asked to compare the bitterness to another sense such as the degree of sound, this is called cross-modality matching. What I was able to find about PROP is that it is being used by resarchers to predict alcoholism. One study gave PROP to a group of 25 students. The study found that nontasters of PROP were more likely to have just alcoholism in their family. The supertasters were more likely to have both alcoholism and depression in their families. The researchers believe that this suggests that PROP may be useful in finding genetic causes for two types of alcoholism.
Psychology Today: http://www.psychologytoday.com/blog/comfort-cravings/201006/are-you-supertaster-mindless-eating-your-taste-buds
Pub Med: http://www.ncbi.nlm.nih.gov/pubmed/9662078
BBC: http://www.bbc.co.uk/science/humanbody/body/articles/senses/supertaster.shtml
Terms: sensation, PROP, supertasters, nontasters, cross-modality matching, threshold
The topic I chose is Psychophysics and the psychophysical approach to perception. Psychophysics is the use of quantitative methods to measure relationships between stimuli (physics) and the subjects. This is what I found most interesting. I was also interested in Top-down processing and I wanted to incorporate that also in this blog post.
First of all, Psychophysics is still being researched to this day.There is in fact a journal called "Attention, Perception, & Psychophysics" is the official journal of the Psychonomic Society. It spans all areas of research in sensory processes, perception, attention, and psychophysics. Most articles published are reports of experimental work; the journal also presents theoretical, integrative, and evaluative reviews. Commentary on issues of importance to researchers appears in a special section of the journal. It was founded in 1966 as "Perception & Psychophysics", the journal assumed its present name in 2009.
Next subject within psychophysics is Visual psychophysics.
Vision is one of the most active areas in biomedical research, and visual psychophysical techniques are a foundational methodology for this research enterprise. Visual psychophysics, which studies the relationship between the physical world and human behavior, is a classical field of study that has widespread applications in modern vision science. Bridging the gap between theory and practice, this textbook provides a comprehensive treatment of visual psychophysics, teaching not only basic techniques but also sophisticated data analysis methodologies and theoretical approaches. It begins with practical information about setting up a vision lab and goes on to discuss the creation, manipulation, and display of visual images; timing and integration of displays with measurements of brain activities and other relevant techniques; experimental designs; estimation of behavioral functions; and examples of psychophysics in applied and clinical settings.
There is a lab in New Zealand Our main research interest is in psychophysical methodology, including measures of detectability, multi-event and multi-dimensional tasks, reducing the effects of observer inconsistency, evaluating correct and incorrect decisions (the Type 2 task), and the development of algorithms for these new methods.
The is a whole vast of software that is use today. The story of software development for psychophysics – like any other story of software development – is one of continuously reinventing the wheel. Hundreds of laboratories have set up powerful facilities. When they started out, the software was mostly tied to specific hardware, perhaps custom designed or not easily available. This has changed quite a bit and hardware dependency is less of a problem today. But nowadays operating system dependency can be an equal hindrance. The three platforms for psychophysical experimentation, PC, Macintosh and Unix, still are the focus of often separate user communities. Back in the 90s, however, Denis Pelli has started to turn the wheel by giving an inspiring example of sharing when he made available his Video Tool box, a highly stable, well supported software basis for visual psychophysics on the Macintosh. The Video Tool box had paved the way for the use of high-level languages like Matlab or Python and is the basis for the Psych tool box which has finally led to a convergence of platforms. Today there are systems in many high level languages. The aim with this web page is to contribute to cooperation by bringing together the developers of software and their users.
https://bakerdh.wordpress.com/2011/04/28/visual-psychophysics-for-beginners/
http://visionscience.com/documents/strasburger/strasburger.html
http://www.springer.com/psychology/cognitive+psychology/journal/13414
Terms: Perception, Psychophysics, Top-down processing, stimuli, subject, quantitative methods, psychology, congitive psychology, research, reviews, integrative, theoretical reviews, researchers, journal, Psychonomic, experimental, sensory processes, attention, vision psychophysics, biomedical, human behavior, creation, manipulation, and display of visual images; timing, integration, measurements, brain activities, Denis Pelli, MetLab, Python, dependency.
