Biomedical subjects

Michael Siegal

Publications and source records attributed to Michael Siegal.

3 recordsLinked to original sources

PubMed2003

Language and auditory processing in autism.

Autism is characterized by varying degrees of disorders in language, communication and imagination. What are the prospects for making sense of this heterogeneous condition? Advances in identifying phenotypes in relation to subgroups within autism, based on disproportionate language impairment, have been recently reported by Tager-Flusberg and Joseph. The symptom severity of these subgroups requires investigation for underlying deficits, such as in auditory processing. Other recent reports support the view that a deficit in auditory processing might be a key factor in autism.

Journal Article↗

PubMed2002

Neural systems involved in "theory of mind".

What is the nature of our ability to understand and reason about the beliefs of others--the possession of a "theory of mind", or ToM? Here, we review findings from imaging and lesion studies indicating that ToM reasoning is supported by a widely distributed neural system. Some functional components of this system, such as language-related regions of the left hemisphere, the frontal lobes and the right temporal parietal cortex, are not solely dedicated to the computation of mental states. However, the system also includes a core, domain-specific component that is centred on the amygdala circuitry. We provide a framework in which impairments of ToM can be viewed in terms of abnormalities of the core system, the failure of a co-opted system that is necessary for performance on a particular set of tasks, or the absence of an experiential trigger for the emergence of ToM.

Amygdala↗

PubMedDate not supplied

Signposts to development: theory of mind in deaf children.

Possession of a "theory of mind" (ToM)--as demonstrated by an understanding of the false beliefs of others--is fundamental in children's cognitive development. A key question for debate concerns the effect of language input on ToM. In this respect, comparisons of deaf native-signing children who are raised by deaf signing parents with deaf late-signing children who are raised by hearing parents provide a critical test. This article reports on two studies (N = 100 and N = 39) using "thought picture" measures of ToM that minimize verbal task-performance requirements. These studies demonstrated that even when factors such as syntax ability, mental age in spatial ability, and executive functioning were considered, deaf late signers still showed deficits in ToM understanding relative to deaf native signers or hearing controls. Even though the native signers were significantly younger than a sample of late signers matched for spatial mental age and scores on a test of receptive sign language ability, native signers outperformed late signers on pictorial ToM tasks. The results are discussed in terms of access to conversation and extralinguistic influences on development such as the presence of sibling relationships, and suggest that the expression of a ToM is the end result of social understanding mediated by early conversational experience.

Child↗