PubMed Health⌕ Search

Biomedical subjects

J G Wishart

Publications and source records attributed to J G Wishart.

12 recordsLinked to original sources
PubMed1990

The effects of experience on attribution of a stereotyped personality to children with Down's syndrome.

A questionnaire in the form of a bipolar rating scale was constructed using 26 personality attributes drawn from the literature on personality of children with Down's syndrome (DS). This was administered to nine groups of adults with differing levels of experience and contact with children with DS. Adults who had frequent contact proved to be significantly less likely to rate the personality of children with DS as stereotypical than those with little contact. The implications of acceptance of the stereotype are discussed in relation to integration and to development of the mother-child relationship.

Adult↗
PubMed1990

Instability of performance on cognitive tests in infants and young children with Down's syndrome.

Stability of cognitive performance in assessment situations was investigated in a group of 18 children with Down's Syndrome (DS) aged 6 months to 4 years. Two widely used tests of early cognitive development were presented: the Mental Scale of the Bayley Scales of Infant Development and a series of Piagetian object concept tasks. Both sets of tasks were presented in the same testing session, with testing repeated one to two weeks later. Both qualitative and quantitative aspects of performance were recorded. Even when overall scores were similar, patterns of pass/fails were very different in the two testing sessions. Successes showed poor stability over sessions with fails often occurring by default, the result of a refusal to engage fully in a particular task. This pattern of results suggests: (1) that single-session testing may not adequately assess cognitive status in DS children; (2) that the relationship between performance and competence may be unstable in such children, and (3) that "slow development" theories may not adequately describe cognitive development in young children with DS.

Achievement↗
PubMed1987

Performance of young nonretarded children and children with Down syndrome on Piagetian infant search tasks.

Two groups of 3- to 5-year-old children, a nonretarded and a Down syndrome group, were tested six times over 2.5 months on three Piagetian infant search tasks. Two opposing trends in performance over sessions were evident: Scores of children in the Down syndrome group increased significantly whereas the performance of nonretarded subjects declined. The data suggest that cognitive ability of children with Down syndrome may be poorly measured by single-session testing; also, that in the absence of normative data from nonretarded children, caution is necessary in evaluating the performance of children with mental retardation on tests designed for and validated on younger, nonretarded subjects.

Attention↗
PubMed1986

The effects of step-by-step training on cognitive performance in infants with Down's syndrome.

A study of Morss (1984) suggested that the characteristically poor performance of Down's syndrome (DS) infants on object concept tasks could be enhanced by embedding the standard task within a short training sequence. This paper reports an attempt to replicate that study and to test for any carry-over of improved performance to subsequent testing sessions 2 and 6 weeks later. Ten DS subjects (mean age: 19 months) took part in the study. The search behaviour of almost all subjects improved, both in qualitative terms and in terms of the frequency of successful retrievals of the hidden object. Many also, however, showed evidence of a highly-specific form of 'switching out' of the testing sessions. The problems that this cognitive avoidance causes for establishing statistical criteria for attribution of success/failure on these tasks are discussed.

Attention↗
PubMed1986

Siblings as models in early infant learning.

4 groups of infants, 2 at 6 months and 2 at 12 months, were tested on the Stage IV-V and V-VI object concept tasks. All groups were then retested on the same tasks 1 week later. Retesting of the experimental groups was preceded by an all-correct demonstration of the 2 search tasks by the infant's preschool sibling; control groups were not exposed to any model prior to reassessment. No effect of exposure to the sibling model was initially found in either age group. If, however, infants' initial stage of development was taken into account, cognitive performance on the lower-level task did show a significant improvement after modeling. Overall, the results suggest that sibling modeling could possibly be an effective method of facilitating cognitive development in infancy, but that the success or failure of any modeling attempt may be stage- rather than age-dependent.

Child Development↗
PubMed1984

Modelling the stages of the identity theory of object-concept development in infancy.

A computational model is presented for the three stages of development of the object concept in infancy identified by Bower and Wishart in their research. The stages are described by sets of PROLOG clauses that interpret object structures representing the perceptual phenomena interpreted by the infants themselves. The infant's changes between developmental stages can be described by differences between the rules modelling each stage. Three experiments are presented and the behaviour of the PROLOG model is described for each stage of development. Motion, rest, and boundedness of objects constitute the theoretical underpinning of the running PROLOG model and are hypothesized as the invariant aspects of perception that explain the behaviour of the infant at each stage of development. A possible explanation for transitions between stages is offered and justified in part by the output of the model, which in turn is used to predict the behavioural outcome of an experiment.

Child Development↗
PubMed1983

A model of the development of the early infant object concept.

A computational model is proposed for the early stages of development of the object concept in infancy. Stages in development are represented as a sequence of grammars or rewrite rules that parse a set of perceptual phenomena. The infant's changes between developmental stages can be described by differences between the grammar rules that model each stage. The program replicates five studies by Bower et al on the development of the object concept and reaffirms the primacy of rest and motion parameters as explanatory invariants in early object-concept development.

Concept Formation↗
PubMed1978

Reaching in the dark.

Reaching for noise-making objects presented in darkness declines, then recovers, during infancy. The most probable explanation of this U-shaped function would seem to involve changes in reaching, changes in the perception of success, and changes in the body schema. There is no need to postulate any U-shaped change within the auditory system.

Age Factors↗