What I would like you to do is to read the chapter in your text about on from Sensation, Perception, & Attention. Next find a related topic that you are 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. I would like you to use quality informative website though.
Once you have completed your search and explorations, I would like you to say what your topic is, how exactly it fits into the chapter, and why you are interested in it. Next, I would like you to take the information you found related to your topic, integrate/synthesize it, and then write about it in an informative manner so the reader will learn about the topic through your writings (not by referring them to a website) . At the end, please include working URLs for the websites used.
Please make sure you use the terms, terminology and concepts you have learned so far in the class. It should be apparent from reading your post that you are a college student well underway in a course in psychology.
Please use spaces between your paragraphs to make your post easier to read - thanks in advance
Let me know if you have any questions.
Previewing your Comment
bsue07 | September 13, 2010 4:56 PM
I chose to do research over attention,perception,& sensation disorders. The textbook did a good job at discribing how all three of these work together and help us function however, there wasn't very much information about disorders that are associated with these topics. This topic relates to the chapter because it discusses how certain people have disorders that affect their perception, attention, & senses and how the brain functions differ from a normal persons brain. I was really interested to learn more about different attention, perception, & senses disorders because those of us who do not have a disorder often times take for granted our senses, perceptions, and attention abilities & do not realize how much we use these three ideas on a daily basis.
The first research I gathered was about a visual perception experiment. This article discribed research that was conducted on normal people brains versus people with Williams syndrome. For those of us who are not familiar with Williams syndrome, it is a rare genetic disorder that affects development. Symptoms of this disorder include: delayed speech, easily distracted, feeding problems (reflux, vomiting), mild to moderate mental retardation, and learning disorders. The study wanted to find how people with Williams disorder perceived visual illusions and if their perception was different from that of a normal human. The experiement showed several visual illusional cards to groups of normal people ranging from 3yrs-adults. The same cards were used for people will Williams disorder ranging from ages 10-41 with avg age of 19. The study revealed that both groups tested the exact same way. The visual brain worked the same way in both the normal group and Williams disorder group. This experiment proved differently from previous studies which suggested Williams disorder were to spaitially imparied to have normal visual perception. Within the text it was said that perception is a way of organizing and interpreting sensory information which is exactly what happened in the experiment. There are different ways in which we organize our perceptions however this study showed us that normal brains and brains of Williams disorder patients organize that same way and their perceptions are similar.
The next research I did focused on the disorder of selective attention. Within the text I read that attention is the means by which we actively process a liminted amount of information from the enormous amount of information available through our senses, stored memories, and other cognitive processes. People who suffer from selective attention have a tendency to orient themselves toward, or process information from only one part of the environment with the exclusion of other parts. This article suggests that we all have a limited amount of memory to perform certain tasks (attention). These tasks are tasks that we are familiar with that have been stored in long term memory. With selective attention disorder, people have a harder time performing the tasks that they are familiar with & their brain does not function properaly to allow them to focus or perform certain tasks. My text briefly discusses how our attention processes allow us to give a 'heightened' focus to stimuli that interest us which in turn allows us to respond speedily and accurately. Selective attention disorder on the other hand on highlights a certain area of information and shuts out the rest of the environment which becomes very difficult for people to focus, perform accuartley and speedily with various tasks.
The last topic I research was the sensation disorders of taste and smell. This website really helped me understand the difficulties people face when they are unable to taste food or smell anything! This was my favorite topic to research because our senses are so useful and important to us. The website discribed that the sense of smell can be lost for a vairous reasons however the bottom line is once the sense of smell is lost, the sense of taste is lost too. One of the main effects from the loss of sense of smell/taste is a disinterest in socialization and eating which causes a serious nutritional deficiency. Within the chapter I read in the text it briefly describes that the sense of smell is also responsible for 3/4 of our flavor processes. This in turn describes how losing the sense of smell will eventually lead everything losing its sense of taste.
Overall, I really enjoyed this chapter about attention, perception, and sensation. Doing further research about disorders and their effects they have on these three topics really put into perspective of the important role attention, perception, and sensation play in my daily life.
http://www.wsf.org/family/news/hopewell.htm
http://www.csun.edu/~vcpsy00h/students/arousal.htm
http://www.tnicincinnati.com/sensestaste.html
While reading the chapter in my textbook on perception and attention, I found I was most interested in the section on selective attention. The textbook defines attention as “the concentration of mental effort on sensory or mental events” (MacLin, MacLin, Solso). There is an indefinite number of stimuli around us at every second and our capacity to sift through all of the information presented to us is very limited. Thus, our brains selectively chose to pay attention to some of these stimuli while ignoring the rest. The textbook does a great job of describing this as a flashlight being shown in a dark room. Only the things illuminated by the light are what get processed by the brain.
