Think of the material we have covered so far in class. Next find a topic related to your interest 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
Include a list of the terms and concepts you used in your post. (example - Terms: memory, cortex, visual system....)
Let me know if you have any questions.
Topic: Selective Attention
Studies in selective attention have always been fascinating for me to study, therefore, I decided to expand upon the small section from our book regarding the issue and explore some other reports and videos surrounding the topic.
The textbook utilizes the "bottleneck" idea regarding selective attention which theorizes that somewhere during the processing of information, all of our sensory inputs encounter a narrower, or selective area of input that then determines what we focus on. This theory was the initial theory regarding selective attention. While this theory is strongly supported, I found it interesting that others have discussed whether we simply dismiss the "other" sensory inputs that we are not attending to or if we unconsciously store them away for later use.
Regardless of which theory is accurate or more prevalent, the issue of arousal is undeniable. What we will focus our primary attention on is certainly going to be whatever has aroused our interest the most. If we are instructed what to focus our attention on, we may miss something quite abstract, unique, blatant, or otherwise stimulating to the casual observer. Note the video from my second link. An incredibly abnormal occurence is dismissed by most viewers until it is mentioned and then replayed. Once you view it a second time when you have been instructed what to look for, you will certainly see it.
There are also the capacity models that have been studied regarding this issue. The first research was done in the 1940's using the game of chess (Degroot). Plays of different abilities had five seconds to view the board during the middle of the game. All of the pieces were then removed and the players had to replace them. Higher ability players scored close to 90% while lower ability players scored close to 40%. This research certainly seemed to yield strong results for the capacity model.
Competing information is another factor that has been examined and replicated in numerous studies. Studies have been performed on animals as well regarding their selective attention on prey while they are moving. The more competing information there is, the more distracted we become and the less likely we are to be able to focus on the particular stimulus. This is not only true from a visual standpoint, but also from an auditory one as well.
Terms: Arousal, Bottleneck theory, Sensory Input, Capacity Model
http://www.csun.edu/~vcpsy00h/students/arousal.htm
http://www.customerinput.com/journal/do_the_test_selective_attention_and_advertising.asp
http://findarticles.com/p/articles/mi_hb6024/is_200909/ai_n42857072/?tag=rel.res1 (Numerous articles to look at)
Web Divergence Activity – Week #4
Topic: Cataract Surgery
Cataracts can be described as the clouding that develops in the crystalline lens of the eye or in its envelope, which can vary from the amount of light passing through the eye. Cataracts can occur when changes in the lens fibers change metabolically. This causes impairment or loss in a person’s vision. Cataracts may also occur when the water and protein in our eyes begin to clump together and clouding the lens. Some ophthalmologists believe that Cataracts are a product of growing old. They think that Cataracts o=being to occur naturally in the eye. Symptoms of Cataracts can include things such as cloudy, fuzzy, foggy, or filmy vision, double vision, trouble seeing at nighttime, sensitivity to glares, etc. Cataracts usually occur in one eye versus both eyes and the vision in that eye begins to decrease over time.
Cataract Surgeries have been around since 6th Century BCE. In those times this procedure was called “Couching” and was done quite differently. Then, a needle was curved and pushed through the lens and out of the field of vision. The eye was then soaked with warm “clarified” butter and then had a bandage put over it. This method was considered to be a success but it was thought to only occur if absolutely necessary. Today, the surgical procedure of Cataract surgery is quite modernized. Cataract surgery includes the removal of the lens of the eye, which can be referred to at the crystalline lens. After the lens is removed doctors then replace it with a synthetic lens to allow for the lens to work again.
There are 5 different types of Cataract surgeries that can be done which include, Extracapsular Cataract Extraction, Phacoemulsification (Phaco), Conventional Extracapsular Cataract Extraction (ECCE), Intracapsular cataract extraction (ICCE), and Cryoextraction; which is a type of ICCE performed.
Cataract Surgeries vary in range of costs as well. Having a private doctor perform this surgery will run you from anywhere from $2,000-$3,000 per eye. The waiting list to have this procedure done is quite long and there are some people that have had to wait up to ten years to have their surgery. Although, on average, a person will wait from twelve months to two years to have their cataract surgery done.
Terms : Cataract, Cataract Surgery, crystalline lens, envelope
https://health.google.com/health/ref/Cataract
http://www.youtube.com/watch?v=bqu0fJ0JY_U
After looking up information in the textbook on the chapter in AoM, I stumbled upon Gestalt Theory and wanted to read up on it some more. According to the textbook, Gestalt Theory is “pattern recognition based on the perception of the whole pattern of stimuli. Parts of the entire configuration derive their meaning from their membership in the whole” (pp. 108).
Research in this area was applied to visual perception by Max Wertheimer, Wolfgang Köhler, and Kurt Koffka. Köhler believed in “natural organization” which means that “spontaneous organization of a pattern was a natural function of the stimulus itself and only minimally related to past experience with the object” (pp. 113). These three men attempted to explain how parts of objects working together could go beyond the sum of the objects as a whole. Through their investigations led to principles of Gestalt Theory.
