What I would like you to do is to find a topic from chapter 8 that you were interested in and search the internet for material on that topic. You might, for example, find people who are doing research on the topic, you might find web pages that discuss the topic, you might find youtube clips that demonstrate something related to the topic, etc. What you find and use is pretty much up to you at this point. But use at least 3 sources.
Once you have completed your search and explorations, 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. At the end, please include working URLs for the three websites.
By now you all should be skilled at synthesizing the topical material you have obtained from the various web sites you visited. If you need a refresher please let me know.
Thanks,
The topic I chose to do was disorders of visual attention. The visual-field defect is a portion of the visual field with no vision or with abnormal vision, typically resulting from damage to the visual nervous system. If someone is unfortunate enough to lose primary visual cortex in the right hemisphere, that person will be blind on the opposite (left) side of visual space. Suppose, however, that the lesion was in the right parietal lobe. Patients with this sort of lesion would have problems directing attention to objects and places on their left. There are two clinical symptoms that manifest including neglect and extinction. Neglect is the inability to attend to or respond to stimuli in the contralesional visual field (typically, neglect of the left field after right parietal damage). Also, neglect of half of the body or half of an object. The contralesional field is the visual field on the side opposite a brain lesion (i.e., points to the left of fixation are contralesional to damage to the right hemisphere of the brain). Neglect patients behave as if part of the world were not there. A patient experiencing neglect of the left visual field will tend to name objects to the right of fization and ignore objects on the left. Furthermore, extinction is the inability to perceive a stimulus to one side of the point of fixation (i.e., to the right) in the presence of another stimulus, typically in a comparable position in the other visual field (left side). A patient with left visual field neglect would be nonplussed, but an extinction patient would be able to report the presence of the spoon. If a neurologist were to hold up a fork in one hand and a spoon in the other, however, the extinction patient would report only the object in the good field. The other object would be perceptually extinguished. In neglect, the patient may be entirely unable to deploy attention to the contralesional side of the world or the object. In extinction, the patient may be able to get attention to an object in the contralesional field if it is the only salient object. However, if there is competition from another similar object in the ipsilesional field (same side as the lesion) then the two objects compete for attention and the ipsilesionial object wins.
I chose to focus mainly on Balint Syndrome since it was a lot easier to find information on. Patients who are unfortunate enough to have bilateral lesions of the parietal lobes (that is, lesions in both hemispheres) is known as Balint syndrome. There are three major symptoms to this disorder.
1. Spatial localization abilities are greatly reduced. As a result, a patient with Balint syndrome may have a very hard time trying to reach an object.
2. Patients with Balint syndrome don’t move their eyes very much. They tend to gaze fixedly ahead.
3. Behave as if they can see only one object at a time. Extreme form of extinction or neglect, in that attending to one object eliminates everything else. This inability to perceive more than one thing at a time is known as simultagnosia.
Traditionally considered a rare occurrence, Balint syndrome usually affects the posterior parietal lobes bilaterally, and has been described after various conditions (mainly vascular, demyelinating, or infectious diseases).5 It is now increasingly recognized as a manifestation of degenerative dementia or Creutzfeldt-Jacob disease.6 While the interpretations of the cardinal symptoms may have changed during the last century, the initial descriptions of Balint and Holmes continue to be unequalled in their authoritative detail. Balint's syndrome is a condition characterized by optic ataxia (inability to move the hand to an object by using vision), ocular apraxia (inability to voluntarily control the gaze), and simultanagnosia (inability to recognize more than one object shown at the same time). In Balint's syndrome, the individual cannot look into the sides of their visual field. The visual field is the space that someone can see without moving the eyes. The patient usually has greater difficulty seeing things in the right side of their visual fields. They have great difficulty putting visual pieces of information together. As a result, they may only be able to focus on individual details of what they see. For example, when shown a picture of a forest, they may only see a tree and won't realize that what they are looking at is a forest. So these people often literally miss the forest for the trees. This visual problem is what leads people with Balint's syndrome to have difficulty seeing more than one object at a time. People with Balint's syndrome also have difficulty estimating distances in visual space and coordinating actions depending on the particular spatial arrangement. The visual difficulties in Balint's syndrome are usually due to damage to the top part of the temporal-occipital lobes on both sides of the brain. The temporal lobe is on the side of the brain by the ear and the occipital lobe is