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871.
872.
ABSTRACT

This article compared alcoholics and healthy controls on the Buschke Selective Reminding Task. Alcoholics demonstrated deficits in memory and learning when compared to healthy controls, even when controlling for age. Examination of the alcoholic sample initially showed that age predicted memory deficits; however, age was no longer a significant predictor once the number of years of heavy drinking was entered into the regression equation. Findings suggest a direct link or mechanism of action between alcohol use and memory impairments, above and beyond effects of age or education.  相似文献   
873.
ABSTRACT

Objective: Few studies have addressed whether the metabolic syndrome (MetS) and its individual components are associated with cognitive function in middle-aged and older populations, as well as whether specific areas of cognition are more affected than others. We examined the cross-sectional association between MetS and six areas of cognitive function in healthy cognitively intact adults without diabetes (n?=?853, mean age 61 years) randomized in two intervention trials. Methods: The National Cholesterol Education Program (NCEP) criteria were used to identify subjects with MetS. Cognitive function was assessed with a neuropsychological battery. A principal components analysis was used to extract five uncorrelated factors interpreted to represent five areas of cognition, and a measure of global cognition was calculated. Results: MetS was weakly but non-significantly associated with lower verbal learning (β?=??.14 [SE(β)?=?0.09], p?=?.15). As the number of MetS criteria increased, scores on global cognition (p trend?=?.01), verbal learning (p trend?=?.06) and semantic memory (p trend?=?.04) decreased. Hypertension was the only MetS risk factor that was independently correlated with lower verbal learning (β?=??.17 [SE(β) =?0.08], p?=?.04), semantic memory (β?=??.26 [SE(β)?=?0.08], p?=?.001) and global cognition (β?=??.15 [SE(β)?=?0.07], p?=?.04). Conclusion: This study adds to the evidence of an association between MetS and lower cognitive function among healthy middle-aged and older adults without CVD and diabetes, as well as confirms the correlation between hypertension and lower cognition.  相似文献   
874.
ABSTRACT

The Attentional Blink (AB) refers to a decrease in the chance of detecting a second target in a rapid sequence of items if it occurs within approximately 500 ms of a first target. In this study the efficiency of establishing and switching cognitive set for older adults (mean age 71.62 years) relative to young adults (mean age 21.33 years) was investigated. Three increasingly complex conditions of the AB paradigm were employed, each of which required participants to identify a coloured square (T1) and a letter (T2) within a stream of distracters. Accuracy of identification of T2 decreased for both young and older adults as complexity increased. In Condition 1, selection criteria for both targets were fully specified, while T1 acted as a direct cue to the selection criteria for T2 in Condition 2. Older participants took longer to establish cognitive set in this condition. Condition 3 contained an added requirement to activate a pre-determined rule for T2 selection. The basic requirement to establish cognitive set ‘online’, however, seemed to disguise any additional potential problems associated with the additional load required for Condition 3 for older adults. Younger adults were cognitively slowed in Condition 3 relative to Condition 2, suggesting that it is the need to use an internally generated cue to switch cognitive set that requires extra time for them. The significantly larger AB demonstrated by the older participants indicated an impaired ability to rapidly establish cognitive set. The findings are discussed in light of the current literature on cognitive aging, the AB and task switching.  相似文献   
875.
ABSTRACT

Social support has a positive influence on cognitive functioning and buffers cognitive decline in older adults. This study examined the relations between social support and executive functioning in middle-aged adults. A community-based sample of African Americans completed the Interpersonal Support Evaluation List, a measure of functions of social support, and two measures of executive functioning, the Stroop Color and Word Test and the Wisconsin Card Sorting Test (WCST). Hierarchical regression analyses were used to explore the hypothesis that different facets of perceived social support influence performance on measures of executive functioning. After controlling for age, gender, and education, social support facets including belonging support, selfesteem support, appraisal support, and tangible support were significant predictors of Stroop performance. In addition, tangible support significantly predicted WCST performance. These findings add to previous literature on social support and cognition; however, findings for middle-aged adults are unique and suggest that social support has a positive influence on some executive functions in African Americans prior to old age.  相似文献   
876.
ABSTRACT

