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151.
Cerebellar volumes show small positive correlations with cognitive ability in young adults, but no studies have examined this relationship in older adults. Furthermore, no studies have examined relationships between sizes of subareas of the cerebellum and cognitive ability. We hypothesized that size of the two areas of the neocerebellar vermis would correlate with a battery of eight cognitive tests in 50 men aged 65-70. Size of the neocerebellar areas of the vermis correlated positively with several cognitive tests (r's=.29-.37, p<.05), whilst sizes of other parts of the vermis did not correlate with any cognitive tests. Total cerebellar volumes correlated significantly with a test of nonverbal reasoning (r=.030, p=.42). These findings suggest a specific association of neocerebellar vermis size with variations in cognitive ability in older adults.  相似文献   
152.
The purpose of the present study was to evaluate the effectiveness of the Effective Learning Program (ELP) with students who are at high risk for dropping out of high school. The intervention sought to change external control expectancies to more internal ones, improve students' skills in building relationships with peers and adults, and increase graduation rates. Thirty-eight students considered at risk for dropping out of high school received the intervention. In addition, ELP-eligible students who did not receive the ELP intervention (n = 36) and regular education students (n = 50) from the same high school were compared with the students who received the ELP. A significantly greater percentage of ELP students graduated, became more internally controlled, achieved more as shown by standardized tests, and developed greater social skills and better relationships than their ELP-eligible but nonparticipating peers. The authors suggest that researchers identify which aspects of the ELP are responsible for the improvement in retention, achievement, and personal attributes.  相似文献   
153.
The present study investigated the role of psychosocial variables that are indicators for depressive symptomatology within a couple. The variables chosen for this study were conflict communication, marital adjustment, attachment, attribution style, and personality traits--all potentially specific indicators. A global factor analysis on all our measures revealed that our individual and relational measures were stable findings. We wanted to compare a dimensional and categorical view of depression. First, we focused on the total nonclinical sample, considering depression on a continuum, and studying the selected characteristics along with the varying degree of depressive complaints. The results highlighted the importance of individual characteristics (neuroticism and life satisfaction) covarying with the level of depressive symptomatology in the nonclinical sample (n = 186 couples). Second, in addition to this correlational design, we compared the group of most depressed subjects and their partners with a control sample (n = 34). Both approaches pointed to the same conclusion: individual characteristics covaried with mild depression, whereas couple characteristics only came into the picture with a higher level of depressive complaints. The lowest levels of depressive complaints were associated with individual co-morbidity only, whereas increasing complaints went along with additional relational complaints. Implications for assessment and future research are discussed.  相似文献   
154.
Much has been stated in the popular press about the effects of the events of 9/11/01 on employee attitudes about work. This study examined a large sample (N = 70,671) of employees of a multinational manufacturer whose annual employee survey data collection was interrupted by the events. After demonstrating measurement equivalence across time and countries, changes in attitudes pre- and post-9/11 were examined. Only negligible differences were found in Job Satisfaction, Supervisor Evaluation, Stress, and Organizational Commitment to Diversity for U.S. employees or for employees worldwide. Demographic differences in response to events were not found. Implications for understanding effects of stressful external events on employee perceptions of work are discussed.  相似文献   
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Studies of the hypothalamic-pituitary-adrenal (HPA) axis in persons with posttraumatic stress disorder (PTSD) have produced variable findings. This review focuses on the factors likely to have affected the outcome of these studies, including population characteristics and experimental design. Also discussed is a possible role for the adrenal neurosteroid dehydroepiandrosterone (DHEA) as a mediator of HPA axis adaptation to extreme stress and the psychiatric symptoms associated with PTSD. The antiglucocorticoid properties of DHEA may contribute to an upregulation of HPA axis responses as well as mitigate possible deleterious effects of high cortisol levels on the brain in some PTSD subpopulations. The neuromodulatory effects of DHEA and its metabolite DHEAS at gamma-aminobutyric acid and N-methyl-D-aspartate receptors in the brain may contribute to psychiatric symptoms associated with PTSD. The possible importance of other neurohormone systems in modulating HPA axis and symptom responses to traumatic stress is also discussed. Understanding the complex interactions of these stress-responsive neurosteroid and peptide systems may help explain the variability in patterns of HPA axis adaptation, brain changes, and psychiatric symptoms observed in PTSD and lead to better targeting of preventive and therapeutic interventions.  相似文献   
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A case of an adult who stutters and complains of a similar fluency problem when playing the trombone is reported. This is the fourth such report, with previous cases involving trumpet, flute, and horn playing.  相似文献   
160.
Several neuroimaging studies have reported that older adults show weaker activations in some brain areas together with stronger activations in other areas, compared with younger adults performing the same task. This pattern may reflect neural recruitment that compensates for age-related neural declines. The recruitment hypothesis was tested in a visual laterality study that investigated age differences in the efficiency of bihemispheric processing. Letter-matching tasks of varying complexity were performed under two conditions: (a) matching letters projected to the same visual field (hemisphere) and (b) matching letters projected to opposite visual fields (hemispheres). As predicted by the recruitment hypothesis, older adults generally performed better in the bilateral than unilateral condition, whereas younger adults showed this pattern onlyfor the most complex task. We discuss the relation between these results and neuroimaging evidence for recruitment, and the relevance of the present bihemispheric advantage to other evidence for age-related changes in interhemispheric transfer.  相似文献   
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