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Sarah E MacPherson

Publications and source records attributed to Sarah E MacPherson.

5 recordsLinked to original sources
PubMed2006

Age-related differences in the ability to perceive sad facial expressions.

BACKGROUND AND AIMS: Research has shown that the ability to label negative emotions displayed by facial expressions declines with age. Such studies, however, have tended to adopt the Ekman and Friesen (1976) Caucasian faces as their emotional stimuli. The purpose of the current study was to examine whether the age differences in identifying negative emotions are also found using the more recent Japanese and Caucasian Facial Expressions of Emotion (JACFEE). METHODS: In Experiment 1, 29 younger and 29 older individuals performed a verbal labeling emotion identification task (happy, sad, angry, frightened, disgusted, surprised, contemptuous). The ability to identify each emotion as a function of ethnicity across the age groups was examined. In order to reduce the verbal decision-making load on the task, a second experiment was conducted in which 60 younger and 60 older participants performed an emotion-matching task (sad, angry, contemptuous). RESULTS: In Experiment 1, older adults showed a significant decrement in the ability to recognize sad faces compared with younger adults, but no age x face ethnicity interaction was found. In Experiment 2, age differences were found when making same/different judgments regarding two sad faces or a sad and a contemptuous face. CONCLUSIONS: Results suggest that aging has an impact upon perceiving sad facial expressions, that this effect is not mediated by own-race versus other-race faces, and that age effects are not attributable to differences in verbal decision-making.

Adult↗
PubMed2004

The role of semantic knowledge on the cognitive estimation task--evidence from Alzheimer's disease and healthy adult aging.

The current study investigated the role of semantic knowledge on the Cognitive Estimation Task (CET). In an initial experiment, the CET performance of 21 patients with frontal lobe lesions was compared with 21 healthy controls. The CET was found to be sensitive to the effects of frontal lobe lesions. In Experiment 2, 175 participants aged between 18 and 87 years performed the CET to examine the effects of healthy adult aging on the task. No significant age effects were evident. In Experiment 3, 27 patients with Alzheimer's disease (AD) were compared with 27 healthy controls on the CET. AD patients produced significantly more extreme cognitive estimates than the controls. A significant correlation was found between CET performance and performance on the General Knowledge of the World Task, a task intended to assess semantic knowledge. The hypothesis is put forward that healthy older adults are able to use their intact semantic knowledge to compensate for problem-solving deficits when generating cognitive estimates. In contrast, owing to degradation in semantic abilities, AD patients are unable to benefit from semantic knowledge and instead tend to produce bizarre cognitive estimates.

Adolescent↗
PubMed2002

Concurrent performance of two memory tasks: evidence for domain-specific working memory systems.

Previous studies of dual-task coordination in working memory have shown a lack of dual-task interference when a verbal memory task is combined with concurrent perceptuomotor tracking. Two experiments are reported in which participants were required to perform pairwise combinations of (1) a verbal memory task, a visual memory task, and perceptuomotor tracking (Experiment 1), and (2) pairwise combinations of the two memory tasks and articulatory suppression (Experiment 2). Tracking resulted in no disruption of the verbal memory preload over and above the impact of a delay in recall and showed only minimal disruption of the retention of the visual memory load. Performing an ongoing verbal memory task had virtually no impact on retention of a visual memory preload or vice versa, indicating that performing two demanding memory tasks results in little mutual interference. Experiment 2 also showed minimal disruption when the two memory tasks were combined, although verbal memory (but not visual memory) was clearly disrupted by articulatory suppression interpolated between presentation and recall. These data suggest that a multiple-component working memory model provides a better account for performance in concurrent immediate memory tasks than do theories that assume a single processing and storage system or a limited-capacity attentional system coupled with activated memory traces.

Adult↗
PubMed2002

Age, executive function, and social decision making: a dorsolateral prefrontal theory of cognitive aging.

Current neuropsychological models propose that some age-related cognitive changes are due to frontal-lobe deterioration. However, these models have not considered the possible subdivision of the frontal lobes into the dorsolateral and ventromedial regions. This study assessed the age effects on 3 tasks of executive function and working memory, tasks dependent on dorsolateral prefrontal dysfunction; and 3 tasks of emotion and social decision making, tasks dependent on ventromedial prefrontal dysfunction. Age-related differences in performance were found on all tasks dependent on dorsolateral prefrontal dysfunction. In contrast, age-related differences were not found on the majority of the tasks dependent on ventromedial prefrontal dysfunction. The results support a specific dorsolateral prefrontal theory of cognitive changes with age, rather than a global decline in frontal-lobe function.

Adult↗