The first principle deals with similarity. This basically states that objects within the same structure are perceived together as a unit. The principle of proximity means that those objects placed together are seen as a grouping. Take for example, nine squares spread out from each other. These are each perceived as a separate squares, however, when placed together in a three-by-three figure, the nine squares suddenly become one larger square made up of smaller ones. Figure and ground captures the idea that in perceiving a visual field, some objects take a prominent role (the figures) while others recede into the background (the ground). For example, I am sure many have seen the rabbit/duck illusion. The closure principle explains that if a picture is almost nearly complete but not completely enclosed, the brain will fill in those gaps. Continuation is another principle in which a picture provides a perception of movement that leads the eye to another object.
This theory relates back to my post about bottom-up processing. With this theory, we perceive the smaller portions of an object to visually understand the object as a whole.
Terms: Gestalt Theory; pattern recognition; visual perception; natural organization; principles of: similarity, proximity, figure and ground, closure, continuation
Textbook: Solso, MacLin, MacLin. (2005). Cognitive Psychology, 7th ed.
http://graphicdesign.spokanefalls.edu/tutorials/process/gestaltprinciples/gestaltprinc.htm#continuation
http://www.interaction-design.org/encyclopedia/gestalt_principles_of_form_perception.html
http://www.thepsychfiles.com/2007/10/episode-31-lemon-slices-and-a-new-face-on-mars-gestalt-principles-at-work/ (for examples on each principle)
I decided to do further research on eye fixation and movement. This topic fits in the chapter because of the many new experiences that Virgil was going through. His sight was still very impaired and what he did see was difficult to process - or make any sense of. His eyes had lost their ability to ‘see’. He could not pick out what was important and he could not transfer images of the objects he saw into the objects that he touched. Virgil had to relearn to see even though he could see as a child he had been almost fifty years without sight. I also found this topic interesting because I recently met someone who was missing a muscle in his eye that did not allow it to settle on a single object. His eyes are in noticeable, constant movement. I chose this topic because I am interested in why his eyes did that and how much work Virgil, and others like him, would have to do to keep their sight.
There are two sets of muscles that control our eyes. There are internal muscles that work with focusing and pupil size. External muscles direct eyes and keep retinal in slight but constant movement. It was the external muscles that caught my attention. Is that what my friend was missing? We all have constant but slight eye movement but, we do not notice it. Why is his so noticeable? Is he missing the muscle that holds are eyes ‘more’ steady? Then I started thinking about Virgil. What were the muscles in his eyes like?
If a muscle is not used in forty sum years it would be pretty weak. That is why Virgil would get worn out after using his eyes for an extensive period of time. Like any muscle group, eye muscles get fatigued. There were two reasons for fatigue that I found very interesting and did not expect. The first was walking. When we are walking are eyes are constantly interpreting stimulus from our environment. While we move objects around us appear stationary - which they are. However, if you think about it our eyes are stationary to our head so when we walk past something it should appear that those objects are moving. Sighted people will have experience with this sort of visual processing. Virgil on the other hand would have a more difficult time with this new processing - remember before sight his world was not in space but in time (when objects, people, stimuli passed). He lives in a world of sequential stages - we use this as part of our information processing but it appears to be Virgil’s main way of processing. The second reason we get fatigued is when we make errors. Virgil was working to use his vision, then making errors, and then his brain would have to do extra work trying to correct those errors.
In class we have talked about the many ways to process information. Like, how we take information from our world - then how do we store and use that information. In my first blog for this chapter I talked about how we see things from a world we have built. Everyday we wake up with the knowledge and images that have experiences previously. For Virgil he is taking in a new world in a new way. He is processing information like an infant would but, with quite a disadvantage. His brain is not as plastic and the areas he used to use for sight have been put else where for compensation. In one of my articles it talked about eye fixation in infancy. It is important to build up focus with caretakers. Kids who watched more TV were found to make less eye contact later. I found that interesting - the variability in lifestyle among sighted people. Looking at a TV is not he same as looking at others’ faces.
In our notes it mentions eye tracking studies. Where do our eyes land? We use conceptually driven processes. We have memories and knowledge (unconscious and conscious) of what is important. We know what we need to look at, what visual input is necessary, to make a coherent - holistic object. Virgil did not have this knowledge. He probably had the ability as a child but lost it over nearly 50 years without using it. From what I have found vision and eye sight falls into the realm of ‘if you don’t use it, you lose it’.
Virgil, and people like him, did not know what to look for - nor did that know how to focus on something. They were bombarded with all of this visual stimuli too much to take in all at once. Fixation, in others words, was difficult for them. I found recent studies and articles about a new implant that people are using. They use it for people who have had cataracts removed from their eyes. At first I thought this may have helped Virgil - it would have made it easier for him to use his eyesight. However, I found that this implant had deflated in some cases. I am not sure of the exact mechanics of the object but it looked like an inflated spear that went through the eyeball. If this deflated then it would serve no purpose and could potentially damage the eye.
Other regenerative information included stem cells that were being used. For patients who had lost their eyesight due to chemical burns. It took time for their vision to return - which makes me think that the stem cells were put into the eye and then had to grow and mature into the necessary cells. This is interesting but I wonder why it is restricted to chemical burns? Is there more ways it is being applied? Could it work for people who have had cataracts removed?