the back part of the brain. So the temporal-occipital lobes refer to the sides and back parts of the brain. In Balint's syndrome, the top part of the parietal lobes on both sides of the brain may also be affected. The parietal lobes are the middle area of the top part of the brain. There are several structured techniques that can be used to treat Balint's syndrome that provide the patient with immediate feedback. For each of these techniques, the degree of structure decreases as the task becomes more familiar. The structure decreases to levels that are more likely to be encountered in the patient's environment. But before any of these techniques can be used, the patient needs to admit that the problems exists and believe that they can learn to trust their vision. One technique involves helping the patient focus on more than one thing at a time and to improve the ability to tell things apart with vision. In this technique, flash cards are shown to the patient with two lines on them. The patient is asked if the two lines look the same or different. The answer is written on the back of the flash card. If the angles are different, the degree of difference is noted on the back of the card as well. By using this technique, the patient can get immediate feedback as to whether he/she perceives things accurately. Also, a family member can use the flash cards with the patient or the patient can use them by him or herself. Different types of flashcards can also be used to help the patient focus on the general aspect of something instead of only focusing on the details. The flashcards have a clock face on the front with all 12 numbers. Once the patient is used to this, the clocks only have the numbers 12, 3, 6, and 9 on them. Finally, the numbers are faded out and the patient is asked to tell what time it is based only on the hands of the clock. This requires focusing on the details to answer a general question based on visual information. The time is written in digital form on the back of the cards so the patient can get immediate feedback. Some patient's with Balint's syndrome only respond to part of what they see when the object(s) is close up. Thus, one strategy is to determine how far the patient can see and to place the object(s) farther away in the field of vision. In some cases, this helps the patient improve the ability to see the entire object and not just a part of it. Since people with Balint's syndrome cannot look into the sides of their visual field, techniques can be used to improve the person's ability to scan visual patterns quickly. The visual field is the space that someone can see without moving the eyes. Some techniques to improve visual ability include having the patient make wide head turns towards the areas that he/she cannot see when looking straight ahead. Such wide head turns help the patient gather more information about the environment. Reading material that is in the area that the person has difficulty seeing can be marked with an up and down red line. By doing this, the patient will see the red line and be more aware of their difficulty attending to that area of the page. This, in turn, can allow the patient to be sure to focus more attention on that particular area of the page. To improve optic ataxia (inability to move the hand to an object by using vision) exercises can be done that require eye hand coordination and manipulating objects with the hands. Using tools would be an example as would be catching a ball. Obviously, safe tools should be used and it is often helpful to start the ball-catching exercise with a ball made of crunched up paper. The patient can then progress to balls that travel faster when thrown such as tennis balls. This task can be made more difficult by bouncing the ball against a wall first.
http://archneur.ama-assn.org/cgi/content/extract/60/9/1329
http://stroke.about.com/od/unwantedeffectsofstroke/f/Balint.htm
http://www.medfriendly.com/balintssyndrome.php5
I decided to do further research on the concept of the attentional blink. An attentional blink occurs when viewing stimuli at a rapid pace and trying to pick out two specific stimuli (targets). When the second target follows the first one within 200-500 milliseconds, most people miss it. This is the attentional blink. If, however, the second target is shown immediately after the first target, the attentional blink does not happen. One hypothesis for this is called the LC-NE hypothesis. This hypothesis states that when a salient stimulus is presented, norepinephrine is released in a part of the brain called the locus coeruleus. Norepinephrine benefits the detection of a stimulus but the affect lasts for only 100 milliseconds. Therefore, the second target can be spotted within this time frame, but not after it.
There are other theories as to why the attentional blink exists. One is the delay-of-processing theory, which states that because the brain is busy processing target one, it can’t being to process target two. Another theory is the attentional capacity theory. This explains that we have an attentional capacity for things and that target one takes up all of the capacity, therefore we aren’t able to detect target two. A third theory is the two-stage processing theory, which says that there are two stages when processing rapid series. Stage one is the detection stage and stage two is the processing stage. When target one is presented, it enters stage one and then stage two, but while the information from target one is being processed in stage two, target two can’t enter the stages. It seems that all three theories are very similar, just explained in different ways. The main point is that a target can’t be detected until the first one is done being processed by the brain.