Attention is even more limited when two stimuli are trying to be processed at once. Maybe this is why parents scold their children for studying with music or the television on. This concept directed my interest to another topic discussed in other classes of mine: inattentional blindness. Inattentional blindness occurs when messages from a certain stimuli are lost because of competing messages from another stimulus an individual is paying attention to. I found two video clips that illustrate this concept very well. I would discuss the specifics of what is going on in each, but do not want to ruin the point of the videos. (http://www.youtube.com/watch?v=hDLLf_WCyZ4 ; http://www.youtube.com/watch?v=vJG698U2Mvo)
There are multiple explanations of why this blindness can occur. The first, I have already touched on briefly, is who our brain processes information. Our senses take in much more messages from our surroundings than our brain can process, therefore, the brain selects only a small number of messages to focus on and discards the rest. This whole selection happens even before the thoughts reach our consciousness. (This very brief video gives a good visual image of how this process works http://www.youtube.com/watch?v=3qkzzDyaJ2w)
One of the first factors that influence what we will notice depends on how obvious it is to our senses, specifically, the physical properties of the stimulus or the relevance of what is going on. This relates to a term in the textbook called the “cocktail party effect.” This basically means that amongst all the noise and crowdedness of a party, someone’s attention can be diverted just by the mention of their name from across the room.
Another reason for inattentional blindness can be determined by how much a person has to focus on at one point in time. This relates a lot to the video clips listed above. Practiced behavior can also fall victim to inattentional blindness. Tasks that have been repeated routinely a number of times by the individual may receive less attention.
Not much can be done to overcome the loss of information that accompanies inattentional blindness and selective attention because it is an unconscious reaction of our brain’s ability to adjust to the millions of stimuli our senses take in. The only advice that can be given is to minimize competing tasks that would hinder our performance on other complex tasks.
http://www.ismp.org/newsletters/acutecare/articles/20090226.asp
http://www.skepdic.com/inattentionalblindness.html
After reading the chapter in my text that covered perception, I became curious about what is known as pattern recognition. For me it is simple to perceive an object whether or not it is presented to me in several different ways, but just like anything brain related it is possible to have difficulty to recognize patterns. As defined in my text, pattern recognition refers to the step between the transduction and perception of a stimulus in the environment and its categorization as a meaningful object (Kellogg, 2003). An example of pattern recognition could be different views of a cat, but understanding that each view is still a cat proves that pattern recognition is working correctly. In this example there may be a frontal view of a cat, a side view of a cat, a rear side view of a cat, and a top view of a cat. Successful pattern recognition tells your brain that each view is of a cat. The perception of a cat begins with past information that has been stored in one’s memory of the basic themes that represent what a cat looks like. Your brain takes memory and patterns and combines them to perceive pattern recognition.
There are several pattern recognition tests online that can determine how well your brain can recognize patterns. These types of tests are created for humans. What is really interesting to look at is how scientists are applying visual pattern recognition (VPR) into computers and machines. VPR allows robotic machines as well as computers to open up into a whole other realm. With VPR machines are able to navigate on their own, recognize patterns, and allow for human to robot interaction. Products and programs such as visual search engines, navigation systems for vacuum cleaners, and security systems for retail stores are just some things that are taking advantage of VPR. In a way VPR works like the human brain. It begins to store basic patterns into its database which works like the human capacity for memory. Once the basic patterns are stored pattern recognition is based on pulling information from the computer database. Personally, I believe it is amazing how technology is advancing so quickly. I am already aware of search engines like Google that are trying to install the latest technology to help people search specific topics. I noticed now that not only can Google have an idea of what you are looking for before you type the entire topic in, but it also searches images that match this topic and these images will immediately visibly appear.
There are people who are able to determine an object based on its properties but cannot recognize it as a meaningful object. This problem is known as agnosia and is a neuropsychological condition. One example I found on Youtube was especially interesting. The man suffers from object agnosia and is shown a picture of a combination lock. He immediately feels this picture makes his hands want to move in a way that would unlock a combination lock, but he is still not sure that the picture is of a lock. It takes time to talk him through it and help him to understand what the picture is of. What is interesting to me is how his memory told his hands to move as if unlocking a lock, but yet his brain could not recognize patterns that told him he was looking at a picture of a lock. Agnosia is a frustrating condition and I’m sure it makes it very difficult to learn. My question would be if someone suffers from agnosia do they have issues with facial recognition or is the recognition of faces occur from a separate part of the brain?
http://ginasiomental.com/iq_tests/Pattern%20Recognition%20Aptitude%20Test.htm
http://www.evolution.com/core/ViPR/
http://www.youtube.com/watch?v=rwQpaHQ0hYw&feature=related
I decided to focus on the feature integration theory for this one. This theory proposes that object perception occurs in a sequence of stages in which features are first analyzed and then combined to result in perception of an object. This theory was developed by Anne Treisman and Garry Gelade and is probably the most influential "psychological models of human visual attention". It is pretty obvious that this theory applies to perception given the fact that the perception process is what it describes. This theory was interesting to me because it was interesting to think of perception as a process when perception seems to happen without effort, in the blink of an eye. The theory makes sense and helps explain how we percieve things, and considering it is so important to the study of perception this is why I chose it.