There are many people who are struggling with their eyesight. Whether it be from wearing glasses to having your eyesight lost in an accident or due to illness. This research will help many people - eye fixation and movement is just a small function that are eyes perform.
Terms: holistic processing, conceptually driven processes, external muscles, internal muscles, eye tracking studies, sequential stages, processing information.
http://www.pc.ibm.com/ww/healthycomputing/vdt13eyeb.html http://www.ehow.com/facts_6919371_fixation-eye-movement-information.html
http://www.businessweek.com/news/2010-06-18/stem-cells-from-own-eyes-restore-vision-to-blind-update1-.html
Senses of the Blind
I had previously heard that blind people have more acute senses, in order to compensate for their lack of sight. I was curious to find out if this was true.
According to research blind people‘s sense of smelling, hearing and touching are not any better than those who are able to see. During studies blind people and people who aren’t blind scored relatively the same on the above senses test. It is assumed that blind people are simply more attuned to their senses and use them more effectively. For instance, while testing blind and sighted children’s sense of smell, the blind children were no better at distinguishing smells than the sighted children. However the blind children did use more labels for the different smells than the sighted children. The blind may be more attuned to there sensory processing.
The age at which the blind lost their sight does tend to make a difference when testing for sound. Those that lost their sight early in life, between the ages of birth and four or five years old did do better when testing for sound than children who could see. The exception is that if sight was lost after the age of 10, they were no better at hearing than the sighted. This may be because when we are younger, the neurons in our brain are more capable of redirecting themselves in order to compensate for the loss.
While researching the topic, I stumbled on some research about echolocation and just how beneficial it may be for the blind. Blind people use echolocation to locate and identify objects. Bats were the first creatures to use echolocation as well as dolphins. Bats use high pitch squeals that bounce off objects, like mosquitoes, which than sends images to the bats brain. The bats are than able to locate food and “see” when flying in pitch black. Like bats, the blind also make a sound with their mouths, which is referred to as a “palettel tongue click.” The sound bounces off objects as well as the air and allows them to locate objects and identify their surroundings. They use different “tongue click” pitches depending on their location. When they are inside the “click” may be a softer, quieter pitch as opposed to being outdoors when the click may be a high, loud pitch.
I watched a short video clip that demonstrates how blind people are able to ride bikes on the street and also on narrow bike trails using echolocation. Echolocation seems to be a very useful tool for the blind and the technique allows them to do everyday activities that sighted people are able to do. It is pretty amazing.
Another interesting finding in regards to the blind is the amount of activity in the visual processing areas of the brain. PET scans reveal that although the blind are not able to see, there is still activity in the visual cortex part of the brain when they are using other senses. Even though the optic nerve isn’t sending images to the visual cortex it appears that that part of the brain is actively involved.
http://www.youtube.com/watch?v=uobuBc2GO0o&feature=player_embedded#!
http://www.spring.org.uk/2008/02/blind-peoples-other-senses-not-more.php
http://health.msn.com/health-topics/articlepage.aspx?cp-documentid=100234436
Textbook: Solso, MacLin, MacLin. (2005). Cognitive Psychology, 7th ed.
Terms: visual cortex, PET, sensory processing
Topic: Apperceptive, Associative, and Mirror Agnosia
After reading about Virgil's case I was very interested in the agnosia disorder. Since I wrote about agnosia for the reading activity this week, I decided to do further research into the different types of agnosia. The types of agnosia that I learned more about are apperceptive, associative, and mirror. All of these relate to our readings because they are forms of visual perception disorders.
The apperceptive agnosia is described as a lack of high-level visual perception which makes it hard for indiviuals to gather object information. It is very common for people with this type of agnosia to fail tests such as visual matching, comparing similar figures, and copying drawings. For example, a patient with apperceptive agnoisa that is trying to copy a drawing of a circle will attempt this by drawing a series on scribbles and describing them as circles.
Associative agnosia patients are able to visually perceive objects presented to them and perform basic tasks however, they are not able to assign meaning to the objects or organize items into categories. Prosopagnosia is a subtype of associative agnosia.Patients with this agnosia are unable to recognize faces. Some cases are so severe that they are unable to recognize their own face. I researched a youtube clip in which a man suffered from Prosopagnosia. He was even unable to recognize the interviewers face when she stood next to another women. He even admitted that he might not be able to recognize his own wife's face if he saw a picture of her.
The last form of agnosia is called Mirror agnosia. This was very interested and new for me to learn about. Patients with this disorder are unable to differentiate between real and reflected items and mentally rotate objects. The interesting part of mirror agnosia is that these patients are usually aware of the 'mirror' yet they are still unable to correct their behavior. An example of mirror agnosia is a patient who has been show the real location of the object yet they still believe that the object is behind or in the mirror of itself and they reach for it accordingly.
Agnosia is a severe disorder and all three of these types of agnosia create great difficulties for the patients. Our visual perception is very important for us to not only see and visualize but also to process and perceive our environment, information, and even faces of friends and family.