I found an interesting demo of this concept. I had to view a rapid series of numbers and look for the letters. After each series, I entered the letters I saw. I did this 30 times and then received my results. The results told me how many times (out of 10) I correctly named the two target letters. When target two was presented two numbers after target one, I correctly named target two 6 out of 10 times. When target two was presented four numbers after target one, I correctly named target two 8 out of 10 times. I had these same results when target two was presented six numbers after target one. This shows me that I had a more difficult time detecting target two when it appeared shortly after target one.
http://www.cs.kent.ac.uk/people/rpg/pc52/AB_Webscript/instr.html = demo
http://en.wikipedia.org/wiki/Attentional_blink
http://www.rit.edu/cla/gssp400/Blink/blinkinstr.html
The topic I would like to discuss more in depth from Ch. 8 is the various visual attention disorders including: neglect, extinction, and Balint Syndrome.. According to our book, neglect is the inability to attend to or respond to stimuli in the contralesional field. The contralesional field is the visual field on the side opposite of the brain damage. Neglect often occurs as a result of a right parietal lobe damage causing neglect in the left visual field. However, there are instances of the opposite as well as instances of unilateral (same side) neglect.
The medical term for visual neglect is hemispatial inattention. However, this can cause problems beyond the visual system. Some patients with hemispatial inattention may not respond to or attend to a person’s voice on the side of the neglect. This disorder can be screened for through observation and testing. One important test is the Behavioral In-attention Test (BIT). The BIT is composed of 6 subtests. The most well known subtests are: the Daisy Drawing, the Letter Cancellation test, and the Modified Clock Dial test. In the Daisy Drawing test a patient is told to recreate the drawing of a daisy. Those with hemispatial inattention will only draw the right hand side of the flower. The Letter Cancellation test is a grid of letters and the patient must cross out all of a certain letter. They will only cross out the letter on the right side and will neglect the left hand side letters. A Modified Clock Dial test is where the patient is told to draw a clock. Someone with visual neglect will draw a circle but will place all of the numbers on the right hand side of the clock. See my first link for pictures.
Another phenomenon related to neglect is extinction. Extinction is the inability to perceive a stimulus to one side of the point of fixation in the presence of another stimulus, typically in a comparable position in the other visual field. This is different from neglect because the patient may be able to attend to an object if it is the only salient one in the person’s visual field. The problem occurs when there is competition from another similar object in the ipsilesional field (same side of the lesion). The ipsilesional field object will win the attention of the visual system. It often happens that neglect and extinction co-occur. However, there are instances where they do not. This suggests that neglect and extinction may have separate neural pathways or are located in different areas of the brain.
Some people with hemispatial inattention suffer from anosognosia. Anosognosia is an impaired or lack of awareness of their own illness. In other words patients are not aware of their disorder. This issue is common among those with hemispatial inattention because the disorder is a result of damage to the right hemisphere of the brain. President Woodrow Wilson is a famous case of someone who developed left hemispatial inattention after suffering two strokes. However, he denied he had a problem even though his case was fairly severe. He was a neglect patient that would not respond to someone’s presence or voice unless they were on his right side.
Terms: neglect, contralesional field, hemispatial inattention, Behavioral In-attention Test (BIT), extinction, ipsilesional field, anosognosia
http://www.hemianopsia.net/visual-neglect/
http://en.wikipedia.org/wiki/Hemispatial_neglect
http://www.psy.ed.ac.uk/people/rmcinto1/COiN%20Milner_McIntosh%202005%20uncorrected%20proof.pdf
http://www.treatmentadvocacycenter.org/index.php?option=com_content&task=view&id=27&Itemid=56
For this week, I decided to look further into the topic of simultagnosia. Simultagnosia is defined in the text as an inability to perceive more than one object at a time. Simultagnosia is a consequence of bilateral damage to the parietal lobes. Simultagnosia is also one of the symptons of Balint's Syndrome. Balint syndrome is very rare and occurs when there are bilateral lesions of the parietal lobes (lesions in both hemispheres). Before I delve into describing Simultagnosisa, I will explain a little bit about Balint syndrome.
Balint Syndrome was discovered in 1909 by Rezso Balint. Balint was a neurologist and psychologist from Hungrey. There are 3 main symptoms to Balint syndrome. They are:
1. the spatial localization abilities of patients with balint syndrome are greatly reduced. As a result, a patient may have a very hard time trying to reach to an object
2. Patients with Balint syndrome don't move their eyes very much. They tend to gaze fixedly ahead.
3. patients with Balint syndrome behave as if they can see only one object at a time. This seems to be like an extreme form of extinction or neglect, in that attending to one object eliminates everything else. (Simultagnosia).