I have defined what FIT is, but I have not fully explained it. There are two stages to this process, the first being the preattentive stage. In the preattentive stage an object is analyzed into it's basic features, and happens automatically without the percievers knowledge. This basically means that when we look at something we percieve the objects by it's basic features (ie. shape, color, ect).
The second stage of this process is the focused attention stage. After we have processed the different features of an object, we can put these pieces together. In this stage the pieces are placed together and create the object that we see in front of us. Attention is very important in this stage, because the combining of the different elements is based on what the person thought they percieved.
In the text and two of my sites there is a reference to an experiment. While both of these experiements were done by different people, they are similar in method. In Teisman and H. Schmidt's experiment they displayed four objects flanked by two black numbers for about one-fifth of a second. After this they asked the participants what numbers they saw and then what they thought the four objects were. About 20% of of the trials the participants reported seeing objects that were somewhat blended with other objects. For instance, a blue circle and green triangle would be shown, but they would see a green circle. These results were reported to be because of a seperation of features of objects at the beginning of the perceptual process. The shape and color were seen differently and not necessarily as a single object, suggesting that these features are free floating.
The second experiment (url) performed a slightly different task, but had outcomes that also supported the fit theory. In the Chan and Hayward study participants were flashed a picture with a bunch of objects that looked the same, except for one. The one object was either colored differently or had a different tilt compared to any of the others. The participants were to report at first if there was one in the picture, but in the second part they were to indicate exactly where it had been (left or right side). The participants were able to indicate that there had been one in the field, but not where the object had been. This matches the results of the study above based on the fact that the lower level of perception could be processed, but not one of a higher status.
Another way to support this theory has been carried out in yet another experiement. There is a syndrome called Balint's syndrome which makes the person with the syndrome incapable of focusing attention on individual objects. With this defecit it would be very difficult to combine features of an object. A person with Balint's syndrome was given a task where they were presented with two different letters of different colors (like a green R and a blue H). He reported a good percentage of the time a Blue R and a Green H, even when presented the letters for 10 seconds.
With this theory in mind and the idea of preattentive focusing, Treisman also proposed that we have different maps in which we register a visual feature. This would mean that we have different maps that register when we see a certian shape or color, ect. This does not mean, however, that we can remember where a specific feature was in our visual field (this ties back to the second experiement). The importance of this can explain why it is easier to find a long line amoung a bunch of short lines.. but becomes more difficult as the long line gets shorter and closer to the length of the other lines.
FIT, like I said at the beginning, is a very interesting and influential theory to the field of perception. It explains our visual processing in very basic terms, and seems to have a solid standing on the research side. It is interesting to think of an objects feature floating randomly in mid-air, but this is what our brain does if it does not have enough time to fully process the object.
Urls:
http://viscog.hku.hk/users/will/Site/Publications_files/ChanHayward09.pdf
http://www.csc.ncsu.edu/faculty/healey/PP/index.html
http://www.absoluteastronomy.com/topics/Feature_integration_theory
One thing attracted my attention while I was reading the text. Although visual perception is pretty much physical and automatic process, it is also influenced by the external factors.
Visual perception system operates in through different processes in parallel. For example, as it is stated in the text, information from different depth cues is combined, but apparently more weight is attached to some cues than the others. Such process should be seen as the advantageous, as finally it makes the information synthesized from several sources rather than the only one more reliable.
Using this multidimensional approach we can construct the reality, not directly acquire it. During the construction external factors such as motivational and emotional states interfere as well.
One of the web links I would like to share is a blog, where several studies are presented and observed. In one of them the participants - kids from high and low income families – were asked to estimate the size of a coin. According to the results poor kids tended to see the coins bigger, than the kids from rich families. This might be an example of basic values influence on visual perception. Critique and explanations are also presented on the site.
If our perception is influenced by emotions, can we actually use it in order to cause some emotional responses? I thought about examples of using visual illusions in art. Probably one of the most famous “art illusionists” was Salvador Dali. I failed to find a good English language site that would represent his masterpieces with visual illusions, so I add the link for Russian website. You do not have to read anything, just to look at the pictures. I find it interesting, the way Dali plays with the viewer, puzzling him or her, bringing additional meaning to the painting. I do believe that this technique brought him and surrealism deserved fame.
It is important to notice that not only temporal emotional state influences our perception. In the research described in the first link it was family experience, economical background. But whole culture plays a big role as well. In the third link you can find the article about the difference in visual perception in Western and non-Western cultures. These differences have the same origins as various life experiences, social and economic background and are not “racial” to any extend.
These are basically my findings on visual perception and external factors influence.
http://scienceblogs.com/mixingmemory/2006/10/motivated_seeing_motivation_af.php
http://trinixy.ru/47073-opticheskie-illyuzii-v-rabotax-salvador-dali-18.html http://web.mit.edu/allanmc/www/socialperception14.pdf
“Cognitive Psychology. A Student’s Handbook”. Michael W. Eysenck, Mark T. Keane
As I was reading the chapter about sensation and perception I came across the topic of illusions and how the mind actually distorts reality. This is something that has always interested me. In many different psychology classes we have all seen cases where the lines are really the same size, but they do not appear to be that way. This intrigued me to do further research.