My topic is Fourier Analysis applied to sound. The chapter briefly describes Fourier Analysis as the breakdown of sensory input (such as sound waves) into many constituent sine waves of varying frequency, phase and amplitude. I was interested to learn more about the mathematics behind this analysis, and the process of sound perception. Sound is the product of pressure waves travelling through the air. Because few sounds are “pure tones,” most of what we hear are complex sounds made up of an infinite number of sine and cosine waves. Fourier analysis is the process of mathematically breaking up sound waves into the constituent sine and cosine waves.
It turns out the actual mathematics behind Fourier Analysis are not as interesting to learn about, however today’s computers and software programs make the process much easier than when Fourier first developed it using paper and pencil. First, sound is transformed from the time domain to the frequency domain so that it can be evaluated mathematically. The frequency, phase and amplitude of separate sine waves are then measured. The analysis is more easily understood by looking at frequency and amplitude of sound plotted on a graph. Amplitude refers to the degree of change in a single sine wave, perceived as volume. A higher amplitude, or higher degree of change, represents a louder sound than a wave with a lower amplitude.
The combination of wave frequencies and amplitudes describe the harmony of sound we hear, and also dictates the quality of equipment required to produce the same sound. For example, a trombone is comprised of relatively few, low frequency sound waves, therefore we can easily reproduce the sound of a trombone. Conversely, percussive instruments such as cymbals require high frequency waves, therefore higher quality sound equipment is needed when synthesizing this sound. Our ears naturally perform Fourier analysis by transforming sound into a description of the sound as a combination of its constituent sine waves using frequency, amplitude and phase. This information is transmitted from the cochlea to an area of the brain responsible for sound perception, known as the auditory cortex, by the auditory nerve. The auditory cortex interprets this information as sounds that we hear, understand, and perhaps recognize, then sent to other areas of the brain responsible for responding.
As shown in the animation here, sound perception depends on alertness. Conscious perception allows us to use memory, emotion, and reflex to respond when awake. When we are asleep, sound is still perceived in the auditory cortex, the area of the brain responsible for perceiving sound, however other regions of the brain are not active. We can adapt to observe certain sounds when asleep (a given example is the sound of a baby) and emit a voluntary response, such as tend to the baby’s needs. This also explains how the sudden noise of an alarm clock can wake us. While asleep, the loud complex sound of an alarm is interpreted as a spectrum of sound, the collection of sine waves at varying frequency, phase, and amplitude, then transmits neural signals to the auditory cortex where the signal is organized into sound that we hear. The sudden noise jolts our consciousness, and once we are awake we recognize the sound of an alarm, and respond. Of course, the given response will depend on the individual and their feelings about getting out of bed in the morning.
http://hyperphysics.phy-astr.gsu.edu/hbase/audio/fourier.html
http://www.dataq.com/blog/analysis-software/fft-fast-fourier-transform-waveform-analysis/
http://www.cochlea.org/en/hearing/auditory-brain
Terms: Fourier Analysis, sound, sine wave, frequency, phase, amplitude, volume, neural signal, cochlea, Auditory Nerve, Auditory Cortex, spectrum, auditory perception
A) Supertasters
B) This fits into the chapter because it is described in the section of Scaling Methods and Supertasters. Supertaster is how a person perceives a taste in a more extreme kind of way.
C) I am interested in this because it makes me wonder how they perceive the tastes of different kinds of food.
Synthesis
People can fall into three different categories. These are supertasters, meduim tasters, and nontasters. There are about 25 percent of the population that is a super taster, 50 percent that is a meduim or normal taster, and 25 percent that is a nontaster.
This all depends on a persons sesitivity level to the chemical PROP. For a nontaster there is no flavor, for a medium taster it is unpleasant or bitter, and for a supertaster it is extremely bitter.
Unfortunately, it's not good to be a supertaster and have a higher sense to taste. Supertasters are sensitive to bitter foods and they perceive extreme bitterness. Supertassters find normal foods extremely bitter. Things such as coffee, beer, and Brussels sprouts are extremely bitter. They find that things such as cake and ice cream are to rich, and foods like chili peppers are to hot. They usually will keep away from food that are salty sugary, or fatty. They will also keep away from fruits and vegetables because they find the taste of flavornoids very bitter. Some supertasters are food adventurous and others are not. Some seem to be able to modify or better their perception of the taste.