People with Balint's syndrome also have difficulty estimating distances in visual space and coordinating actions depending on the particular spatial arrangement. A good example that I found of describing Balint syndrome is like is that when someone with Balint syndrome is shown a picture of a forest of a trees and all the person sees is a tree, and are completely unaware that they are looking at a picture of a forest.
When doing my research on Simultagnosia, I had a hard time finding useful information. I did find an interesting case study about RM. This article focuses on Balint Syndrome, but does briefly mention Simultagnosia. If you are interested in Balint Syndrome, it is defiantly worth reading.
The interesting thing about Simultagnosia, is that if you present two different objects to someone who has simultagnosia they can only recognize one object at a time. However, if those same objects were shown to that person at separate times, they would be able to recognize them. They only have problems when they are presented at the same time. the origin of the name comes from the words simultaneous and agnosia. Agnosia as we remember is the failure to know something.
http://www.medfriendly.com/balintssyndrome.php5
http://scienceblogs.com/developingintelligence/2007/06/dissolved_space_the_strange_ca.php
http://www.bookrags.com/tandf/simultagnosia-tf/
From chapter 8 I decided to talk about disorders of visual attention and specifically about simultagnosia. It is an inability to perceive more than one obect at a time. Simultagnosia is a consequence of bilateral damage to the parietal lobes.
The auditory environment i split sometimes into discrete and unconnected elements: street sounds, domestic sounds, or the sounds of animals, for example, might suddenly stand out and preempt attention because there are isolated, not integrated into the normal auditory background or landscape. Neurologists refer to this as simultagnosia, and it is more often visual than auditory.
Patients suffer from simultagnosia can recognize objects or details in their visual field, but only one at a time. They cannot make out the scene they belong to or make a whole image out of the details. They literally cannot see the forest for the trees.
After searching about this disorder I found some comment of people who are simultagnosics. One of them
got it after a brain injury. He said that many times he uses the forest and tree expression to describe his disorder but it is very rare disease that people do not really understand it well.
Simultagnosia is the symptoms of balint syndrome that was discovered by Blint in 1909. There are three major symtoms of it: patients with balint syndrome do not move their eyes much. they do have very hard time to reach an object, and finally, the one that I am interested the most , inability to see more that one thing at a time- simultagnosia. It is very hard find useful information about simultanosia since it is very rare disorder.
How to treat balint syndrome? There are couple approaches to do that. The remedial approach aims to restore the damaged CNS by training in perceptual skills. Tabletop activities and sensorimotor tasks are suggested for this approach. The intended outcome of this approach is to generalize skills to everyday living. The next approach is called the multicontext approach. This approach involves practicing a targeted strategy in an environment with varied tasks and movement demands. It also incorporates self awareness tasks.
http://archneur.ama-assn.org/cgi/content/extract/60/9/1329
http://brain.oxfordjournals.org/content/77/3/373.extract
http://iospress.metapress.com/content/fpg7p1q3ea0k8b64/
One topic that I found interesting was selective attention. Selective attention is the focusing of one’s conscious awareness on a particular stimulus. The idea of selective attention was first found by a Dutch psychologist named de Groot during the 1940’s. He was conducting experiments that required chess players to reproduce chessboards mid- game. The experiment showed that there was no difference between people who were good at chess and those who were not good. Our senses take in billions of bits of information every second, this seems quite overwhelming, but our brain only processes about 40 of these billions. Selective attention is thought to be a trait that is learned and developed. The evidence for this theory is that small children often lack the ability to control their attention and are often easily distracted. Children start to learn this skill around 18 months, and continue practicing and using it through out the lifespan. When looking at how selective attention works we must focus on two mechanisms that affect attention: cognitive and perceptual. The perceptual considers the ability to perceive or ignore stimuli that are both task related and non task related. Research found that when there are a lot of stimuli, especial a lot of task oriented that it is easy to ignore the irrelevant ones. However, when there are few stimuli it is sometimes difficult to ignore irrelevant stimuli. Cognitive refers to the actual processing of the stimuli, this ability to process declines with age. Selective attention is sometimes a problem because only certain people are actually capable of focusing on two separate stimuli, but many people falsely think that they can do it. This is sometimes the case of auto accidents where drivers are focusing on something other than driving.