Something to learn is what you see or what you “think” you see may not always be reality. The perfect example of this is optical illusions. It is not your eyes that are playing tricks on you; it really is your brain. Due to the fact that visual areas are in the brain, it really has a lot more to do with your perceptions rather than your eyes themselves. The topic of illusions and “optical illusions” is what I chose to do and it is related to the textbook because of perception and how the brain deals with perception. The textbook states that visual perceptions typically occur in the occipital cortex part of the brain. Scientists have been using behavioral data, imaging technology (like what we have been talking about lately), and reaction time experiments to learn about cognition, perception, and sensations lately.
More specifically with illusions, one type of research is using the measurements of physical and psychological quality of the same sensory stimuli. Some reasons for why we interpret illusions wrong are due to past experiences or that the illusion reflects deep-seated invariant structures of the brain. Cognitive psychologists are studying illusions to try to understand how external physical phenomena and how the mind organizes stimuli in “internal representations” are related. Below are several illusions listed that were I found upon my research along with a little information about each one.
I wanted to know why the brain seemed to almost play tricks on a person and why we were so susceptible to optical illusions. The first illusion that was looked at was the spiral that usually appears to be "moving." It turns out that the reason your brain perceives the spiral as moving is because in the visual nervous system in the brain there are certain cells that respond to specific directions. The example was used that if a person was looking at a waterfall, a person would be using their downward receptors. If these are used for a long time they may become overworked and the next stationary thing you look at may appear to be going in the opposite direction (in this case the stationary object would appear to be moving upwards because the downward receptors were exhausted). This is known as the afteraffect.
Another example of an illusion we have all seen in class is where it appears a face is upside down, but while the whole face is upside down the eyes and mouth are actually rightside up. This causes us to instantly recognize a face when it is upside down; however, if we then flip the picture so it is rightside up (and the eyes and mouth are upside down) the face becomes unrecognizable. This is due to the fact that our brain will only recognize a face when they are rightside up. If it is presented as upside down then the brain will typically think it is an object. Another form example is the Necter Cube, where the brain flips between two different perceptions of the cube. Another one in relation to this that I had never seen before was of a face that was convex and concave, depending on which aspect you were looking at. However, once the face on the concave part came around the brain flipped it so seemed as if it was a convex object again. The reason for this is because the brain recognizes it as a face so will make the assumption that the face is convex.
There are other illusions, like for example illusory contours, where the physical object is not present, but the mind still seems to connect the dots for us. Again there are different reasons for these perceptions (evolutionary, theory to see “simple” figures). From another article I learned about the future study of illusions and how it is related to neuroscience. From this I learned that so far illusions have helped neuroscience (article gives a timeline of influence) and that some technology now will not really help to evaluate the brain as much as we would like it to. For example an EEG would “lack good spatial resolution” and an fMRI would have “too coarse of a temporal resolution to address certain classes of illusion.” There is a lot more research that can be done with illusions and neuroscience.
Another thing I found at the end was just the video (last link), it was just more illusions, but I really liked it.
http://www.pbs.org/wnet/brain/illusions/index.htmlv
http://cnl.salk.edu/~eagleman/papers/Eagleman.NatureRevNeuro.Illusions.pdf
http://abcnews.go.com/Health/EyeHealth/optical-illusions-eye-brain-agree/story?id=8455573
http://www.5min.com/Video/How-the-brain-works-Illusions-26618138
I chose two similar/related topics to do further research on. I looked at selective attention and divided attention. Selective attention is when we do not take in all the stimulus of our environment - we only take information that is important to us. Divided attention is when we taking in multiple stimuli from our environment, in other words multitasking.
These attention processes are enhanced when people have certain learning disabilities. For example with selective attention ADHD will show a ‘more’ selective attention than others. Because they have a shortened/lessoned attention span to start with. On the other end of the spectrum we have people who can not separate out important information from unimportant information - they have divided attention. A disorder that has this issue is Autism. They are unable to select certain information and therefore, get over stimulated easily.
This summer I worked with child with autism. Divided attention was very obvious - for some more than others. There were certain children that would plug their ears when things got too noisy. Or they would become loud themselves when things were getting hectic. Meal time was always a bit hectic because there were four kids with autism at one table. As well as two staff members that were trying to ‘direct traffic’. Add to the equation kids that stole food, kids that used too much ketchup, kids that spilled drinks (on purpose and by accident) you can see how it would be easy to get over stimulated. It was a lot to take in sometimes. There were some children who were constantly making noises (mostly the non-verbal kids) some kids obsessed over TV and movies. Some kids never stopped talking while others would act out movies… Not being able to discount some of this information would make for VERY divided attention.