URLS:
http://www.davidson.edu/academic/psychology/ramirezsite/neuroscience/psy324/lerossello/visual_agnosia.htm
http://www.healthline.com/galecontent/agnosia
http://www.youtube.com/watch?v=XLGXAiSpN00
Terms: Agnosia, Apperceptive agnosia, Associative agnosia, Mirror agnosia
For this post, I have chosen to discuss about split brains. It is such a fascinating, mind-boggling phenomenon and I wanted to know more about it. Certainly, it was something discussed in Introduction to Psychology and later in classes like Biological Psychology. Of course, we also discussed this in class, so I was skeptical about my choice and was worried that I would not be able to find much about it.
I was wrong. I was fortunate to stumble on summaries written by Sperry and Gazzaniga and they provided more detail than I imagined.
As already discussed in class, split brain research stems from the cutting of the corpus callossum. This effectively separates the two hemispheres of the brain and is done sometimes to contain seizures, less now than before. The severing of this very important commissure in the brain virtually destroys communication between the two hemispheres. Not all communication is lost because some information is still exchanged in the anterior commissure, which is located beneath the third ventrical but is very small. I am not absolutely sure, but it is not involved in sharing between the corteces, which are the basis for conscious experience. So I dare say that the exchange of information in the anterior commissure is probably of the more survival-based kind and not the cognitive kind. (please respond to this professor!)
With the two hemisphere's cooperation center out of the way, each hemisphere can be presented with a particular stimulus and their reaction to it or ability to recall it can be observed. Classically, we are taught the visual field experiments where different objects are flashed to different visual fields and then the subject is asked to reach for a particular object. Rather than reaching for both objects, the subject reaches with his left hand toward what his right hemisphere would see and reaches with his right hand what his left hemisphere would see and express surprise to what his left hand is doing because the left hemisphere is the more expressive hemisphere. All this I already knew before I did my search (and to a large degree, the links in google are limitted to this) but there is so much more to it.
Gazzaniga reports findings that excite me. As I've understood it, the left hemisphere is responsible for language and creative processes. The right hemisphere is responsible for more logical thinking, the truth in memories, writing and illusory contours. I absolutely love my right hemisphere! Apparently the left hemisphere is very developed in rationalizing. It will make up reasons for why things are the way they are or why an object is important. Some times it will make up reasons for why the left hand chose something so different then what the left hemisphere directly experience. The most common example given for this is the chicken and the shovel example. The right hemisphere saw the shovel and the left hemisphere saw the chicken. The shovel represents snow and the right hemisphere is aware of this. But the left hemisphere reports that the right hemisphere identifies the shovel because the chicken den must be cleaned. It's plausible but wrong.
After I learned that the right hemisphere is specialized for writing and the left hemisphere is the center for creativeness, I became particularly intrigued. I do fictional writing as a hobby and, in my mind, writing and creativity go together. But they're in separate hemispheres! I really wanted to find a novelist patient who had callosumectomy done on him or her. I found no such patient but I am still looking for it. This way, I would sort of find out more about my brain and how my writing tendencies would suffer if this surgery was done on me--hypothetically. That would be thought-provoking and I hope not scary.
Particularly about the right hemisphere, I was amazed that it was responsible for illusory contours, mainly because it is not quite logic based. The reason that creativity is allotted to the left hemisphere is it's tendency to seek deeper meaning in any given event. But the right hemisphere does not do this so I was puzzled that illusions would be on the right hemisphere which is the hemisphere that "lives in the thin moment" (Gazzaniga's words). I have thought about this quite a bit. I remembered learning about lateral inhibition in an earlier class. What that is is that retinal cells inhibit one another relative to how quickly they are firing and this creates illusions of edges and lightness that are the basis of illusory contours. The fact is, this is happening on the reception level and the interpretation is involved in the processing but it begins earlier than processing. So maybe the cells that interpret this unique neural firing are localized in the right occipital lobe in the primary visual cortex. But I have a little trouble with this because, at least the way I've understood everything, the firing of neurons are carried in the receptors of each visual field and the splitting at the optic chiasm leads the information from the mentioned receptors to the appropriate visual areas in the primary and associative visual corteces. Really, this just means that both hemispheres receive the same type of information about their visual field. At least, I am not aware of any further splitting of the optic nerve that sorts according to type of data. So why is this illusion specific to the right hemisphere? You can tell I've thought long and hard about this.
I am unable to synthesize this last bit of information with the rest of the post but simply cannot help but mention it. Gazzaniga claims that the brain continues to be plastic after this surgery. He reports about a patient named J.W. whose right hemisphere eventually gained control of speech even if it did not have speech areas before. This is really disconcerting. So suddenly both hemispheres that have no contact are able to speak. It would be interesting to see this person speak.
Split brains are extremely fascinating. I feel really satisfied with my "findings" about this.
http://cwx.prenhall.com/bookbind/pubbooks/morris4/medialib/readings/split.html
http://www.pakistan.tv/videos-split-brain-patients-%5BMZnyQewsB_Y%5D.cfm
terms: commissure, callosumectomy, split brain, optic chiasm, illusory contours, lateral inhibition.
Topic: Agnosia
Agnosia fits into both AoM and to the text, for obvious reasons. The reason it relates to the text is because it very much deals with perception. Agnosia, defined, is the inability to recognize people or objects even when the sensory modalities are intact. In basic terms or translation it means non-knowledge. When we percieve certain things we can recognize what they are or what a function of an object that we see is. With agnosia, a person cannot recognize what an object is when it is presented to them. I am interested in agnosia based on the simple fact that it is just interesting. While objects to someone without this diagnosis seem to appear as obvious to their functionality and what they are, someone with agnosia cannot fully understand what they are presented with.