Someone who is a supertasters tends to have more taste buds than others. They can have up to twice as many as normal. This is a genetic trait that they have. The more taste buds that they have the more extreme they will perceive the taste of foods. In conclusion it would be unfortunate to be a supertaster and have to avoid certain foods because you find them bitter.
http://health.howstuffworks.com/mental-health/human-nature/perception/taste4.htm
https://www.youtube.com/watch?v=kyrIxAXZISc
http://www.bbc.co.uk/science/humanbody/body/articles/senses/supertaster.shtml
Terms: Supertaster, Medium taster, Nontaster, Gene, Perceive, PROP, Flavornoids, Sensitivity, Taste buds.
I found the thresholds topic very interesting in this chapter. The “Commonsense Absolute Thresholds” table in this chapter caught my eye in particular. This chapter gave an overview of what really is sensation and perception.
There are many thresholds that we use everyday; the two-point threshold, JND threshold and the difference threshold. Not just the methods themselves, but the researchers involved on the discovery sparked my curiosity. The definition of the two-point threshold is the smallest separation at which two points applied simultaneously to the skin can be distinguished from one. This method of measurement can be very helpful in detecting nerve damage. The second threshold is the JND threshold. (Just Noticeable Difference) The just noticeable difference (JND), also known as the difference threshold, is the minimum level of stimulation that a person can detect 50-percent of the time. For example, if you were asked to hold two objects of different weights, the just noticeable difference would be the minimum weight difference between the two that you could sense half of the time. Marketing companies use JND threshold a lot in the strategies of marketing. Just by making something slightly different, can make the difference in buying that product or not.
I never really thought of thresholds as part of the psychology field. When I felt something painful, I more or less thought it was my nervous system telling my brain that something is wrong. The key is finding which nerve receptors are responsible and why. I did not realize so many steps are taking by our bodies automatically. There are many stages that happen, (often very quickly) when it comes to pain. For instance, when you put your hand on a electric stove top. At first, we feel warmth from the surface, we perceive this as a good feeling, next the longer we hold our hand on that surface, the more uncomfortable the sensation. After just a short time, we feel pain and quickly remove our hand from the heat source. I have always found it interesting that people decades and centuries before us, had to find this out the hard way. From their experiments, they have formed methods to which we still use today. For example, Webbers Law and Fechners Law.
References:
https://www.youtube.com/watch?v=S21VW2u7U50
https://www.youtube.com/watch?v=su007u1LgXg
https://www.youtube.com/watch?v=wVhiezByMSU
Terms: Fechner's Law, Webbers Law, JND threshold, absolute threshold, two-point threshold, methods, pain, threshold, sensation, perception, experiments, psychology, nerve receptors
I’m choosing to look further into the topics of panpsychism and materialism. Near the beginning of the chapter both these topics were briefly mentioned. I am interested in both but more importantly panpsychism. The idea itself is completely far out but I enjoy pondering these sorts of things.
Materialism is the notion that everything is made up of physical elements. Basically everything can be explained through physics, chemistry and biology but ultimately physics. Therefor, anything that happens mentally is a result of fundamental laws of nature. So with this in mind, our perceived self or our inner experience is also a result of physical components working together. The real question is, where does consciousness really come from? Where is the distinction between our “soul” or self and the workings of our neuroanatomy? Unfortunately we do not know. In one of the articles I picked, it was said that we are only certain that our own consciousness exists simply because we can think about it ourselves. As Rene DesCartes states, “I think, therefor I am.” The funny thing is that we cannot be 100% certain that other people are necessarily conscious. This concept might seem funny but its true. There is no way of knowing how other people perceive and how their reality is. Reality of course only exists as a perception in your mind.
So, our consciousness could very well be an illusion. So who is to say that dogs aren’t conscious? or ants? or even your computer?? Yes, it is not outside the realm of possibility that phones or computers could have feelings. This is yet another ridiculous idea that seems like science fiction (2001: A Space Odyssey) but the idea of a HAL 9000 being real could be somewhere in the future.