There is very interesting research being done on divided attention or multitasking. With all the stimulus that kids receive today - how much are we learning? Research has shown that people who tend to multitask actually do worse on multitasks than people who prefer to focus on one task at a time. When in class a student can be multitasking with several things (face book, texting, taking notes, talking to a friend, doing homework for another class, studying for a test later that day etc.). Nass states that even though these people are doing many things - they are alert and can here the teacher; they are taking notes, they are not learning as much as they think they are. They are accomplishing a lot but they are getting less out of each task - had they been doing one thing at a time.
Now that I know what selective attention and divided attention are I wonder what category people, like Bennett, with tourettes would fall in? Does Bennett have over selective attention to things like where his glasses sit on his face, where his knees are compared to the alignment of the steering wheel, and whose attention he has? Does his brain consciously chose to focus here? Or is it something that is unconscious like answering a known voice compared to an unknown voice when both say your name at the same time.
Or does Bennett have qualities similar to those with autism? Where he can not focus on the task presented unless other stimulus are fulfilled first - until he has completed all of his tics. I do not think this is the case. I think Bennett has very selective attention - however, it takes a lot of focus to keep his attention. In the AM reading Bennett told Sacks that he would read and reread his medical books, each line repeatedly. This single task held his attention until he could move on. As Nass suggested people who focus on one thing at a time actually take more away from their task. Maybe this is why Bennett is a successful surgeon. When performing a task, such as surgery, Bennett can get through it without any compulsions or tics as long as his rhythm is not broken/ as long as his focus is not interrupted.
These are very interesting topics. I have been thinking of them as two separate processes - like people do not possess both. I think people do possess both. It is a matter of which process they use more. Right now I am listening to music, typing this blog, checking email, face book, and doing research online. Yet, I think I am totally focused… This divergence task has given me lots to think about - and there are many other areas where this research will be applicable.
http://chronicle.com/article/Scholars-Turn-Their-Attention/63746/
http://www.wisegeek.com/what-is-selective-attention.htm
http://arstechnica.com/science/news/2009/08/multitaskers-beware-your-divided-attention-comes-at-a-price.ars
Web Divergence Activity----Week #3
Our memories of objects play a huge role in our Sensations and Perceptions and also what we devote attention to. I decided to focus in on a particular part of our memory systems. The Semantic Memory system can be described as an area of our long-term memory that consists of knowledge about the world around us. Our knowledge of living things is stored in one part of the brain and memory whereas non-living things are stored in another part of the memory and brain. “There may be non-overlapping areas of the brain that are important for processing different categories of items. The inferior areas of the temporal lobe appear to be especially important for processing living things and the posterior area of the temporal lobe and frontal-parietal areas appear more important for processing non-living things.”
This applies to the topic of our Semantic Memory because it talks about the process of storing memories and how we retrieve those memories at a later time. The book talked about developing short term and long term memories and this information in the clip provides a lot of useful information regarding the memory system. I find this topic interesting because it is a very liter topic. Our memories are used every day of our lives and we don’t always realize what is happening. I find information like that very interesting and therefore want to learn more about it.
I watched a YouTube clip talking about how our memory systems work to store memories. One main point that the video stated was that we remember most things through associations. Our memories and sensations all begin as electrical impulses through the brain. As each sensation relates to one another tiny synaptic junctions form. This is how memories are formed within our brains. As each association occurs, our brains allow that memory to become stronger and stronger, so therefore we don’t forget it. So when we repeat something over and over in our heads and keep repeating that phrase, number, etc, we then remember it. The more that we repeat it we develop an associate with that repetition so then later on we can pull that out of our memory. I like the example that he used about how we remember the breakfast we ate this morning. It made perfect sense when you think about it literally. When we associate our senses with something, we remember it. For example, you don’t forget the taste of orange juice after your brush your teeth. We develop an associate with that taste so then we know from our memories that you don’t drink orange juice right after you brush your teeth. Another thing talked about that was cool was the idea that memories are more like a complex network of stored sensations rather than like a film strip that we pull from. Memories can deteriorate over time if this information is not used on a regular basis. This can be called “Use it, or Lose it.”
http://www.youtube.com/watch?v=grZuwo_YlY0&feature=related
My topic is called the cocktail party phenomenon. Before reading the chapter on perception and attention, I hadn't heard of this phenomenon before. The Cocktail Party Phenomenon, a model of selective attention, is basically one's ability to focus in on one conversation despite the presence of other conversations and/or background noises. This topic fits in with the chapter because it explains a necessary human attribute that is responsible for letting us process a reasonable amount of information without overloading our neural capacity.
The Cocktail Party Phenomenon came to light back in the 1950's when research on the term 'shadowing' was done by a man named Colin Cherry. Shadowing consisted of subjects repeating a spoken message that they have been presented with. The main part of Cherry's research involved two messages being given simultaneously to the subject. Subjects remembered a only a little of the initial shadowed message and even less of the unattended message. When subjects were presented with audio messages in both ears, they were able to decipher the messages much easier. The ear with the message instructed to be rejected proved to have interesting results. Subjects were unable to identify certain phrases or words despite their repeated presence. The rejected ear also failed to recognize changes in the language being spoken. The auditory system, however, still has the ability to identify a specific signal in a mixture of sounds. Research done by Broadbent in the late 1950's suggested our brains interpret sounds based on physical characteristics. These interpretations allow us to select which sounds are important without overloading our working memory. In 1960, Treisman's research found evidence that important information like a name embedded in the unattended message increases the likelihood its perceived by the brain.
