Theory of mind impairment in autism

The theory of mind impairment in autism is the inability to ascribe mental states to oneself and others. Autism is a neurodevelopmental disorders that impairs social interaction and communication, and causes restricted and repetitive behavior, all starting before a child is three years old. This set of signs distinguishes autism from milder autism spectrum disorders (ASD) such as Asperger syndrome. Autistic children find even the immediate social environment unpredictable and incomprehensible and are often said in some sense to ‘treat people and objects alike’. Many psychological research suggests that children with autism do not employ a theory of mind.

Study by Baron-Cohen, Leslie and Frith

In 1985, Simon Baron-Cohen, Alan M. Leslie and Uta Frith published a psychological research which suggested that children with autism do not employ a theory of mind.

Method

Three groups of children - 20 autistic children, 14 Down's syndrome children and 27 'normal' children - were used as participants for the experiment. Their mean chronological age (CA) and mean verbal mental age (vMA) were:

Type of participants	Mean Chronological Age	Mean Verbal Mental age
Autistic children	11;11 (11 years, 11 months)	5;5 (5 years, 5 months)
Down's syndrome	10;11 (10 years, 11 months)	2;11 (2 years, 11 months)
'Normal' children	4;5 (4 years, 5 months)	not tested, assumed age appropriate

It is important to note that the mean vMA of the autistic children (5;5) were higher than the mean vMA of the Down’s syndrome children (2;11) and the normal children (assumed 4;5). The autistic group had an advantage in terms of age (experience) and verbal ability. If success on the task depends on these factors, then this group should perform as well as or better than the other groups.

The 61 children were tested one at a time. They were seated behind a desk opposite the experimenter. On the desk, there were two dolls - Sally and Anne. Sally had a basket in front of her, and Anne had a box. The two dolls were introduced to the children.

After introducing the dolls, the child's ability to name those dolls was tested (the Naming Question).

After this, Sally takes a marble and hides it in her basket. She then leaves the room and goes for a walk. When Sally is away, and therefore unknown to her, Anne takes the marble out of Sally's basket and puts it in her own box. Sally returns and the child is asked the key question: 'Where will Sally look for her marble?' (the Belief Question).

Two control questions are then asked - the Reality Question and the Memory Question.

The Reality question is "Where is the marble really?". This is to make sure the child had paid attention to the transfer of the marble from the basket to the box.

The Memory question is "Where was the marble in the beginning?". This is designed to make sure the child had not forgotten where Sally had left her marble.

Every child is tested twice and during the second time, a new location for the marble is introduced. The new location is the experimenter's pocket.

For the children to succeed in this task they have pass the 'Belief Question'. The children have to show that Sally has her own beliefs which may not match up with how things really are. The correct response to the 'Belief Question' is to indicate Sally's basket. This will show that the child knows that Sally believes the marble is in her basket. The incorrect response is to point to Anne's box (Sally doesn't know that Anne hid her marble in the box).

Results

The percentage of correct answers to each of the four questions asked were:

Questions	Autistic children	Down's Syndrome children	'Normal' children
Naming	100	100	100
Reality	100	100	100
Memory	100	100	100
Belief	20	86	85

The result was that 'naming', 'reality', and 'memory' questions were answered correctly by all the children. However, the results were different for the Belief Question. The results for Down’s Syndrome and normal subjects were quite similar. 23 out of 27 normal children, and 12 out of 14 Down’s Syndrome children passed the Belief Question on both trials (85% and 86% respectively). By contrast, only 4 of the 20 autistic children (20%) passed the Belief Question on both trials. The 16 autistic children who gave the wrong response on both trials pointed to where the marble really was rather than to where Sally must believe it to be. The results seem to support the notion that autistic children may have under-developed 'theory of mind'.

Discussion

The belief question was answered correctly by only 20% of the autistic children. This suggests that the autistic children are impaired in or lack a theory of mind. Autistic children are known not to engage themselves in pretend play, so the use of dolls rather than real people could have been a mistake. In 1988, the study was replicated by Alan M. Leslie and Uta Frith using people rather than dolls, and the results followed the same pattern as the original experiment.Leslie AM, Frith U (1988). "Autistic children's understanding of seeing, knowing and believing" (PDF). British Journal of Developmantal Psychology. 6. The British Psychological Society: 315–324. Retrieved 2008-02-16.</ref>

This finding is very useful, as looking for the absence of a theory of mind is a clear indicator in diagnosing autism as well as suggesting an appropriate treatment.