I know this blog isn’t specifically about the background of materialism or panpsychism but it is definitely inspired by it.
Terms: materialism, panpsychism, consciousness, neuroanatomy
http://www.theguardian.com/science/2015/jan/21/-sp-why-cant-worlds-greatest-minds-solve-mystery-consciousness
http://www.britannica.com/EBchecked/topic/369034/materialism
http://www.scientificamerican.com/article/is-consciousness-universal/
I chose to do my blog topic over "absolute thresholds" I find this interesting because it is something that we all experience constantly throughout our daily routine, however, it isn't something we think about often. Understanding the process is extremely interesting to me.
Absolute thresholds are described as a kind of sensory threshold, which is the smallest detectable level of stimulus. One website gave an example that stated that when we place our hand on something hot we don't often notice it is hot until it is a certain level of heat; when it reaches this level and our brain in notified of the heat it tells us that it is to hot to withstand and to remove our hand from the hot object. This point would be our absolute threshold.
I also learned in my research of the topic that any change that we notice can be considered the absolute threshold not just the feeling or sensation of something. We can test this theory by using light to discover the point at which we actually notice the light; and other examples. It was stated that although the concept of the absolute threshold is useful it doesn't truly exist. "While the absolute threshold is a useful concept, it does not exist in reality. That is, on one occasion, an individual might be unable to detect a certain faint light."
I think my favorite way to define the absolute threshold would be that; absolute threshold is the smallest level of energy required by an external stimulus to be detectable by the human senses, including vision, hearing, taste, smell and touch. I like this definition because it incorporates all the ways in which you can experience that absolute threshold. It also states that it is an external source which effects us.
Overall I like learning about absolute thresholds I find it interesting and it is simple to think of multiple examples in which I experience daily.
Read more: Absolute Threshold - Person, Light, Detect, and Stimulus - JRank Articles http://psychology.jrank.org/pages/4/Absolute-Threshold.html#ixzz3PrZbbHMd
http://psychology.jrank.org/pages/4/Absolute-Threshold.html
http://education-portal.com/academy/lesson/absolute-threshold-examples-definition-quiz.html
https://www.boundless.com/psychology/textbooks/boundless-psychology-textbook/sensation-and-perception-5/sensation-37/absolute-thresholds-158-12693/
Terms: Absolute threshold, sensation, perception, stimuli, difference threshold, stimulus.
my post in unfortunately late getting done. like many others I am interested in absolute threshold. This seems like a unbelievable topic because of how wide of a range that it can cover. not only with pain threshold but I also think of it as a the breaking point that each of us have. I plan to become a police officer and this topic seems to fit in well with it. do to that each officer has a different pain and tolerance level. a way pain level has been significant to me is that I have dislocated my shoulder twice and the second time didn't hurt nearly as much as the 1st time did. I think that the more pain a body goes through the more it can take over time. Its just like it is with alcohol. the more you drink over time the more you can hold.
http://en.wikipedia.org/wiki/Absolute_threshold
http://psychology.about.com/od/glossaryfromatoz/g/absolutethresh.htm
http://education-portal.com/academy/lesson/absolute-threshold-examples-definition-quiz.html
Absolute threshold is interesting to me because it covers such a wide range of stimuli and because the threshold can be different for everybody. It is important to think about when we think about both sensation – the stimulus – and perception – our ability to detect. Studies have been done with vision, hearing and odor. An absolute threshold is the minimum intensity of a stimulus that can be detected 50% of the time or, stated another way, the smallest detectable level of a stimulus. At such low levels, the stimulus will be detected by a subject only half of the time. But it is not absolute across subjects, since it can be influenced by the subject’s motivations and expectations, cognitive processes and whether the subject is adapted to the stimulus. So an absolute threshold is absolute only with respect to one particular subject. For example, children will hear lower tones than adults, because the ability to detect high and low sounds decreases with age.