Sources
http://www.csun.edu/~vcpsy00h/students/arousal.htm
http://en.wikipedia.org/wiki/Attention#Selective_Attention
Video
http://www.youtube.com/watch?v=vJG698U2Mvo
I found the fusiform face area interesting. The fusiform face area is in the fusiform gyrus of the extra striate cortex that respond’s strongly and prefers faces on an fMRI. This is an example of attentional selection in which attention is focused on specialized processing. Brain researchers believe that functioning of this area is not only related to the development of normal social interactions, related to defects such as prosopagnosia, but also related to reproductive success because it presents an evolutionary advantage. The face-specificity hypothesis states that the brain is specialized and contains specific mechanisms for processing specific stimuli. This competes with idea of general purpose mechanisms which are able to work with any kind of information. Kanwisher and Yovel state that the disorder prosopagnosia in which individuals are unable to recognize faces after brain damage supports the idea of the face-specificity hypothesis. Kanwisher and Yovel claim that the fact some prosopagnosia patients are unable to discern faces but can recognize other objects supports the specificity of the fusiform face area. Interestingly, research has also shown the face inversion effect which individuals have a reduction in ability to recognize faces that have been inverted as well as a part-whole effect which is a phenomena of individuals improving their ability to determine which facial structure was previously presented when those facial structures are presented in the context of entire faces. Some researchers believe that these phenomena support the idea that faces are processed as a whole as opposed to processing each individual feature separately! The expertise hypothesis attempts to explain this by stating that our experience with faces actually leads to the processing of faces as whole rather than individual pieces. The expertise hypothesis was supported by dog experts showing the inversion effect with dogs, but apparently replication has proved difficult with this study. Which makes researchers think holistic processing (processing stimuli as a hole) is somewhat unique to faces and therefore supports the face-specificity hypothesis. Face recognition is a fast phenomenon, occurring by 200 ms or earlier and although the fusiform face area is the largest face specific area in the brain, two other areas have been discovered as well. The fusiform face area is believed to concentrate on three parts of facial stimuli: the arrangement of two horizontal parts above two vertical parts, specific facial structures, and the overall contour. It is amazing to me that the visual system and the brain can have specific mechanisms for recognizing faces. Not only does the brain seem to have a preference for faces but it seems to process faces in a way it processes no other information. That is not to say that the fusiform face area is only used for faces but the activation of it is nearly twice as strong for faces than other objects. Some researchers has even provided evidence that when presented with binocular rivalry, the face will be preferred. Spector et al looked at the activity of the fusiform face area in comparing differentiating faces and other objects (i.e. types of cars) and found no correlation between the fusiform face area and other objects which is once again support of uniqueness of facial recognition. Even more astonishing is despite the importance of the fusiform face area, some individuals with prosopagnosia have seemingly functional areas in their brain. Recent research has suggested that even the mere detection of faces is enough to stimulate this area of the brain. Needless to say the fusiform face area seems to be an important piece of the puzzle as to how we detect and identify faces. Due to the importance of recognizing faces in such a social culture understanding how this phenomena occurs is important from clinical perspective. Evidence suggests the area is abnormal in cases of prosopagnosia and agnosia. Although, I found there was some debate over the issue, replicated studies have found hypoactive fusiform face areas in individuals with autism as well.
http://web.mit.edu/bcs/nklab/media/pdfs/RSTB20061934p.pdf
http://infantlab.fiu.edu/Courses/Fall%202009%20DEP%205118/Schultz_Internationl%20Journ%20of%20Dev%20Neurosci_2005.pdf
http://www.tsolab.org/nrjclub/040602/kanwisher04.pdf
I chose to look more into disorders of visual attention. Without attention, we couldn't function properly or recognize objects. Visual-field defect is a portion of the visual field with no vision or with abnormal vision. This may be because of damage to the visual nervous system. This is when there is a blind spot within the normal field of one or both eyes. If someone loses primary visual cortex in the right hemisphere, they will be blind on the left side. There may be different causes with this problem which include glaucoma, vascular disease, tumors, and other problems as well. Since the right and left visual fields overlap greatly, it might not even be known that a person has this problem until specific testing is done.
Another problem is neglect. Neglect is the inability to respond to stimuli in the contralesional visual field (neglect of the left field after right parietal damage). Also, neglect of half the body of half an object. (The contralesional is the visual field on the side opposite a brain lesion). In other terms, a person is able to see everything binocularly, but somehow ignore objects on a certain side. This impairment occurs in the parietal lobe and may often result because of a lesion in the brain (like a stroke). Extinction is another problem related to neglect. This is the inability to see a stimulus to one side of the point of fixation in the presence of another stimulus. This is similar to neglect and also involves the parietal lobe.
