Biology 202
2004 First Web Paper
On Serendip

Autism is a neurological disorder that is interesting, in part, because of its potential to shed light on how we perceive and understand the world around us, and how we are able to relate to other human beings, by demonstrating what happens when one is unable to relate with others, and has trouble with perception and understanding. The abilities and complexity of the human brain can be seen most clearly when the brain is damaged and vital abilities have been lost. It is often only when one sees the debilitation caused by the loss of an ability that one can see the importance of that ability, and fully understand it.

Autism is characterized by problems in three specific areas: communication, imagination, and socialization.(5) Autistics generally have very poor verbal skills, and can be so unresponsive to speech and noise in general that they are sometimes mistakenly thought to be deaf.(7)(2) Autistics also have trouble understanding the meanings of intonations in a sentence, and have difficulty speaking with the proper intonations themselves. Autistic children often don't appear to engage in imaginative play. They tend to be very socially withdrawn, and unresponsive to human contact as children.(1)

There are other, less general characteristic symptoms. Autistics have trouble making eye contact,(7)(2)(1) and show an aversion to physical affection (such as hugging).(1)(2) There are often motor problems that accompany autism, such as a lack of coordination.(4) Autistics often show an obsession with order and a resistance to change,7 and a tendency to focus on parts of objects instead of the entire object.(5)

Quite a bit is known, then, about the outwardly observable characteristics of autism. To describe all of its observed characteristics in detail would take several pages at least. Autism is, though, a disorder that can unfortunately only be defined by outwardly observable behaviour. Its wide range of symptoms are classed together as one disorder simply because they are seen together often, too often for there not to be some link between them. It is believed that there is a common neurological problem (or even a group of related neurological problems) that is at the core of autism. However, one reason why autism is still something of a mystery and remains surrounded by controversy, is that after decades of research its biological basis is still not known for sure. One possibility is that damage to the amygdala is linked to autism. However, only about 50% of autistics show damage to the amygdala in MRI scans, so other structures are evidently involved as well.(4)

It is known, though, that autism does have an entirely biological basis.(4) Although it was thought for many years that autism was a psychological disorder, it is now known that autism is caused by a combination of genetic and environmental factors.(2) And although the specifics of its biological basis are not known, the neurological damage that lies behind autism creates specific cognitive defects that in turn cause the outward symptoms of autism. Two theories about such cognitive defects are the theory of mind hypothesis, and the theory of central coherence.

A theory of mind allows one to make deductions about what another person might be thinking based on his or her outward behaviour. It allows people to attribute separate beliefs and mental states to another person, and to link these mental states with outward behaviour. A hypothesis was put forth by Baron-Cohen et al in 1985 claiming that autistics lack a theory of mind.(3)

This claim was based on an experiment first done in 1985, where autistic children were given what is called a "false-belief" test. The test went roughly as follows. A girl named Sally hides a marble in a basket, and then leaves the room, so that she can no longer see the basket. Her friend Anne then takes the marble out of the first basket and puts it in a second basket. The question is: when Sally comes back to the room and looks for her marble, where will she look?

In order to correctly reply that Sally will look in the first basket, the subject has to be able to grasp the concept that Sally does not know everything that the subject knows, and therefore believes that her marble is still where she left it. In order to attribute such a false belief to another person, the subject would need to have a theory of mind. Only 20% of the autistic children tested were able to answer the question correctly. The other 80% replied that Sally would look for her marble in the second box. Also, when the 20% that were able to answer the question correctly were given more advanced tests to further test their theory of mind, the majority of them failed.

It has been generally accepted since then that one of the major cognitive deficits in autism is the lack of a theory of mind. However, although the majority of autistics failed the more advanced tests, not all failed. And this combined with the fact that 20% were able to pass a simple false-belief test shows that not all autistics completely lack a theory of mind. This would imply that there are other cognitive defects that contribute to autism, since most autistics who pass false-belief tests are still undoubtedly autistic (although they are generally high-functioning autistics). The fact that much autistic behaviour has no obvious relation to the theory of mind further supports this.(5) Other theories have therefore been put forward, one of which is autistics have weak central coherence.(5)

Central coherence is, in colloquial terms, the ability to see the big picture instead of getting lost in details. It is the ability to read a story and then be able to remember the gist of the story afterwards, even if individual details are lost. The theory put forward by Happé claims that autistics, although they have this ability to a certain degree, still have trouble with central coherence. Several experiments seem to support this claim, but simple observations of autistics support it as well: one widely observed characteristic of autistics is that they have a tendency to focus on the parts of an object over the whole.(5)

One experiment carried out by Happé tested the ability of autistic children to judge the meaning of a word based on the context of the sentence. For example, they were made to read outloud the sentences "There was a big tear in her eye", and "In her dress there was a big tear", to see if they would be able to judge which pronunciation of the word "tear" was appropriate for which sentence. In general it was found that they had difficulty with such judgements. They had a tendency to simply use the more common form of the word, regardless of the context. Another experiment showed that autistics show a remarkable ability for spotting "embedded figures" within an image, which also supports this theory.(5)

The theory of mind and central coherence are not aspects of the human brain that one would even necessarily think about, under normal circumstances. Most people don't think twice about their ability to read a book and understand it, somehow understanding both each individual word and the complex ideas that the words combine to form. Most people don't wonder about their ability to look into a person's eyes and know what that person is feeling. Both tasks are astounding. And yet it is human nature not to notice our own everyday abilities, no matter how astounding they are, simply because they are so common. It is often only when we lose an ability or learn about people who lack it that we take notice of our abilities, and the miracle that is the human brain. Autism has shown the effect when something so basic and necessary as the ability to relate to other human beings is lost from damage to the brain. The sheer isolation of autism is described well by an autistic woman named Donna Williams, in her autobiography,

Staring into nothingness since time began
There and yet not there she stood.
In a world of dreams, shadows, and fantasy,
Nothing more complex than color and indiscernible sound.
With the look of an angel no doubt,
But also without the ability to love or
Feel anything more complex than the sensation of cat's fur
Against her face.(8)

References

1) Autism Resources maintained by John Wobus. (accessed February 15, 2004)

2) Autism Society of America (accessed February 17, 2004)

3) Baron-Cohen, S., Leslie, A.M. and Frith, U. (1985) "Does the autistic child have a 'theory of mind'?" Cognition, 21, 37-46

4) Frith, Uta and Hill, Elisabeth. (2003) "New techniques yield insights on autism". (accessed February 18, 2004)

5) Happé, Francesca. (1997) "Autism: Understanding the mind, fitting together the pieces" (accessed February 17, 2004)

6) Rimland, Bernard. (1997) "Genetics, Autism, and Priorities". Autism Research Review International, Vol. 11, No. 2, page 3.(accessed February 17, 2004)

7) Sterling, Lisa. (2002) "Autism and Theory of Mind" (accessed February 16, 2004)

8) Williams, Donna. (1992) Nobody Nowhere, New York, New York: Avon Books.


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