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Biomedical subjects

A M Leslie

Publications and source records attributed to A M Leslie.

12 recordsLinked to original sources
PubMed1998

Solving belief problems: toward a task analysis.

Solving belief problems develops as a skill in normal children during the preschool years. To understand this process of development, it is necessary to provide an analysis of the tasks used to test preschool 'theory of mind' skills. This analysis should allow us to relate the structure of a given task to the underlying cognitive mechanisms that the task engages. In two experiments, we find that 3-year-old children show a pattern of success and failure on belief tasks that is not consistent with 'conceptual deficit' accounts. Young children possess the concept, BELIEF, but have certain characteristic difficulties with correctly calculating the contents of beliefs. In childhood autism, by contrast, the mechanisms that in normal development bestow conceptual competence in this domain are impaired. In the first experiment, parallel task structures are used to show that 3-year-olds are no better at predicting behavior from a partially true belief than they are at predicting behavior from an entirely false belief. We develop specific proposals about task structural factors that either facilitate or hinder success in belief-content calculation. These proposals are supported in a second experiment. We compare two false-belief tasks, one of which has helpful structural factors, the other of which has hampering factors, with a third task which exemplifies a hampering task structure but without any theory of mind content. We compare 3- and 4-year-olds' patterns of performance with that of autistic children. Each of the three groups shows a distinct performance profile across the three tasks, as predicted for each case by our model. Innate attentional mechanisms provide the conceptual foundations for 'theory of mind' but must be supplemented by a robust executive process that allows false beliefs to achieve 'conceptual pop-out.' Our approach has general implications for the study of conceptual development.

Autistic Disorder↗
PubMed1992

Domain specificity in conceptual development: neuropsychological evidence from autism.

To understand some aspects of conceptual development it is necessary to take cognitive architecture into account. For this purpose, the study of normal development is often not sufficient. Fortunately, one can also study neurodevelopmental disorders. For example, autistic children have severe difficulties developing certain kinds of concepts but not others. We find that whereas autistic children perform very poorly on tests of the concept, believes, they are at or near ceiling on comparable tasks that test understanding of pictorial representation. A similar pattern was found in a second study which looked at understanding of a false map or diagram: normal 4-year-olds showed a marked advantage in understanding a false belief over a false map, while the autistic subjects performed better on the map. These findings suggest that the concept, believes, develops as a domain-specific notion that is not equatable with "having a picture (map or diagram) in the head." This result supports the existence of a specialized cognitive mechanism, which subserves the development of folk psychological notions, and which is dissociably damaged in autism. We extend these ideas to outline a new model of the development of false belief performance.

Autistic Disorder↗
PubMed1991

The cognitive basis of a biological disorder: autism.

This article summarizes recent evidence indicating that individuals suffering from autism have a specific problem in understanding intentions and beliefs. We propose that this problem arises because they are incapable of forming a special kind of mental representation. A single cognitive deficit defines what is common to all autistic individuals. In contrast there is a wide range of proposals for the biological origins of the disorder.

Autistic Disorder↗
PubMed1990

Prospects for a cognitive neuropsychology of autism: Hobson's choice.

Leslie (1987b) proposed a new, metarepresentational model for the cognition of pretense. This model identified a cognitive component necessary for the normal development of a "theory of mind." In this article, the relation of the child's early affective sensitivities to this component is considered. Early affective sensitivities seem to be cognitively distinct from the metarepresentational component. Childhood autism provides an interesting opportunity to study this problem. Three theoretical possibilities for the pathogenesis of this condition are presented: (a) a basic affective disorder as proposed by Hobson (this issue, p. 114), (b) a basic affective disorder and a basic cognitive disorder jointly, and (c) a basic cognitive disorder. There is little evidence for Option a, and a growing body of evidence supports Option c. Option b is sidelined for the time being on grounds of parsimony. Leslie's original theoretical proposals are revised, and some resulting implications are presented for the future investigation of the cognitive neuropsychology of autism.

Autistic Disorder↗
PubMed1989

Exploration of the autistic child's theory of mind: knowledge, belief, and communication.

26 autistic children with mental ages of 3-13 years were tested on 3 tasks that are within the capability of 3- or 4-year-old normal children. The first task tested understanding of a mistaken belief. Children were shown a typical box of a certain brand of sweets, and they all thought that it contained that kind of sweet. To their surprise, however, the box contained something else. Yet, only 4 out of the 26 autistic children were able to anticipate that another child in the same situation would make the same mistake. In contrast, all but 1 of 12 children with specific language impairment, matched for mental age, understood that others would be as misled as they had been themselves. The autistic children were also tested for their ability to infer knowledge about the content of a container from having or not having looked inside. All 4 children who had passed the belief task and an additional 4 performed perfectly, but most failed. The third task assessed children's pragmatic ability to adjust their answers to provide new rather than repeat old information. Here, too, most autistic children seemed unable to reliably make the correct adjustment. These results confirm the hypothesis that autistic children have profound difficulty in taking account of mental states.

Adolescent↗
PubMed1984

Spatiotemporal continuity and the perception of causality in infants.

Infant perception of a Michottean launching event in which one object causes another to move through collision is examined in a series of habituation-test experiments. A number of hypotheses concerning how infants aged around 30 weeks might perceive and encode launching and its noncausal variants are identified and tested. The results of the first experiment indicate that infants can perceive direct launching as an event with internal structure, that is, as composed of two temporally ordered movements. The nature of the encoding by the infants is perceptual and not specifically motor-based. The second experiment makes it seem unlikely that the infants encode independent spatial and temporal features (for example, contact and successivity), while the third experiment suggests a spatiotemporal continuity gradient. Some implications for the origins of causality are discussed.

Concept Formation↗
PubMed1982

The perception of causality in infants.

The problem of the origins of the perception of causality in infancy has received relatively little attention in the literature despite its obvious importance. Two experiments with infants 4 1/2 and 8 months old are reported which seek to investigate sensitivity to spatiotemporal continuity in simple causal events with a differential dishabituation-of-looking technique. In the first experiment inanimate events of the familiar 'billiard-ball launching' type were used, while in the second animate events involving a hand/object pick-up were presented. The results suggest that both age groups of infants were sensitive to certain changes in spatiotemporal continuity in both types of event, although in the case of the inanimate stimuli the younger infants reacted less positively. It is suggested that infants in the first year of life are sensitive to certain spatiotemporal event configurations and that this sensitivity could be regarded as at least a required component of a perception of causality.

Age Factors↗
PubMedDate not supplied

Pretending and believing: issues in the theory of ToMM.

Commonsense notions of psychological causality emerge early and spontaneously in the child. What implications does this have for our understanding of the mind/brain and its development? In the light of available evidence, the child's "theory of mind" is plausibly the result of the growth and functioning of a specialized mechanism (ToMM) that produces domain-specific learning. The failure of early spontaneous development of "theory of mind" in childhood autism can be understood in terms of an impairment in the growth and functioning of this mechanism. ToMM constructs agent-centered descriptions of situations or "metarepresentations". Agent-centered descriptions place agents in relation to information. By relating behavior to the attitudes agents take to the truth of propositions, ToMM makes possible a commonsense causal interpretation of agents' behavior as the result of circumstances that are imaginary rather than physical. Two early attitude concepts, pretends and believes, are discussed in the light of some current findings.

Child, Preschool↗