Balint Syndrome is another problem with three major symptoms. They may have a problem trying to reach an object because of spacial localization. They don't move their eyes much and tend to just gaze ahead. They also act as if they can only see one object at a time. One object eliminates everything else. This is a stronger theory of neglect. This is called Simultagnosia.
http://www.britannica.com/EBchecked/topic/630842/visual-field-defect
http://medical-dictionary.thefreedictionary.com/visual+neglect
http://encyclopedia2.thefreedictionary.com/Simultagnosia
For my Topical blog I chose to research more on disorders of visual attention. A visual field defect is a portion of the visual field with no vision or with abnormal vision, typically resulting from damage to the visual nervous system. A form of this would be neglect. This is a inability to attend to or respond to stimulis in the contralesional visual field( if you have damage in the right hemisphere you will have problems in your left visual field.)Also, neglect of half of the body or half of an object. Another form would be extinction. This is the inability to perceive a stimulus to one side of the point of fixation in the presence of another stimulus, typically in a comarable position in the other visual field. In an experiment with extinction, patients were influenced by expectancy as to where a stimulus is likely to occur based on the preceding stimulus contingencies. They were not influenced by the lighting size or duration of the target.
If the person has lesions in both hemispheres, they would have balint syndrome. This has three major symptoms.
1) saptial localization abilities are greatly reduced. As a result, the patient would have difficulty reaching the object.
2) patients with balint syndrome dont move their eyes much. Patients are known to gaze in a distance.
3) they act like they can only see one object at a time. Resembles an extreme case of extinction or neglect.
Along with these symptoms, if they have the inability to perceive more than one thing at a time it is known to be simultagnosia.
Some treatments for balint syndrome include adaptive functional approach where the individual's strengths are used to address his or her difficulties. The remedial approach aims to restore the damaged CNS by training in perceptual skills. The intended outcome of this approach is to generalize skills to everyday living. The third approach is called the multicontext approach. This approach involves practicing a targeted strategy in an environment with varied tasks and movement demands. It also incorporates self awareness tasks.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2700719/
http://wiki.healthhaven.com/Balint%27s_syndrome#Case_Studies
http://brain.oxfordjournals.org/content/123/6/1263.full
visual-field defect
neglect
extinction
balint syndrome
simultagnosia
As I am trying to finish up homework on a Friday evening, I find myself increasing distracted by the TV, following random links to entertaining but articles, and facebooking. While a textbook can hold my attention for only so long, I could do such things all day.
After the last chapter, I hastily formulated ideas of why this is. Textbooks have a large set size of one stimuli that are similar, words. It takes time and effort of our brain to look at everyone word and obtain meaning from it. To get a whole understanding from within textbooks, one cannot exclude or ignore a lot of information that is more complex or uninteresting. We have to actively direct our attention in books.
However, the internet is not like that. Websites and Facebook seem suited for our attention span. We can easy divide our attention between the internet and other things. Furthermore, it utilizes our covet attention shifts that we are able to process large amount of information at one time.
I think that it is also the way that information is given on facebook and websites that hold our attention. Although facebook is make up with useless information, the lay out is constantly being redesigned. The article “Why does Facebook keep changing its format? Thoughts, History and More”, states that our generation has been geared to enjoy high stimuli. It has become a high moving program, with refocused in communicating information in commenting and updates of friend’s newsfeeds.
The article “A textbook Example of What’s Wrong with Education” states there needs to be a refreshing to textbooks tool. Information in textbooks have fallen short of their important role as a tool in education, in the lack of unique data and the way it is presented. The article proposes switching up the tradition textbook by adding different physical resource and interactions, and videos, or possibly formatting textbooks online and allowing commenting on textbooks over the internet. Furthermore, new articles every day for like a newspaper to keep interesting students.
After starting to write this comment, I realized these ideas are not new ones. The introduction of electronic books and Ipads followed laptops as the new necessity in education. The article “The future of Learning” likes the idea of paper and print too. Combining the traditional textbook and also online interaction. It propose making it so we can enjoy lots of stimulation while still learning. This way students will enjoy learning more.