Agnosia is usually associated with brain injury, and depending on which hemisphere is affected can change the type of agnosia a person experiences. There are two general types of agnosia, refered to as apperceptive agnosia and associative agnosia. In apperceptive agnosia, there is a failure of pattern recognization caused by an inability to categorize objects when at a perceptual level of analysis. In associative agnosia, object recognition fails because of the difficulties in identifying the functional features that define a semantic category.
Besides these two types of agnosia there are also more narrower groups. A person can experience a visual agnosia (they are presented with visual stimulus but can't identify the object), auditory agnosia (presented with music or auditory stimulus but do not respond to it even though hearing is intact), and somatosensory agnosia (when touching an object they cannot recognize the object). With somatosensory agnosia a person can still describe the object based on it features, or even draw the object, but cannot identify what the object actually is or what it may be used for. There are many many more types of agnosia, but these are the basic forms that reach out to the other categories.
I know that this is deviating from the integration of information, but with my video link there is an actual representation with someone who has visual agnosia. In the video she is presented, in her visual field, her glasses and a key. She can somewhat describe some of the features of the glasses, but has no real idea what they are. The woman also has a really hard time grasping the object and obtaining it from the man. She seems to have a hard time with her depth perception, she cannot distinguish where the object is in the distance from her. When she finally grasps the glasses and the key she can instantly tell what the items are. Using a different part of her brain (through touch) she can tell what the item is and fully identify it.
Something I happened to find in my website search was the mention of why this might show up in an individual. While I already stated earlier that it is usually produced through brain injury, it can also happen through stroke, dementia, or other neurologial disorders. It is also mentioned that those people who have had a dramatic recovery from blindness expereience agnosia quite often, relating to what Virgil experienced in his recovery.
In AoM the man who mistook his wife for a hat, or Dr. P. was mentioned. His form of agnosia was also visual, and experienced this agnosia because of damage to his brain. Like stated earlier, there was found nothing to be wrong with his eyes...he was experiencing this solely because of his brain functions being impaired. He did not experience anything that interferred with his hearing or motor functions, so he was still able to sing and paint like he enjoyed doing before he started experiencing abnormalities in his life. Dr. P. was also a painter, and had quite a skill for it, but given his visual recognization of impairment... his before and after paintings differed greatly. The earlier ones had a sense of put-togetherness and a concept, while the later ones were disjointed and abstract.
It is one thing to spit out information, but to relate it to actual people and to see the actual affect of something on a person is entirely different. I think it is very interesting to actually see the affects of agnosia and it really helps to support an understanding of what it actually is. Agnosia is an interesting concept to process as a person who has no problems distinguishing objects, and it was a very interesting topic to research.
URLs:
http://www.psychology.sbc.edu/redwine1.htm
http://www.youtube.com/watch?v=dG8JGg-d2Pk
http://www.psychnet-uk.com/dsm_iv/agnosia.htm
..also had a little information on it in a book
terms: agnosia, apperceptive agnosia, associative agnosia, perception, semantic
I recall covering eye tracking studies in class, but I wanted to take it a step further and research how eye tracking devices are implemented in the real world. I immediately thought of occupations in which testing is used especially eye tracking. I assumed eye tracking tests would probably be used for upcoming pilots and astronauts. I was correct in this assumption and did find some interesting information on the subject.
Before going into detail on how eye tracking is used in the world one must first understand the basis of what eye tracking actually is. In class and in other classes I have learned that eye tracking is just what it sounds like it is. Eye movements can be tracked several different ways depending on the test being used. Not only is movement of the eyes recorded, but so is fixation of the eyes. Meaning what is the eye focused on and what makes the eye focus on something different.
The first site I came across was directly from Nasa and I found it exciting to see that something as simple as eye tracking is used for those who are going to be astronauts. This specific occupation can only be accomplished by a very select amount of people. This site went into detail on how they use eye tracking to prepare astronauts for space travel. Anyone who enjoys learning about this occupation would find this site very enriching. Nasa specifically uses an eye tracking device that works through a headset that has two digital cameras attached and sensors. These cameras monitor horizontal, vertical, and rotational eye movements along with the sensors that monitor head movement. The site goes into great detail on the different methods used to prepare astronauts, but also explains why these tests are important for successful space travel. Definitely check it out if you are interested in any of these topics and how the visual system can be valuable in such a job.
Another site I found is aimed towards children, but can be very helpful when talking about the visual system and eye tracking. This site is used by teachers and parents who are trying to condition children to use eye tracking in order to learn. I found this site relates to class in so many ways because it covers topics like perception, eye tracking, eye focusing, and eye teaming. Within perception children can use this site to help them with eye discrimination, visual memory, figure ground, visual closure, and form constancy. Anyone that has taken an introductory psychology course should be aware of what these topics are. Eye discrimination for example is discriminating the differences between two objects or images. Visual memory tests your memory based on images that may be flashed in front of you for a few seconds and then are supposed to be recalled in order. There are tons of different tests and games on this site that not only can help teach children about their visual system but can help them increase their visual learning.
