Understanding the way your child’s brain works is crucial to being able to provide an optimal learning environment. Below is a brief overview of some of the research about the brains of people with autism. Then you’ll find easy, practical ways to implement this knowledge and create an optimal learning environment at home.
Autism is referred to as a “spectrum disorder” because there is such a wide variation among people with the diagnosis. Researchers using technology that allows them to be able to see how our brains are structured also see that the brains of people with the label ‘Autism’ are vastly different from one another. Because of this, some scientists have suggested we need to look below the level of the brain’s structure to the way individual neurons (brain cells) are wired to find the “miss-wiring” that affects all people with autism. Researchers have found evidence that the way some neurons are connected in the brain of people with autism may lead to a low signal-to-noise ratio. This means that many of the signals brain cells are sending to each other may be accompanied by “noise”, like static in a radio signal. This is one explanation for why children with autism become hyper-aroused (overwhelmed) by sensory information and why they may find it more challenging to choose between two different sources of information. For example, it is often more difficult for a child with autism to be able to listen to the teacher when other children in the class are making noise. Studies recording brain electricity in autistic people have shown that even when they are trying to ignore certain aspects of their environment (such as noise in the classroom) their brains respond to this information in the same way they respond to the information the child is trying to attend to (the teachers voice). The problem for many children with autism seems to be one of “filtering”, that is, they are less able than typical children to filter out sensory information that is irrelevant to what they are trying to focus on.
The result of this is that all stimuli are given equal priority by the brains of those with autism, causing an overwhelming flood of sensory information that the child must handle. The brains of typical children learn to filter out irrelevant stimuli early on in life, so by the time that they go to school, children are able to focus their attention on what they are asked to focus on. It is very hard for many children with autism to learn in environments where there is a lot of competing sensory information (including noises, sights, touches, smells, etc.) such as a classroom.
Children with autism are taking in a lot of information all the time; this means that at some stage, they have to sort through this information to see what they really need. Studies have seen that people with autism tend to do the sorting through at a much later stage in processing than neurologically typical people. This is like going down the aisles in the supermarket and putting one of everything into your cart, then arriving at the checkout and discarding what you do not want to buy. This causes a “processing bottleneck”. Studies using technology that allows us to see which parts of the brain are being used in particular tasks help us to see that this is what is happening inside the brains of people with autism. There is more activity in the brain regions 自閉症測試 designed for lower-order processing (going through the supermarket aisles) than in brain regions for high-order processing (moving through the checkout and going home with the items on your list). This may explain why children with autism often show significant challenges in areas of high-order processing (e.g. memory, attention, organization, language, etc.), because they spend so much time trying to deal with the basic incoming sensory information that they don’t get time to practice the high-order thinking processing other children their age are practicing. Thus the brain of the child with autism starts to develop differently than the brain of his typical brother. There is some evidence that this processing style is already present when children with autism are born, even though the concurrent behaviors may not be recognized until 18-24 months later.
Psychologists call this style of processing (over-relying on lower-order processing) “weak central coherence.” Central coherence describes the ability to process incoming information in context, pulling information together for higher-level meaning often at the expense of memory for detail. Weak central coherence then is the tendency of those with autism to rely on local feature processing (the details) rather than taking in the global nature of the situation. For instance after viewing identical pictures and then being asked to remember what was in the picture a typical person might describe the scene as “a forest at sunset” while a person with autism might remember “shiny leaves, orange light and a branch you could hang a swing from”. This processing style is the reason people with autism outperform people without autism on specific tasks. One of these tasks is The Embedded Figures task. In this task, people might be shown a line drawing of a car which everyone can identify as such. When asked to point out the three triangles in the picture, people without autism are much slower than those with autism. This is because the typical people can not see “past” the car to label all it’s constituent parts. The people with autism will identify the three triangles quickly because this is how they are practiced at seeing the world.
Research involving people with autism ranging from studies of how individual brain cells are connected to how people perform in psychological tests paints a picture of the world occupied by those with autism as fragmented, overwhelming and filled with “noise”. This is corroborated by autobiographical reports from people with autism. Understanding the autistic child’s fragmented and overwhelming world shows how important a child’s external environment is when designing treatment and education for children with autism. It also explains why children with autism crave order and predictability in their physical environments.
Physical environments with higher amounts of sensory stimulation (e.g. bright visual displays, background noise, etc.) will add to the “noise” in an already overloaded sensory system making any new learning extremely challenging–like trying to learn Japanese in a shopping mall. The extent to which rooms can be tailored to meet the needs of these children is highly limited in a typical classroom setting, mainly due to the presence of other children and the subsequent size of the room. Even fluorescent lighting has been shown to affect the behavior of children with autism. These environmental considerations are either overlooked and their importance underestimated when placements are suggested for children with autism or it is beyond the scope of the school district to provide any other type of physical environment.