From Facebook and classes that work in groups, I see the value in social interaction in education. That we can learn completely new and unique things by listening to another person’s ideas on a subject and this holds our attention in the subject more.
http://www.convergemag.com/edtech/The-Future-of-Learning.html
http://www.edutopia.org/muddle-machine
http://www.reddit.com/r/reddit.com/comments/848kt/why_does_facebook_keep_changing_its_format/
This week I chose to look further into change blindness. I was able to find 2 sites with a lot of information anda 3rd site is a link to a demonstration of a flicker test which I'll talk about later. The demonstration was pretty interesting. I play a lot of photo hunt games where I have to find the differences between 2 pictures, it's not very difficult if they are next to each other. But if you have to look at the pictures separately the task difficulty increases dramatically. Try it out and see how you do.
"Change blindness is the failure to notice a visual change in our field of view". Change blindness can occur even when the change in a scene is large, constantly repeated or known to the observer. Once the observer knows that the change is occurring it is extremely obvious when looking again. The idea that focused attention is needed to see a change can explain change blindness. If attention is not given to the point of change than it can easily go by without being noticed. This idea shows that change blindness can be a useful way to study visual attention and that our "conscious experience of a scene does not involve a representation in which all events are faithfully represented; instead, representation of objects and events may be created on a just-in-time basis by the careful management of attention".
There are two different theories of change blindness. The two theories are known as the top-down hypothesis and the bottom-up hypothesis. The two theories refer to what it is about the change of the scene that gets our attention. In the bottom up hypothesis it is focused on the visual salience of image components. This includes the basic elements of our visual processing such as movement, lighting, and contrast. The top down theory focuses on our "understanding of the context of a scene". For example, if you are looking at a picture of an office and are told to find the computer you're attention will most likely be focused on the desk because we understand that it's where the computer will probably be. With change blindness both of these theories do seem to be working together. We use top down knowledge to focus on things of interest in the scene (the computer) but at the same time our attention can be easily refocused on a change in lighting or with movement. When we focus on these 2 things it's easy to miss changes elsewhere in the scene. We only have so much visual and cognitive processing resources. Therefore it is easier to miss changes if we are not focusing on the specific object that is changed.
Researches have been looking at change blindness for many years. Recently, researchers are arguing that prior research on change blindness was contaminated by unintentional changes. These researchers created a computer algorithm to make changes to a picture without making changes to the overall visual salience of the scene so they can better separate the two variables. The researchers used a flicker test which is showing a scene taking away the scene and then showing the same scene again with one change. Past research showed that it is more difficult to see the changes when there is a gap in between the scenes then when one scene is immediately followed by the changed scene. The final link I'll post shows an example of a flicker test that you can try for yourself. The researchers showed that people are more perceptive to changes involving removing or replacing objects that they are to objects changing colors.
A closely related phenomenon that is often confused with change blindness is inattentional blindness. "This is the failure to experience an object or event that is easily seen once noticed". This generally occurs when you are focusing on an attentionally-demanding task and you do not expect the event or object. The two forms of blindness are similar but change blindness involves second-order information (the transitions between quantities) and inattentional blindness involves first order information (the presence of quantities). The two refer to different aspects of the visual world. Other aspects of change perception that can be distinguished are detection (determining that a change has been made), identification (determining what kind of change was made) and localization (determining where the change was made). There is also the ability to determine what item changed. Failures in each of these visual aspects have ben found, change blindness generally refers to the failure to detect the change.
Link to example of inattentional blindness: http://www.youtube.com/watch?v=Ahg6qcgoay4
Information about change blindness:
Check out the first two links on this website, they're both good
http://theness.com/neurologicablog/?p=2061
http://www.scholarpedia.org/article/Change_blindness
This website has a demo to test change blindness.
http://www.gocognitive.net/demo/change-blindness
I also found change blindness or the failure to notice a change between two scenes if the meaning of the scene is not altered. I thought you might enjoy this pretty cool video on NOVA I saw about it.