The last site I visited was a demonstration of what an eye test may be like. It shows an example of a guy viewing a website and how eye tracking tests map out his eye movements and eye fixations. It is important to understand not only what eye tracking is and when it is used but it is also important to understand what an eye tracking test looks like. What was interesting to me is how eye tracking tests show what a viewer misses or what he ignores when looking at an image. My question is, “Does eye tracking relate to motivation or is it based more on the physiological work of the visual system?” As anyone can see there is a lot out there in which eye tracking can become an essential test. Whether it is preparing an astronaut, teaching a child, or the overall understanding and research behind eye movements.
Terms: Visual system, eye tracking, visual memory, eye discrimination, perception
http://www.nasa.gov/mission_pages/station/science/experiments/ETD.html
http://www.eyecanlearn.com/
http://www.youtube.com/watch?v=lo_a2cfBUGc
Topic: Perceptual Constancy
After reading through the chapter, the part about perceptual constancy stuck with me. In the chapter, Virgil had his vision restored after being blind for over forty years. After the surgery, he was faced with relearning many visual tasks. His brain had forgotten all the visual developments from his childhood, including perceptual constancy. This topic fits into the chapter because it is a vital component to vision that Virgil had to adjust to. I’m interested in the subject because I find the cognitive processing behind vision to be incredible. I didn’t realize seeing in three dimensions required such an exhaustive amount of neural processing.
Perceptual Constancy, also called subjective constancy, is defined as the ability for humans (or mammals) to see familiar objects as having standard size, shape, color, or location despite any changes in the angle of perspective, distance, or color. Perceptual constancy can be broken down into several different types: shape, size, color, lightness, distance, location. Beginning shortly after birth, infants are already able to discriminate between different stimuli in their environment, allowing them to learn about objects and their physical characteristics. Studies have shown this familiarity of the environment allows infants to detect the spatial differences between ordinary objects. These developments, while occurring at an early age, are extremely complex and have a significant impact on visual perception in the lifetime. In AAoM, Virgil is forced to re-develop these visual abilities after being blind for the majority of his life. And, instead of developing perceptual constancy unconsciously like in childhood, he must make a conscious effort to learn the transformations. For quite some time Virgil was only able to see colors and could not determine the shapes or sizes of objects. His fiancée Amy bought him a child’s wooden formboard where you put shapes in their corresponding holes. Virgil struggled with this activity for almost a month before mastering it. Similar difficulties relating to light were seen when he visited home for the first time after his surgery, describing the dining room table as “a whiteness to the right.” In the footnotes of page 128 of AAoM is a great quote from another person with a similar situation to Virgil’s. He never ceased to be “struck by how objects changed their shape when he walked round them . . . He would look at a lamppost, walk round it, and stand studying it from a different aspect, and wonder why it looked different and yet the same.” Perceptual constancy is based on contextual clues, meaning someone must be able to have a valid assessment of the size, shape, or distance. If, for instance, someone sees a man running away from them and can accurately perceive the distance between them and the object, the size of the man remains stable. We also see consistency in size because of how the object relates to its surroundings.
http://www.sapdesignguild.org/resources/optical_illusions/intro_constancy.html
http://books.google.com/books?id=LAtJHcBRAkEC&printsec=frontcover&dq=perceptual+constancy&source=bl&ots=tHzZU47xax&sig=uCwvF61EP3RDmwVj9MG9P4avwNg&hl=en&ei=UZybTIyUJI-bnwfqr5DADw&sa=X&oi=book_result&ct=result&resnum=6&ved=0CDMQ6AEwBQ#v=onepage&q&f=false
http://onlinelibrary.wiley.com/doi/10.1111/j.1468-0378.2010.00405.x/pdf
As I was reading the chapter, I started to realize there was a lot I did not know about being blind. As the chapter started to talk about things that were wrong with Virgil's eyes I realized that a lot can be wrong and there are different types of blindness. This is something I honestly know nothing about. No one in my family has ever been blind so I am a bit naive about the topic. Therefore, I decided to look into the different types of blindness that people can have.
The first main type of blindness I found was diabetic retinopathy. As you can probably guess from the discription, this is caused by diabetes and can occur in both adults and kids. What actually goes wrong in the eye, is that blood vessels in the back of the eye literally break. This causes blood to flow into parts of the eye that help a person see. Surgery can help with this disease.
The next type of blindness is what was talked about in the chapter, retinitis pigmentosa. This typically (as in Virgil's case) starts when a person is young and gets contiously worse as that person ages. This will leave the person blind as an adult. The beginning signs or stage is that a person has complaints about seeing at nighttime. Later their field of vision will decrease... and continue to decrease. There currently is no cure of this disease and scientists are still a little unsure on how it is formed.
Glaucoma is a disease that typically affects the older generation. Fluids tend to build up in the eye in glaucoma. This creates a tremedous amount of pressure on the eye, which then leads to nerves being damaged. An equivalent feeling to this would be when you get out of the swimming pool and you were opening your eyes under water a lot. The feeling of all the chlorine in your eyes is very comparable to glaucoma.