Another article defines absolute threshold as the smallest level of energy required by the stimulus to be detectable to the human senses. Stimuli at or above the absolute threshold are called supraliminal. For the princess in the story the Princess and the Pea, a pea under her mattress was supraliminal for her, proving her royal status.
Terms: sensation, perception, stimulus, subject, absolute threshold, supraliminal, motivations, cognitive processes, adapted
1A: State what your topic is: Neuroimaging
1B: Discuss how the topic is related to the chapter: This topic was relevant into this chapter because it was stated in the chapter that neuroscientists are no at the highest peek of their research lives to study the brain in many different ways than they ever could before because of the help of technology and great researchers.
1C: Discuss why you might be interested in this: I am interested in this particular topic because at one point, we actually had to put people asleep for people to access their brain and it actually gave danger to those individuals and in some occasions, they weren't able to come back to life, and these people weren't normal people, these people were individuals who are committed in the mental hospitals by the states, people who have no family members to take care of them or help them with their rights to be experimented. but now we're at the point in time where we don't have to force anyone to do that, we don't have to put them to sleep, they can actually be doing something simple and we could actually get inside of their brain and see what nerves or transmitters are being activated to do whatever activity that is that they are doing, these technologies are as effective as we can ever get them to be, Example, MRI scans, fMRI, PET scan, CT scans and so on.
2. Take the information and integrate/synthesize it.
As we can see, i am very impressed and excited at the same time to be able to live through this era and get to see all of the cool things first hand. From the previous times, CT scans were the ones that were used mostly, they saw things, at the time they were probably the most accurate thing that they can use to see images from the brain, but as time pass by, researchers and inventors found ways to make it easier for doctors and researchers to look at the brain. I believe that it's a great thing that we can now look into the brain and see the different areas of it being trigger differently, knowing what or which side is being triggered and by what is such a great thing to see. On a more living skill based of these amazing discoveries, i believe that it's truly a blessing to be able to see the cells that are affected by an illness or a disease, i think that it's great when you can have an fMRI look into some part of your brain and see what is causing the activities that are going on during that process. Not only did the articles stated that with these technologies being available to us, they've also helped us saved lives, prevent illness from getting to far a head and also help us manipulate some activities in the brain, not only do they test a normal brain, they also do alot of research with these materials on abnormative brains as well, much more than a normal brain because they want to be able to understand what it is that's causing the abnormalities. In a video i saw via youtube, it showed different types of brain, it was a brain of someone with autism, brain thats affected by a illness, brain that's been damaged by an accident, and also a brain that's been around for 4,000 years, fried in it's own juice and it's recorded and compared to a normal brain. i think those type of things are very fascinating, just being able to have those options, to furthering our knowledge about things that we once dreamed to knowing or doing, to helping a family from going through a tough time because of their loved one being treated with illness that could've been prevented
PET scan traces the activity of the brain that are going on at that movement.
fMRI and MRI: are easily the ones that gives us a vivid image of what a brain is, transmitters etc.
CT scans were the first ones that we used to access to that version of the brain period. i believe that all of these items are great, and we put them in good use today and without of a doubt they're helping us each and everyday.
Terms: Sensation, CT Scan, MRI fMRI, PET scan, illness, neuroimaging, NeuroScience
http://neuroimages.tumblr.com/
http://www.journals.elsevier.com/neuroimage/call-for-papers/special-issue-on-neuroimaging-mechanisms-of-behavior-change/
http://www.journals.elsevier.com/neuroimage/call-for-papers/effects-of-physical-and-cognitive-activity-on-brain-structur/
I chose thresholds as my topic. Throughout the chapter we talk about the thresholds, what they are, and how they are used with our senses. This is interesting to me because its something we have always heard about but have never gone in depth about throughout other psychology courses.
Searching online I found that there are four different types of thresholds. Those are Absolute, Recognition, differential, and terminal. In general a threshold is the point to where you can see, hear, feel, your senses. Such as with hearing, the threshold is the quietest point you can hear or the highest pitch you can hear.
Sources.
http://en.wikipedia.org/wiki/Sensory_threshold
http://users.ipfw.edu/abbott/120/thresholds.html
http://www.slideshare.net/chauncy/sensation-and-perception