Biomedical subjects

L Clarkson-Smith

Publications and source records attributed to L Clarkson-Smith.

4 recordsLinked to original sources

PubMed1990

Structural equation models of relationships between exercise and cognitive abilities.

Data were obtained from 300 men and women aged 55 to 91. Separate structural equation models of relationships between physical exercise and 3 cognitive performance variables--reaction time, working memory, and reasoning--fit the data well. Other variables in the models were age, health, education, and morale. Age and exercise affected each performance variable directly; education had a direct effect on reasoning only. There were also indirect effects of age and health on performance variables, mediated through exercise. The main hypothesis of the study, that exercise contributes to performance, was supported. A large decrease in model fit resulted when the path from exercise to each performance variable was deleted. Hypotheses that age-related deficits are primarily accounted for by lack of exercise or by poor health were not supported.

Aged↗

PubMed1990

The game of bridge as an exercise in working memory and reasoning.

Fifty bridge players and 50 nonplayers, between the ages of 55 and 91, were given tests of working memory, reasoning, reaction time, and vocabulary. Data were analyzed using multivariate and univariate analyses of variance with age as a covariate. Results indicated that the players outperformed nonplayers in measures of working memory and reasoning, but not vocabulary and reaction time. Results were consistent with the hypothesis that bridge, which provides specific experience in working memory and reasoning, should enhance performance in tasks tapping these abilities and not enhance performance in unrelated abilities. Because the data were correlational, the rival hypothesis that bridge playing selects for individuals who perform better at working memory and reasoning tasks could not be rejected.

Aged↗

PubMed1989

Relationships between physical exercise and cognitive abilities in older adults.

We investigated relationships between physical exercise and the cognitive abilities of older adults. We hypothesized that the performance of vigorous exercisers would be superior to that of sedentary individuals on measures of reasoning, working memory, and reaction time. We gave a series of cognitive tasks to 62 older men and women who exercised vigorously and 62 sedentary men and women. Multivariate and univariate analyses of variance, with age and education as covariates, indicated that the performance of the exercisers was significantly better on measures of reasoning, working memory, and reaction time. Between-group differences persisted when vocabulary, on which the performance of exercisers was superior, was used as a third covariate. Subsequent analyses showed that neither self-rated health, medical conditions, nor medications contributed to the differences between exercise groups. Results suggest that the possible contribution of physical exercise to individual differences in cognition among older adults should be further investigated.

Adult↗

PubMed1983

Can age-related deficits in spatial memory be attenuated through the use of verbal coding?

In a sequential mental rotation task, women of three age groups (18-28, 50-60, and 70-80) viewed semi-abstract figures which were rotated in the picture plane. To investigate the effects of verbal mediation, each figure was presented under one of four labeling conditions. Errors increased as a function of age. Meaningful labels were beneficial in decreasing errors for the older subjects. Reaction time results generally replicated earlier studies, but there were indications that some women in the oldest group might have used strategies other than mental rotation. Results suggest that possible age related deficiencies in spatial abilities may be compensated for by greater use of verbal mediation.

Adolescent↗