Macula degernation still cannot be cured and it is common in older people. In this disease the very middle of the eye (macula) is diseased. The macula is the center of the eye and is the layer of tissue that is on the inside back wall of the retina. The eyesight of this person may very much look like there is a blackhole in the middle of everything they are seeing. This particular disease can greatly interfere with recognizing faces.
Cataracts, as talked about in Virgil’s case, are something else that can greatly affect someone’s vision. A cataract is a “clouding of the eye,” so to speak. The degree of fogginess to a person can differ, but basically the cataract is minimizing how much light passes through the eye.
In one of the links in particular it talks about gene therapy and how monkeys were able to see color after the procedure done. This in particular leads to the future questioning of whether a further study in genes will one day allow us to cure other types of blindness. As in one of the links Professor MacLin has posted before, CBS did a special entitled “Blind Learn To See With Tongue.” This video is extremely interesting and gives us a further sense of what the future has in store for possible “cures” for the blind (if they are interested).
This relates directly to the textbook because it talks about eyesight, perception and how people are really seeing the world. The bottom line is a lot of people become blind later in life (meaning at one point they had eye sight). I think this particularly relates to cognitive psychology because they have previous perceptions have the world was, their senses are adapting to what they now know, and they are constantly looking for better ways to improve their “sight.”
Terms: diabetic retinopathy, retinitis pigmentosa, macular degeneration, macular, retina, glaucoma, cataract
http://www.lwsb.org/index.asp
http://www.mayoclinic.com/health/macular-degeneration/DS00284
http://current.com/shows/upstream/90947929_gene-therapy-cures-color-blind-monkeys.htm
http://www.youtube.com/watch?v=OKd56D2mvN0
Something that we've alluded to in class in the first couple weeks, but never really directly discussed was Pattern Recognition. Pattern recognition in essence is how people are able to determine whether people, places, objects, ideas are familiar are not. When it's defined like that, it's very clearly a very important part of cognitive psychology.
There are two basic types of theories that I became vaguely familiar with after a little bit of research. The first type of theory is the template theory. Template theories, in short are our brain's way of categorizing any stimulus by comparing it to a pre-existing image in our mind. For example, if we were to look at the letter L written in three different ways (bold, italicized, and normal fonts) we can recognize the letter as being "L" and not confusing it for "N" because it is similar enough to what we think L should look like. Template theories are able to recognize objects through varying sizes, orientations, and styles. Context is not something that template theories can account for, however. That being said, the second type of theory that I have become familiar with is the feature theories. Feature theories are more of an extension to template theories in the regard that you still recognize objects based on their template, but a template is made up of characteristics of the object that allow it to stand out from something else.
Pattern Recognition is very closely related to Gestalt Psychology because Gestalt Psychology studies the sum of the parts. Some of the basic principles of grouping in Gestalt Psychology are the concepts of similarity, proximity, convergence, closure, and continuation. These concepts are important for pattern recognition because they allow us to categorize stimuli. As previously mentioned having a way to identify objects is clearly the end result of pattern recognition.
An interesting take on cognitive psychology comes in a process called "chunking". Chunking is processing individual pieces of information and making them into a "bigger picture". In the case of chess, or in my preferred case; card games, chunking is the set up of moves in order to achieve a larger goal. Chunking doesn't appear to be in innate skill nearly as much as it is a skill developed with practice and time. It does however, appear to effect the rate at which pattern recognition occurs and is an important part of the pattern recognition process.
Terms: Pattern Recognition, Template, Feature, Gestalt Psychology, Similarity, Continuity, Closure, Proximity, Convergence, Chunking
http://lamar.colostate.edu/~bclegg/PY45/pattern_recognition.pdf
http://graphicdesign.spokanefalls.edu/tutorials/process/gestaltprinciples/gestaltprinc.htm
http://www.chess.com/article/view/the-cognitive-psychology-of-chess
I decided to focus on the problem of brain adaptation after injures or other brain damages, such as severe visual impairment.
Brain is a highly adaptive organ. Nerve cell change is not limited to childhood period only. Plasticity let us learn new information and acquire skills in older age as well. Learning a new language or playing a musical instrument at the age of sixty might seem to be an ordinary example, but they all require certain transformation in the groups of neurons. In the last decades the whole paradigm of the brain plasticity issues has changed. Before that it was believed that brain does not change that much during our life, so what we have from birth and manage to develop at childhood would be the only thing one could rely on for the rest of the life. Now we know that brain changes constantly, not only in young age but even in the later periods of life.
One of the most fascinating features of the brain flexibility, or plasticity, is response to the injury. Dynamic nature of such adaptation is responsible for certain recovery after injures or strokes. When a person is injured and some part of the body is amputated, certain changes in the areas responsible for motor activity of the extremity also take place. In case of blindness if a person becomes proficient in Braille, areas of the brain responsible for the perception of the dominant arm develop sufficiently. That is one of the examples how brain “remodels” itself in response to injury.
Using PET and fMRI technique researches have got interesting evidence in the support of that idea. It showed that the area where the stoke has just occurred is not active or shows very limited activity at first. But when the person tries to use the weak hand (let us say that the stroke caused damage in the motor area) PET and fMRI detects activity in other parts of the brain not normally responsible for the hand movement.
