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991.
This article proposes and tests a formal cognitive model for the go/no-go discrimination task. In this task, the performer chooses whether to respond to stimuli and receives rewards for responding to certain stimuli and punishments for responding to others. Three cognitive models were evaluated on the basis of data from a longitudinal study involving 400 adolescents. The results show that a cue-dependent model presupposing that participants can differentiate between cues was the most accurate and parsimonious. This model has 3 parameters denoting the relative impact of rewards and punishments on evaluations, the rate that contingent payoffs are learned, and the consistency between learning and responding. Commission errors were associated with increased attention to rewards; omission errors were associated with increased attention to punishments. Both error types were associated with low choice consistency. The parameters were also shown to have external validity: Attention to rewards was associated with externalizing behavior problems on the Achenbach scale, and choice consistency was associated with low Welsh anxiety. The present model can thus potentially improve the sensitivity of the task to differences between clinical populations. 相似文献
992.
New structural and functional imaging methods continue to be developed at a rapid pace. In the last 25 years, advanced imaging
techniques have provided insights into how language is represented and processed in the brain and how it can be disrupted
by damage to, or dysfunction of, various parts of the brain. Imaging studies have also yielded new information regarding how
individuals recover language after stroke. We briefly review the strengths and weaknesses of the various radiological methods
currently used to study language and aphasia. 相似文献
993.
Factors predicting the use of technology: findings from the Center for Research and Education on Aging and Technology Enhancement (CREATE) 总被引:4,自引:0,他引:4
Czaja SJ Charness N Fisk AD Hertzog C Nair SN Rogers WA Sharit J 《Psychology and aging》2006,21(2):333-352
The successful adoption of technology is becoming increasingly important to functional independence. The present article reports findings from the Center for Research and Education on Aging and Technology Enhancement (CREATE) on the use of technology among community-dwelling adults. The sample included 1,204 individuals ranging in age from 18-91 years. All participants completed a battery that included measures of demographic characteristics, self-rated health, experience with technology, attitudes toward computers, and component cognitive abilities. Findings indicate that the older adults were less likely than younger adults to use technology in general, computers, and the World Wide Web. The results also indicate that computer anxiety, fluid intelligence, and crystallized intelligence were important predictors of the use of technology. The relationship between age and adoption of technology was mediated by cognitive abilities, computer self-efficacy, and computer anxiety. These findings are discussed in terms of training strategies to promote technology adoption. 相似文献
994.
Studzinski CM Christie LA Araujo JA Burnham WM Head E Cotman CW Milgram NW 《Neurobiology of learning and memory》2006,86(2):197-204
Visuospatial learning and memory impairments are an early marker for age-related cognitive decline and Alzheimer's disease. Similar to humans, aged dogs show visuospatial learning and memory deficits (). One hundred and nine beagle dogs ranging between 0.25 and 11.99 years were tested on a visuospatial delayed non-matching to position (DNMP) task to better characterize the progression of visuospatial deficits in the dog. Age predicted 48.2% of the variability in learning the DNMP, with dogs ranging from 1 to 11.99 years generally making more errors with increasing age. By contrast, puppies (<1 year) likely were showing developmental deficits, possibly due to an immature prefrontal cortex. Mild visuospatial deficits were detected by 6 years, which precedes the typical onset of amyloid-beta (Abeta) accumulation in the dog brain by two years, and can serve as an early marker for cognitive decline in the dog. These findings suggest that (1) age-related changes in visuospatial function in the dog models that seen in humans, further validating the dog as a model for human aging and dementia; and (2) other mechanisms, such as oxidative stress, soluble Abeta oligomers or cholinergic deficits, are likely contributing to the early impairment. 相似文献
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997.
Structural equation modeling (SEM) can be adapted in a relatively straightforward fashion to analyze data from interchangeable dyads (i.e., dyads in which the 2 members cannot be differentiated). The authors describe a general strategy for SEM model estimation, comparison, and fit assessment that can be used with either dyad-level or pairwise (double-entered) dyadic data. They present applications illustrating this approach with the actor-partner interdependence model, confirmatory factor analysis, and latent growth curve analysis. 相似文献
998.
Poor socioeconomic status and African American (AA) ethnicity contribute to an increased risk of obesity for many inner city children. One hundred and forty six AA children and 108 AA parents attending an inner city health fair completed surveys regarding perceptions of their own (or their child's) weight and the impact of weight on health. The children were measured and their body mass indexes were calculated. Thirty-seven percent of the child respondents (n = 52) were at risk of overweight or overweight; of these, 67% perceived themselves as normal weight, and 77% thought their weight was healthy. Weighing more was felt to be healthy by 17% of children and 29% of parents. Of 39 parents whose children were at risk of overweight or overweight, 68% felt their child's weight was normal and 80% thought it was healthy. These results suggest that inner city AA children and their parents often do not recognize being overweight or the health implications of being overweight. 相似文献
999.
The relation of adolescents' experiencing parental divorce, their perception of parents' characteristics, and their perception of the ideal mate's characteristics was investigated. One hundred adolescents from intact families and 79 from nonintact families were asked to rank both the degree to which each of 40 personality traits characterized their parents and the degree to which each characterized an ideal partner. The results indicated that there was no significant difference between adolescents from intact and nonintact families in the independence of their characterizations of their ideal mate and of their parents. However, differences were found on some of the personality dimensions that were investigated. These and other findings are discussed within the framework of psychoanalytic theory. 相似文献
1000.
This study evaluated the efficacy of behavioral and cognitive-behavioral one-session exposure treatment procedures with and without programmed generalization for participants with small animal phobias. Forty participants were randomly assigned to the treatment and generalization conditions. Both treatments produced significant improvements from pre-test to post-test and these results were maintained for 1 year. The treatment effect sizes ranged from large to very large across behavioral, self-report, and subjectively rated measures. Participants in the behavioral treatment condition reported that the treatment was significantly more intrusive than participants in the cognitive-behavioral treatment group. The programmed generalization condition did not produce additional measured benefit. The results are discussed in terms of the overall effectiveness of one-session exposure treatment components for small animal phobias. 相似文献