An increase in Stroop effects with age can be interpreted as reflecting age-related reductions in selective attention, cognitive slowing, or color-vision. In the present study, 88 younger adults performed a Stroop test with two color-sets, saturated and desaturated, to simulate an age-related decrease in color perception. This color manipulation with younger adults was sufficient to lead to an increase in Stroop effects that mimics age-effects. We conclude that age-related changes in color perception can contribute to the differences in Stroop effects observed in aging. Finally, we suggest that the clinical applications of Stroop take this factor into account.  相似文献   
877.
ABSTRACT

The purpose of this study was to examine daytime performance in older adults fulfilling the diagnostic criteria for DSM-IV Insomnia, using a comprehensive battery of neuropsychological tests, and to compare these objective findings with measures of self-reported cognitive functioning. A total of 121 participants (69% women) with a mean age of 64.0 were part of a thorough neuropsychological examination at a University-based neuropsychological clinic in Western Norway. Twenty-five percent of the participants fulfilled the diagnostic criteria for insomnia. In sum, the insomnia patients were not different from the good sleepers on any neuropsychological test measure, and none of the results on the performance measures were associated with the sleep-related daytime complaints. However, the insomniacs did rate their subjective memory performance as significantly worse than the good sleepers, and they also reported more depressive symptoms. We conclude that DSM-IV defined insomnia was not associated with any performance based measure; only with self-reported symptoms.  相似文献   
878.
ABSTRACT

Sex differences in patterns of cognitive test performance have been attributed to factors, such as sex hormones or sexual dimorphisms in brain structure, that change with normal aging. The current study examined sex differences in patterns of cognitive test performance in healthy elderly individuals. Cognitive test scores of 957 men and women (age 67–89), matched for overall level of cognitive test performance, age, education, and depression scale score, were compared. Men and women were indistinguishable on tests of auditory divided attention, category fluency, and executive functioning. In contrast, women performed better than men on tests of psychomotor speed and verbal learning and memory, whereas men outperformed women on tests of visuoconstruction and visual perception. Our finding that the pattern of sex differences in cognition observed in young adults is observed in old age has implications for future studies of both healthy elderly individuals and of those with cognitive disorders.  相似文献   
879.
Whether unconscious stimuli can modulate the preparation of a cognitive task is still controversial. Using a backward masking paradigm, we investigated whether the modulation could be observed even if the prime was made unconscious in 100% of the trials. In two behavioral experiments, subjects were instructed to initiate a phonological or semantic task on an upcoming word, following an explicit instruction and an unconscious prime. When the SOA between prime and instruction was sufficiently long (84 ms), primes congruent with the task set instruction led to speedier responses than incongruent primes. In the other condition (36 ms), no task set priming was observed. Repetition priming had the opposite tendency, suggesting the observed task set facilitation cannot be ascribed solely to perceptual repetition priming. Our results therefore confirm that unconscious information can modulate cognitive control for currently active task sets, providing sufficient time is available before the conscious decision.  相似文献   
880.
The resource-based model of self-regulation provides a pessimistic view of self-regulation that people are destined to lose their self-control after having engaged in any act of self-regulation because these acts deplete the limited resource that people need for successful self-regulation. The cognitive control theory, however, offers an alternative explanation and suggests that the depletion effect reflects switch costs between different cognitive control processes recruited to deal with demanding tasks. This account implies that the depletion effect will not occur once people have had the opportunity to adapt to the self-regulatory task initially engaged in. Consistent with this idea, the present study showed that engaging in a demanding task led to performance deficits on a subsequent self-regulatory task (i.e. the depletion effect) only when the initial demanding task was relatively short but not when it was long enough for participants to adapt. Our results were unrelated to self-efficacy, mood, and motivation.  相似文献   
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