Recent studies on monkeys suffering strokes showed that intensive training results in changes in brain activity correlated with recovery. So, if a monkey had experienced a stroke that controls its hand or fingers, intensive therapy focused on the weak hand caused brain reorganization. What is really encouraging as well is that medicine can also affect changes in neuron activity following stokes.
One of the most fascinating examples of brain plasticity is life of patients who experienced hemispherectomy. This is a surgical procedure when half of the brain is removed or disabled and is usually recommended for kids with epilepsy when no medicine can stop seizures. The effect of the procedure is much better if it is performed early, but it is still fascinating: a three years old can leave the hospital ten days after surgery walking on her feet.
Thus brain plasticity is one of the most impressive phenomena in a human being.
Terms: brain plasticity, hemispherectomy, PET, fMRI, visual impairment
http://www.excite.wustl.edu/newsletters/vol%208%20neuroplasticity.pdf
http://www.youtube.com/watch?v=vbnbL_En-Cc
http://www.youtube.com/watch?v=TSu9HGnlMV0&NR=1
For this blog I decided to discover more about the interesting topic of blindsight. I came across this topic while reading the chapter To See and Not to See in the book Anthropologist on Mars. Towards the end of the chapter Virgil was suffering from Pickwick syndrome (among other things). Pickwick syndrome is described as the lungs incapability of supplying the entire body with the amount of oxygen fully needed to sustain long-term. This syndrome affects the respiratory center in the brain. During this crisis something else became apparent. Virgil had gone completely blind and he knew this, however he was still able to behave as if he could still see. He would reach for things and avoid objects! Sacks described this as blindsight. He stated that this happens if the there is something wrong with the cerebral cortex but the visual centers in the subcortex are functioning properly. What happens here is that the visual signals are perceived but it doesn’t reach the conscious level.
My research online seemed to support Sacks. Sometimes when people are (cortical) blind (have damage to the visual cortex), or are partially blind (can’t see some of their visual field), they can see some of the things that are going on but they are not consciously aware of it. Basically what happens is the information that is sent from the retinas to the midbrain, which usually sends it up to the higher processes to translate consciously, fails. The information stops at the midbrain and cannot travel the path to the higher processes.
Some state that we all have this blindsight. For example while we are driving and doing something else, like paying attention to a conversation we are in, we are not completely conscious of everything that is going on around us unless something unusual catches our attention, something noteworthy the unconscious finds important enough to send on to the conscious. We weave in and out of traffic and heed traffic laws without consciously thinking about it. Other people say that we have a sort of functional blindsight that we use while doing such things as blinking or any time we disrupt visual input. Some say that the blindsight is proof that the unconscious exists and influences human behavior.
There are numerous cases that show instances of these type of people who can tell a direction of movement, a shape, appearance/disappearance, even an emotion that a face is displaying (even though they cannot recognize the face or even the gender) but cannot, themselves explain it or have any conscious awareness of it. It’s hard to completely explain something that is so difficult to understand, but the whole concept of it is amazing.
There is another incident (caught on tape) of a man who is completely blind but when put in a hallway full of obstacles he maneuvers he’s way around it without any recognition that he saw these objects or even that he was moving around in the hallway. You can put your hand in front of the visual field that they are not able to see and they will not be able to tell you it is there, move it up and down and they can say you are moving something up and down but they can’t tell you what it is or that they even see it. Some try to explain this by stating that there are two different pathways, we need both to see consciously, if one is damaged we cannot consciously see, but we use the other pathway to correctly guess something we cannot actually see. Vision is not entirely seeing, there can be a disconnection from the capacity to respond to visual information and the actual act of being visual aware of something. It’s hard to tell what part the things we are not aware of are playing.
This phenomena can be somewhat replicated in people by using devices such as TMS but it is controversial on how close this replicates true blindsight. There is still a lot that is unknown about blindsight, partially due to its rarity. Basically, the bottom line is that the individual denies seeing anything but upon questioning can usually give the right answer. Not only do they give the right answers but often their bodies also respond in the correct manner. Eyes dilate in respond to light for instance. They demonstrate reflexes, implicit reactions and voluntary responses. The part of the visual cortex that is appears to be damaged is the striate cortex (also called the primary visual cortex or V1).
Blindsight seems so farfetched if you don’t really think about it and take the time to learn about it, but I believe that paying attention to it and researching it can provide a lot of insight to the human brain.
Terms: Pickwick Syndrome, Respiratory Center, Blindsight, Cerebral Cortex, Visual Centers Subcortex, Visual Signals, Conscious, Visual Cortex, Retinas, Midbrain, Higher Processes, Unconscious, Recognition, TMS, Reflexes, Implicit Reactions, Voluntary Responses, Striate Cortex (Primary Visual Cortex, V1), Attention, Visual Input, Cortical Blindness
http://serendip.brynmawr.edu/bb/blindsight.html
http://www.youtube.com/watch?v=RuNDkcbq8PY
http://serendip.brynmawr.edu/exchange/node/1676
http://web.ebscohost.com.proxy.lib.uni.edu/ehost/detail?vid=1&hid=111&sid=76a686f4-83aa-4f8e-9c42-1082208338ff%40sessionmgr110&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=afh&AN=50575480