Wednesday, November 9, 2011 - 0 comments

Autism : 3. Defect in Frontal Lobes (2)

by : Uta Frith

In the second year of life, a particularly dramatic manifestation of the critical component can be seen in normal children: the emergence of pretense, or the ability to engage in fantasy and pretend play. Autistic children cannot understand pretense and do not pretend  when they are playing. The difference can be seen in such a typical nursery game as “feeding” a teddy bear or a doll with an empty spoon. The normal child goes through the appropriate motions of feeding and accompanies the action with appropriate slurping noises. The autistic child merely twiddles or flicks the spoon repetitively. It is precisely the absence of early and simple  communicative behaviors, such as shared attention and make-believe play, that often creates the first nagging doubts in the minds of the parents about the development of their child. They rightly feel that they cannot engage the child in the emotional to-and-fro of ordinary life.

UNUSUAL BEHAVIOR is often displayed
by autistic individuals. Autistic
children, for example, tend to fixate
on making toys and other objects spin
and to play repetitively.
My colleague Alan M. Leslie devised a theoretical model of the cognitive mechanisms underlying the key abilities of shared attention and pretense. He postulates an innate mechanism whose function is to form and use what we might call second-order representations. The world around us consists not only of visible bodies and events, captured by first-order representations, but also of invisible minds and mental events, which require second-order representation. Both types of representation have to be kept in mind and kept separate from each other.

Second-order representations serve to make sense of otherwise contradictory or incongruous information. Suppose a normal child, Beth, sees her mother holding a banana in such a way as to be pretending that it is a telephone. Beth has in mind facts about bananas and facts about telephones—first-order representations.  evertheless, Beth is not the least bit confused and will not start eating telephones or talking to bananas. Confusion is avoided because Beth computes from the concept of pretending (a second-order representation) that her mother is engaging simultaneously in an imaginary activity and a real one.

As Leslie describes the mental process, pretending should be understood as computing a three-term relation between an actual situation, an imaginary situation and an agent who does the pretending. The imaginary situation is then not treated as the real situation. Believing can be understood in the same way as pretending. This insight enabled us to predict that autistic children would not be able to understand that someone can have a mistaken belief about the world.

Together with our colleague Simon Baron-Cohen, we tested this prediction by adapting an experiment  originally devised by two Austrian developmental psychologists, Heinz Wimmer and Josef Perner. The test has become known as the Sally-Anne task. Sally and Anne are playing together. Sally has a marble that she puts in a basket before leaving the room. While she is out, Anne moves the marble to a box. When Sally returns, wanting to retrieve the marble, she of course looks in the basket. If this scenario is presented as, say, a puppet show to normal children who are four years of age or more, they understand that Sally will look in the basket even though they know the marble is not there. In other words, they can represent Sally’s erroneous belief as well as the true state of things. Yet in our test, 16 of 20 autistic children with a mean mental age of nine failed the task—answering that Sally would look in the box—in spite of being able to answer correctly a variety of other questions relating to the facts of the episode. They could not conceptualize the possibility that Sally believed something that was not true.

Many comparable experiments have been carried out in other laboratories, largely confirming our prediction:  utistic children are specifically impaired in their understanding of mental states. They appear to lack the innate component underlying this ability. This component, when it works normally, has the most far-reaching consequences for higher-order conscious processes. It underpins the special feature of the human mind: the ability to reflect on itself. Thus, the triad of impairments in autism—in communication, imagination and socialization—is explained by the failure of a single cognitive mechanism. In everyday life, even very able autistic individuals find it hard to keep in mind simultaneously a reality and the fact that someone else may hold a misconception of that reality.

The automatic ability of normal people to judge mental states enables us to be, in a sense, mind readers. With sufficient experience we can form and use a theory of mind that allows us to speculate about psychological motives for our behavior and to manipulate other people’s opinions, beliefs and attitudes. Autistic individuals lack the automatic ability to represent beliefs, and therefore they also lack a theory of mind. They cannot understand how behavior is caused by mental states or how beliefs and attitudes can be manipulated. Hence, they find it difficult to understand deception. The psychological undercurrents of real life as well as literature—in short, all that gives spice to social relations—for them remain a closed book. “People talk to each other with their eyes,” said one observant autistic youth. “What is it that they are saying?”

Next : Theory of Mind
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