http://www.pbs.org/wgbh/nova/body/change-blindness.html
People with Balint's syndrome also have difficulty estimating distances in visual space and coordinating actions depending on the particular spatial arrangement. A good example that I found of describing Balint syndrome is like is that when someone with Balint syndrome is shown a picture of a forest of a trees and all the person sees is a tree, and are completely unaware that they are looking at a picture of a forest....So does the eye take a horizontal view and squeeze it into a very skewed vertical view? Or is it because their gaze is so focused on the object. The fovea which is located directly behind the pupil and lens is the area of the retina that provides the greatest degree of visual acuity. The fovea must be blown...like a fuse
My topic of interest is neglect. Neglect is a deficit in visual attention. Chapter 8 is about attention and scene perception and neglect has a large part in scene perception. When damage is done to the right parietal lobe a person will have an inability to attend or respond to stimuli in the contralesional visual field typically to the left visual field. Visual neglect is a common neurological disorder in which patients fail to attend to, report or represent information appearing in contralesional hemispace, despite intact sensory processing and visual acuity. Hemispatial neglect is a common result of stroke, particularly after right-hemisphere brain damage (RHD), with reported incidence over 80% following lesions to the right middle cerebral artery. Hemispatial neglect can be debilitating in everyday life. For example, after a right-hemisphere lesion, neglect patients may fail to notice objects on the left of a scene, words on the left of a page or food on the left of a plate. In the laboratory, these patients show an ipsilesional spatial bias in many simple paper-and-pencil tests; they deviate towards the right when asked to bisect a horizontal line at its midpoint and omit to copy or draw features on the left of a figure while preserving the corresponding features on the right. I am interested in this topic because I did not realize how common this inability was and how it could impact peoples life.
Some researchers have reported that different degrees of impairment are associated with different visually guided movements. Neglect patients who showed a strong rightward bias when pointing to the judged center of a rod but showed little neglect when a grasp response was used. This advantage for grasp over pointing responses occurred only when performance was guided by on-line visual feedback. While this possibility seems counterintuitive, one must keep in mind the fact that perceptual representations are not only utilized for object perception but also for “perceptual–motor” tasks like pointing. The pointing tasks described earlier require patients to “show” the experimenter the middle of the rod— a very perceptual concept. Hemispatial neglect may, therefore, disrupt perceptual representations while sparing the visual motor networks guiding grasping. While some neglect patients may be able to successfully pick up an object they have difficulty perceiving in its entirety, it does not mean that they are picking up the object in the same way that an intact individual would.
Article: http://www.cnbc.cmu.edu/~behrmann/dlpapers/Marotta.pdf
Video/ Human: http://www.youtube.com/watch?v=ymKvS0XsM4w&feature=related
Video/ Animal: http://www.youtube.com/watch?v=hHo-y7WJIlU
Attentional cues are interesting to me and I decided to to try to investigate them. Artificial cues are used in a lot of attention research to draw the "spot-light" to a particular area in the visual field. The kinds of cues I am interested in are natural cues that occur, and automatically and unconsciously directs our attentional resources to something in the visual field. I noticed my attention being cued while sitting in a very dark bus at night. I was staring straight ahead for the most part and the person next to me was periodically texting on their phone. I began to notice that every time they flipped open their phone and the light came on, my head would turn and I would look directly at the light. I did it many times without noticing and it happened immediately. When i noticed I was worried that the guy next to me thought I was a creeper and was trying to read his text messages. The point is that the light automatically directed my attention to it. My guess is the massive contrast between light and dark was the cue.
Gaze cue is a phenomena that occurs when we are with other people. Basically if we notice another person's eyes do a saccade, or make a large jump, we are very likely to look in the same direction they looked. It seems like we recognize the attentional cueing process in other humans and have developed a cue based on this information. An article in science daily cites a study that found political liberals were more affected by gaze cues than conservatives. Apparently the researchers suggested that conservative's beliefs of personal autonomy may have contributed to their reduced chance of being subject to gaze cues. Maybe it runs along the lines of expectations, although I doubt this explanation is very accurate. It is interesting that a perceptual difference exists across political variables.
An article released by the APA cites a study in which children's abilities to harness gaze cues was tested. The children were told a ball was under a cup, and a confederate lied to them about which cup the ball was under while keeping their gaze fixated on the cup the ball was really under. Kids above age 4 were usually able to use the gaze cues to detect deception and find the location of the ball, while children under 3 were not able to detect deception. It would seem that somewhere in this age range we begin to make associations that allow our cognitive skills to recognize gaze cues. This phenomena is interesting because it is both cognitive and social in nature demonstrating that so much of our cognitive adaptations have arisen from the need to be a social species.
http://eastanglia.academia.edu/ABayliss/Papers/404808/Gaze_Cues_Evoke_Both_Spatial_and_Object-Centered_Shifts_of_Attention
http://www.sciencedaily.com/releases/2010/12/101209074403.htm
http://www.apa.org/monitor/dec04/deception.aspx