Recent research has shown the secondary auditory cortex, located in the temporal lobe, may be responsible for deciphering between multiple sounds. In a study done by Alexander Gutschalk, researchers found a surge of activity in this portion of the brain when the subject was directed to identify the regular tones in a string of random ones. Despite all the information on selective attention, researchers still do studies relating to the cocktail party phenomenon, showing us that there are still a lot of different variables that might affect how humans perceive sounds and interpret them.
http://www.spring.org.uk/2009/03/the-cocktail-party-effect.php
http://pbr.psychonomic-journals.org/content/8/2/331.long
http://www.newscientist.com/article/dn14096-party-chat-brain-filter-discovered.html
I chose selective attention because a large part of the chapter in my book talked about how we receive a whole lot of stimulation from the environment but then remember only a little part of it and pay attention to only a little part of it.
I have been told about selective attention before and I had been referred to a test of selective attention demonstrating its effects. I tried it on a friend. The link is included below and the video is on youtube, however it probably will not work on anyone because I am about to describe it. What happens is, there are three black T-shirted and three white T-shirted people and the black T-shirted people pass a basket ball among themselves and so do the white T-shirted people. The viewer is told to count how many times the white T-shirted people pass the ball. And they pass the ball about fifteen times. But halfway through the video a mascot-like gorilla enters the scene and does a funny dance. This is very distracting to a normal viewer, but my friend did not even notice the gorilla. If a person is as focused on the basket ball as my friend was, then they would not have noticed it either.
There are three different major researchers on selective attention. They are Broadbent, Treisman and the Deutschs. All three have different theories on how selective attention works but their main argument is over when and to what extent selective attention occurs.
Broadbent thought that it occurs directly before any processing of sensory input happens and is complete. Once it happens, all other input channels are ignored.
Treisman thought that selection happens after some level of processing occurs and the other channels are never completely ignored. They are attenuated. The main source of evidence for this comes from his shadowing experiments where he made the subject repeat everything he hears from one ear and not the other. He fed a story through the selected ear and had other noises on the other ear. Halfway through, he switched ears so that other noises came from the ear the subject was attending to (so the subject is suppose to make noises) and the story is fed to the unattended. However, the subject just continued on with the story. Therefore, perhaps it was not the source of the input that helps in selection but it was the meaning of the input, the input itself.
I have some issues with this experiment. I think that people enter into a mental set when they are put into situations like those. So the subject associated the story with the attending ear so a sort of classical conditioning is occurring here. So finally the ear is not attended to but the story is. Maybe, if he had told the story either a word at a time or a sentence at a time, switching between ears, there might have been more powerful evidence. But that is just me.
The Deutschs actually propose that the selection happens at the point of response. Really, you process everything but you respond to only one or just a few of the things in your environment. So they propose that the selection process happens very late and is not quite as conclusive as Broadbent had thought.
http://www.google.com/url?sa=t&source=web&cd=9&ved=0CDkQFjAI&url=http%3A%2F%2Fwww.tamiu.edu%2F~jbrown%2Fdocuments%2Fcog3.ppt&rct=j&q=Treisman%20selective%20attention%20theory&ei=K9mQTOu9CIeVnAewoPG0DA&usg=AFQjCNHJk1hUGZz4XSuP5nJbaAOO71Uwnw&cad=rja
http://misc.thefullwiki.org/Broadbent%27s_filter_theory_of_selective_attention_and_short_term_memory
http://www.alleydog.com/cognotes/attention.html
http://www.csun.edu/~vcpsy00h/students/arousal.htm
http://www.youtube.com/watch?v=vJG698U2Mvo
Sorry for the late post..trying to keep up.
Facial recognition is a complex processing system and is essential for our social interactions, and our brain is able to do it almost instantly. An area in our brain called the fusiform gyrus is thought to be a major part of the facial recognition process, the fusiform face area (FFA) specifically. Recent research into this area suggests that the area may not be specifically to recognize faces, but may be used to find small distinctions between similar looking objects.
The social implications of facial recognition are greater maybe than any process other than speech. We communicate our own state of mood and are able to decipher others' emotional state all with the small changes we make in our face. Perhaps why such a relatively large area of the brain is dedicated to the fine motor control of the face. A study published in the journal Neuropsychologia in 1999 found that subjects with bilateral amygdala damage had significantly lower abilities to recognize fear and some other negative emotions in faces. Although there was not a significant difference between those with amygdala damage and the controls on recognition of positive emotion, the results of this study may provide a piece of the puzzle of face recognition. Perhaps the amygdala is the area in the brain that is activated to identify negative emotions, particularly those based on fear. This is interesting because the amygdala is also linked to producing a sense of instinctual fear. When we are startled and jump or yell, it is because as information is processed through the amygdala, surprising or scary stimuli trigger some reaction and the amygdala sends the message "RUN" to our conscious mind. Perhaps all emotional recognition is based in the same areas that produce that emotion.
