Visual processing and the mind: A simple brain test for AS?!

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There is some new research coming out about the perceptual differences between local and global processing in Autism.
It may be soon possible to take a simple EEG to determine if you have "Autistic brain wave" patterns, since autistics have a unique difference in how the visual pathways are processed in the brain. In my opinion, understanding this aspect of Autism is VERY IMPORTANT, and not enough research has been done on this.

Some of this is confusing to understand, since many people are not familiar with cognitive psychology, so I decided to write an article about it. I hope this makes the picture a little less fuzzy.

Here are is some of it, but the images are in the blog so I suggest you read the blog so you can take the tests too!
http://beingnearlyhuman.blogspot.com/20 ... r-way.html
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There is interesting new research being developed looking at different types of information processing in autism. Using an EEG, researchers have found that people on the autistic spectrum have particular differences in "brain waves" while performing certain tasks, meaning soon there could be a simple physical test that can aid in the diagnosis of autism.

Many people have the vague understanding that the mind sees through the eyes, and that information is transferred into the brain via some kind of recording device, which is then displayed as one image on an "internal screen."

However, the brain actually perceives the outside world with multiple processes. There is no recorder, and there is no screen. We only have the illusion of a unified field of vision.

Sometimes, these processes/pathways do not operate in synch. Some may be slower than others, and your brain might experience perceptual "lags", which may be responsible for communication difficulties and sensory difficulties. It's like playing a video game, and the characters are lagging behind you and the scenery.

Similar to your eyes seeing from different perspectives and coming together as one sense of vision, the two hemispheres of your brain are associated with two different ways of seeing. One side, the left hemisphere, is able to quickly process colour and detail. This is called "local processing". The other side, the right hemisphere, is concerned with whole objects and boundaries of objects, called "global processing", and is important for other processes such as motion detection and depth.

In "neurotypical" people, these two distinct pathways come together as one, but in autistic spectrum disorders, there are discrepancies with how these two different viewpoints merge. In the normal brain, the brain is first concerned with the object as a whole. It only "zooms in" to consider the detail, if the object is being examined by you. For people with autism however, the brain is usually fixated with the detail oriented, "local processing" mode first, before it begins to perceives the whole object.

The easiest way to demonstrate and understand this is using a test called "The Navon test".

The first figure "neurotypical" people usually perceive, is the large letter made up of the different small letters. This image at first glance would appear to be "E S A H", then they would realize these images are composed of other letters.

In autistic spectrum disorders (as well as other connective disorders, such as schitzophrenia), the person first perceives the small letters instead of the whole. This image appears to be a collection of "A H E S". They are able to understand the whole as well, but there is a delay in being able to see the whole. (For example, I may scan the edges of the group of "E" to see the letter A, but if I concentrate for a couple seconds the entire A appears. Then after a couple seconds it may "Pop", and disappear, and I see a collection of E again.) This means to me, many objects appear to vibrate. ) This delay in perception is detected with the use of an EEG.


See how fast you are able to find the triangle in the baby carriage. People with enhanced local processing are able to find it more quickly than people who tend to see things in wholes.

(If you find you aren't sure if you have Asperger's or not, and you have no difficulty seeing the wholes, then you might not have an autistic spectrum disorder. MOST have these issues, but apparently, not ALL.)

This can create problems in daily life, such as inability to properly understand facial expressions (since you may not view the face as an entire whole), and navigating. When your brain has trouble detecting the boundaries of objects, its more difficult to navigate around objects and interact with them.

Don't confuse this, with visual focus. Focus happens within the eye. This is how the brain processes what the "eye sees". (I know, confusing.)

This aspect of processing in autism is often overlooked by professionals, and those attempting to understand the nature of autism. But in my opinion, understanding how these pathways work, and WHY there are delays in processing, is a very important part of Autism research, and much more work needs to be done on this.

This is because visual perception and internal thought patterns are intimately related. Your ability to perceive the world reflects how you are able to perceive thoughts in your own mind, and the information you are attempting to understand. Our ability to "think" was adapted from the older visual pathways of our primate ancestors.

It is my belief that deficits in the ability to perceive wholes is directly related to other aspects of autism- such as trouble with metaphors and abstractions, "one track thinking", the feeling that the world is "chaotic", and the tendency to have "special interests".

This is because an autistic brain has a much easier time putting small pieces together, both visually and mentally. Just like there is difficulty in perceiving objects quickly, many autistic people have a hard time quickly changing topics or "areas of thinking." They aren't able to quickly scan the whole "concepts" in their brains, like neurotypical people do. They get fixated on the small details and connections.

The ability to see objects first globally instead of by their parts, is a newly adapted human trait. Our closest cousins, Chimpanzees, show only slight preference, or no preference for global processing. Monkeys do not have this ability, they process the world more like local processing. It seems to me, that global processing and the mental equivalent, the ability to "conceptualize", was probably very important in our evolutionary past, helping us to form relationships, learn to avoid predators, and form complex community and groups.

(I'm in no way implying that autistic people are less evolved or something! I'm just saying that a lot of our brain wiring is evolutionary very new. In this way, what Temple Grandin says about Autistics being able to think more "like animals" may be true.)

interesting.

When I look at the letters, I seem to see both the overall pattern, and the letters making up the pattern, simultaneously. If I try to NAME the overall pattern, though, I invariably name the smaller letter which makes up the pattern and have to correct myself: "What is this letter? "A" . . . no, it's an "E". The little letters are "A's"."

When I look at the baby buggy, I immediately perceive a total of 11 triangles, but none of them corresponds to the example shown, which I assume we are attempting to match.

That's interesting. I found it almost difficult to perceive the larger image. My sight immediately zoomed in on the smaller ones.

The first thing I saw was the little letters and not the whole until some time later. My NT BF saw the wholes first. Good test!

Same here on the baby carriage. I immediately noticed many triangles and then later noticed one that matched the equilateral triangle used for example. I had no trouble processing the baby carriage as baby carriage first. I did not see it as a bunch of triangles and then a baby carriage.

How could someone see the whole letter and not the little ones first? That is crazy.

I'll post the images anyway so people that just want to take the tests can find them easier:



Did you see the big letters or the little letters first?




See how fast you are able to find the triangle:
http://labspace.open.ac.uk/file.php/477 ... 1_002i.jpg
(it keeps breaking the image, but it works fine)

Even after I see the larger letters, my brain wants to see them as just groups of smaller letters that coincidentally happen to resemble larger ones.

The only place I can identify a triangle that looks like the example is an area made up of, or trisected by several smaller ones that don't.

I see the large letters first.

I saw all the little letters first until a few seconds later I realized they were forming big letters.

The baby carriage confused me because there are so many triangles, I wasn't sure which one I was supposed to find.

I wonder if the Navon test would have to be recalibrated for synesthetes somehow. I can't help but see the little letters because the colors "light up" in my mind, and contradict the color I would expect from the larger figure, which causes a delay and keeps making it try to "snap back" to just taking notice of the small letters. I can get it to change pretty quickly, but the color of the little letters is VERY dominant.

I can't get the image of the carriage to open...

_________________
Official diagnosis: ADHD, synesthesia. Aspie quiz result (unofficial test): Like Frodo--I'm a halfling? 110/200 NT, 109/200 Aspie.

Small letters first, and the triangle was easy to find.