An article on a website called WorldScience.net discussed a study in which a Montreal PhD student investigated what areas in the face provide the cues for us to read emotion. The participants were shown several faces and asked questions regarding their emotional state and whether the face was recognized. Eye-tracking was used to see where exactly on the face the participants were focusing. She found that in her sample of caucasian Canadian participants the eyes and mouth seemed to be the center of attention and for her sample of Asian participants the nose seemed to be the focus. The study also indicated that Asian participants often confused negative emotions, perhaps because they do not focus on the mouth when reading emotion.
Why does this difference exist? The author of the study suggests culture or biological effects are responsible. If culture determines how we interact with people by influencing how we recognizing emotion then does it also affect how we portray emotion. Do Asian people not use their mouth as deliberately as other parts of their face when making facial expressions.
Facial recognition is thought by many to be just a complex type of pattern recognition, but the information provided by our processing of faces is so great that I believe it must be a series of complex processes to yield such a complete perception of someone so quickly. When we see a face, we know instantly that it is a face, whether we know the person, roughly how the person seems to be feeling, and whether they see and recognize us. This happens pretty much instantly and holds so much social value that it is unbelievable. We can all recognize George Clooney and our own mother, and we can all tell what a smile means. Facial processing is a key trait for humans and it obvious that sight is the main sensation that gives us information about the face, but the area most correlated to facial recognition is the fusiform gyrus located on the temporal lobe, not the occipital lobe like you would think. This leads me to believe that our facial processing ability is derived from the synthesis of several different systems acting together to decipher all the information provided by a single face.
Sources
http://www.world-science.net/othernews/100126_faces.htm
http://en.wikipedia.org/wiki/Fusiform_face_area
http://www.cs.phs.uoa.gr/el/courses/emotions/papers/ADOPLHS%201999.pdf
After reading this chapter I choose, for this blog, to learn more about illusions. There was a section in this chapter that talked about illusions and I wanted to learn more. Why do these illusions happen? While I looked around the web for information I found the most cool and unusual things! Sometimes I would have to stop looking for awhile because the illusions would make my stomach a little queasy.
There is a lot of information regarding illusions and the brain, a lot depending on the type of illusion. But there is also a lot that is still not known about illusions. Illusions fit best in the field called psychophysics. Studying illusions, while fun, can also tell us a lot about the normal and abnormal brain. They can also give us an idea on how the brain processes work.
There are different types of illusions and different reasons why the brain acts the way it does. Sometimes the brain is working based on past experience, and related, sometimes the brain tries to predict what will happen next (which turns out to be wrong in the case of illusions). This happens by your brain trying to create a shortcut. After it receives the first data it tries to guess at the next image before that information reaches it. There are many illusions that focus on the human face and we can even see the moment we (our brains) recognize faces as faces in one illusion. The fact that the brain recognizes such things as faces and shapes is often exploited in these illusions. There are numerous different illusions that you can see different images (i.e. vase or profile of two faces, duck or rabbit, etc), but you can only see one at a time, you often can only see the other if someone directs you too, and you have to have experience or knowledge of the objects in the image. Different distances can also play a part in illusions. Another type of illusion deals with luminance changes. The lightness/darkness changes which gives the illusion of the image moving, suggests that the brain see changes in light as motion. In watching some motion illusions (such as the spiral) that part of sight may tire and then the opposite may over compensate or overreact. In other illusions you can put filters over one eye making the input from that eye take longer to get to the brain because it waits longer to collect more light and therefore by the time it reaches the brain its old news compared to the information from the other eye, this can create an illusion. Different colors amongst colors; different lighting (wavelengths) are responsible for our rich variety of colors. Another thing to keep mind is that the eyes look at things from different angles and this helps with calculating depth.
Perception can be influenced by past experience, ideas, prejudices, and sensory signals. Locations in the brain (V1 and V5), towards the back, is related to the perception of sight. We see by learning how to see. We see the way we do because it helped us in the past. Some illusions have you look at color(s) and then at a different scene which then has at least a tint of the color(s) you were looking at before. This is because your brain got use to it and it became the new norm. Some illusions have you look at a rotating image that can often change direction. Without some cue, rotating either way is just as likely so the brain can see both, but not at the same time. Your brain decides what to deliver to consciousness, regardless of what you know is real. What we see is only a best guess by our brain.
http://www.youtube.com/watch?v=9CEr2GfGilw
http://www.youtube.com/watch?v=mf5otGNbkuc
http://abcnews.go.com/Health/EyeHealth/optical-illusions-eye-brain-agree/story?id=8455573&page=2
http://www.pbs.org/wnet/brain/illusions/index.html
http://www.youtube.com/watch?v=zHB-1kH91Ts
http://www.youtube.com/watch?v=uWd9Ka0hkgQ
http://www.youtube.com/watch?v=zSpdetR69Oo
http://www.youtube.com/watch?v=eodP1rsINek
http://www.youtube.com/watch?v=8Oi9Kp7qBUk
http://www.youtube.com/watch?v=SFN-3OUTCYk
http://www.youtube.com/watch?v=q5VAfFByXQo
In my cognitive psychology book, there was a subsection about the way we view some two-dimensional surfaces as three-dimensional. Any picture or piece of realistic art work gets translated into the brain as three-dimensional. Artists use different tricks to accomplish this, such as a vanishing point, relative size, color shading and others to create the illusion of depth on a two dimensional surface. Photos use the same thing, only cameras capture the image as “is” rather than the photographer creating the image out of nothing.
When you actually stop to think about the way a two-dimensional picture is perceived as three- dimensional, it actually is pretty amazing. We look at a two-dimensional surface and due to “tricks” of the brain to see three-dimensional images. It has to due with a human being's amazing ability of abstract thought. When looking at the three-dimensional world, we on a unconscious level are aware of seeing highlights and shadows. We transfer this to two-dimensional surfaces; a lighter or darker color represents the highlights and shadows of the three-dimensional world. The same goes with other tricks artists use. Unless you have studied art, one is not fully aware of relative size or vanishing point in everyday perception of sight. When one sees it on a two-dimensional surface, our brain translates the visual cues into a three-dimensional surface. Our brains translate relatively random blots (or dots in the case of photos) into a three-dimensional surface based on our visual perceptions of the three-dimensional world around us. Even a simple use of lines can be perceived as a three-dimensional shape, such as cartoons or even a simple “cube.”
Lines are instrumental to our perception of two-dimensional objects. It has been hypothesized that lines give us a border from which to define an object. The earliest prehistoric art was made of almost purely line. It suggests that our abstraction of sight is based on defining our perceptions. Two-dimensional pictures are static, unlike the three-dimensional wold around us. It is far easier to focus our attention and perception on the objects created on a two-dimensional surface.
Photos are especially amazing. Even if one has never seen the picture before, one recognizes actual objects on a two dimensional surface. Digital photographs basically recognizes certain light waves (colors), records it in dots known as “pixels”, and transfer it to paper or a screen. Photos are nothing more than tiny dots of color, yet we recognize objects even if that is not how our eyes actually process our visual field. Our brains take up “cues” and transfers it into something definable. We can recognize a person on Facebook even if we have never seen them make that face before, or despite the fact that it is nothing but dots of color. Our brain processes the “shape” of the face; the eyes, nose, mouth, jaw, etc. based on shadow and light that translates into line, then as an object, then as the brain searches its memory bank comes up with a familiar object (in this case a person), we perceive it and recognize the two-dimensional surface as an abstraction of a three-dimensional object we have seen before. Even a picture of a place or a person we have never seen, we recognize it as what it is; a building, a savanna, a jungle, etc. It is not so much that two-dimensional pictures deceive our brain, but that our brain it able to create abstractions of what we see and remember it.
http://dspace.mit.edu/bitstream/handle/1721.1/5957/AIM-1366.pdf?sequence=2
http://www.macalester.edu/psychology/whathap/ubnrp/aesthetics/perception.html
http://www.aber.ac.uk/media/Modules/MC10220/visper05.html
One of the more interesting things I came across while reading the text was about prosopagnosia, or the inabiblity to recognize faces. The text discusses holistic processing in which we percieve a whole object at once. During normal facial recognition this explains how we process a face as a whole instead of using analtic processing where we percieve the parts that make the whole. Persons who sufffer from prosopagnosia may have abnormalities, damages, or impairment in the right fusiform gyrus. It would seem that this small area contributes to the ability to recognize faces. The strangest part of this condition is that it only impairs facial recognition and seems to have no effect on other forms of object recognition. There are varying degrees of impairment where some people may have difficulty recognizing unfamiliar faces until they have been exposed to them many times and others cannot recognize spouses, children, and even their own faces. I got even more excited when I came across Oliver Sacks new book in which he discusses his own struggle with being a prosopagnostic. The book was already on my "wanna read it" list and now I am really looking forward to it. Another interesting piece to the puzzle is the possibility of a link to children with Ausperger's syndrome or other autism spectrum disorders. There is still alot of research being done to find those who appear to have a genetic link to prosopagnosia. It can be difficult to tell if someone has a problem with facial recognition because it is one of those things that we take for granted and dont discuss. Those who have prosopagnosia tend to rely on other cues to recognize people around them, so it may not be obvious to others that there is a deficit. Those who suffer trauma or stroke later in life who have already developed facial recognition abilities would be aware of a change, and are therefore easier to identify. There is still alot of research being done, expecially to the group considered to have genetic prosopagnosia. I look forward to following the research and seeing what develops.
http://www.faceblind.org/research/
http://www.ninds.nih.gov/disorders/prosopagnosia/prosopagnosia.htm
http://www.cbsnews.com/8301-504763_162-20014826-10391704.html