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941.
Hjort H  Frisén A 《Adolescence》2006,41(161):141-163
The saliency of ethnicity and ethnic identity is influenced by contextual circumstances. In Bosnia-Herzegovina, due to the current ethno-political situation, ethnicity and ethnic identity most likely are important aspects of adolescents' lives. The main purpose of this study is to describe a group of young Mostarians in relation to ethnic identity and reconciliation. Focus is on the participants' perspectives on these subjects and the meanings they attribute to the concepts. A total of 89 young Mostarians are included in the study. A third of the participants are members of a local peace- and reconciliation-building organization, Koraci Nade. Results show that ethnic identity is highly salient for the group. While participants demonstrate strong emotional attachment to their ethnic group, exploration of ethnic identity is less reported. With regard to reconciliation, the participants perceive it as very desirable and show a personal and integrated relation to the concept. However, their definitions of the concept are vague as to what constitutes the process of reconciliation. Although of great importance to the members, participation in the peace-building organization was not found to enhance either ethnic identity or cross-ethnic friendships.  相似文献   
942.
Adaptive motor actions require prior knowledge of instrumental contingencies. With practice, these actions can become highly automatic in nature. However, the molecular and anatomical substrates mediating these related forms of learning are not understood. In the present study, we used in situ hybridization to measure the mRNA levels of two immediate early genes (IEGs) in an instrumental paradigm where rats learned to lever-press for food. We report that after three training sessions, Homer 1a and Zif268 (an effector and regulatory IEG, respectively) were significantly induced within an extensive corticostriatal network relative to untrained controls. With extended training (23 sessions), however, a shift in the expression patterns of the two genes was evident. Expression of Homer 1a (official symbol Homer1) decreased significantly in frontal and cingulate cortices, whereas striatal expression was generally maintained. Interestingly, Homer 1a expression markedly increased with extensive training in the ventrolateral region of the striatum (VLS) relative to early learners, suggesting that plasticity in the VLS is required for the efficient production of the learned behavior or in habit formation. Zif268 (official symbol Egr1) expression generally decreased with extensive training; however, these changes were not significant. These results demonstrate for the first time, on a molecular level, a dynamic shift in the contribution of corticostriatal systems mediating the early acquisition and consolidation of goal-directed responses to those engaged after extensive training.  相似文献   
943.
Although masculinity ideology (MI) has been shown to predict men’s sexual risk-taking, less is known about MI’s contribution to men’s beliefs about women and their sexual bodies. Accordingly, we examined associations between masculine ideology, media consumption, and men’s attitudes about women’s reproductive body functions among a sample of 656 undergraduate men. Participants completed measures assessing their endorsement of traditional gender ideologies, their levels of media exposure and engagement, and their attitudes toward childbirth and breastfeeding. It was hypothesized that media use would contribute to traditional MI, and that traditional MI would contribute to negative views about breastfeeding and childbirth. Results supported these individual connections, but not a mediated model. Discussion focuses on implications of these findings for women’s lives.  相似文献   
944.
This study examined how specific features of adaptive tests are related to test takers' reactions. Participants took a computer-adaptive test in which 2 features, difficulty of the initial item and difficulty of subsequent items, were manipulated, then responded to questionnaires assessing their reactions to the test. The data show that the relationship between a test's objective difficulty, which was determined by the 2 manipulated test characteristics, and reactions was fully mediated by perceived performance. Additional analyses evaluated the impact of feedback on reactions to the adaptive test. In general, feedback that was consistent with perceptions of performance was positively related to reactions. The results suggest that minor changes to the design of an adaptive test may potentially enhance examinees' reactions.  相似文献   
945.
An analysis of the relationship among the Personality Assessment Inventory (PAI; Morey, 1991, 1996) Drug Problems (DRG) scale scores, the Addiction Severity Index (ASI; McLellan et al., 1992) scores, and urine toxicology reports revealed that the PAI Drug Problem scale scores of 100 substance-using and substance-abusing men and women were distributed in a manner that was in agreement with the guidelines suggested by Morey (1991, 1996) in the PAI manual. There were significant correlations among the PAI DRG scale and the ASI scales related to frequency of use, negative consequences of use, and need and desire for treatment. Overall, higher scores did reflect both more serious involvements with drug use and more serious problems as a consequence of their involvement.  相似文献   
946.
The short form of the Coopersmith Self-Esteem Inventory (SEI) was evaluated for gender bias. The authors replicated a study by L. Francis and D. James (1998) and administered the SEI to 361 middle and high school students (146 boys, 2l5 girls). They found that gender bias existed in 6 of the 25 items on the SEI, with 5 of those items favoring boys. Because recent literature indicates that male and female adolescents experience problems in different areas of their lives, the authors suggest that researchers consider such differences when selecting items for a standardized measure.  相似文献   
947.
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.  相似文献   
948.
Higgins  Louise T.  Zheng  Mo  Liu  Yali  Sun  Chun Hui 《Sex roles》2002,46(3-4):75-89
This paper reports a survey carried out among 505 university students in China and 338 students in the United Kingdom. The survey included questions on attitudes toward mate-selection preferences, marriage, and sexual behavior. The findings show that traditional values in mate-selection preferences persist more in China than in the United Kingdom and indicate that, despite a profound social revolution over the last two decades, a relatively conservative sexual culture still exists in China today. Traditional morality and attitudes prevail especially among women. Gender and culture differences are discussed.  相似文献   
949.
The medium spiny neurons of the nucleus accumbens receive a unique convergence of dopaminergic and glutamatergic inputs from regions associated with motivational, cognitive, and sensory processes. Long-term forms of plasticity in the nucleus accumbens associated with such processes as appetitive learning and drug addiction may require coactivation of both dopamine D1 and glutamate N-methyl-D-aspartate (NMDA) receptors. This notion implies that an intracellular mechanism is likely to be involved in these long-term neuroadaptive processes. The present series of experiments examined the effects of intra-accumbens microinfusion of protein kinase inhibitors on acquisition of an instrumental task, lever-pressing for food. Male Sprague-Dawley rats were bilaterally implanted with chronic indwelling cannulae aimed at the nucleus accumbens core. Following recovery, animals were food-restricted and subsequently trained for operant responding. The broad-based serine/threonine kinase inhibitor H-7 (5 or 27 nmol per side) dose-dependently impaired learning when infused immediately after testing on days 1-4. Rp-cAMPS, a cAMP-dependent protein kinase (PKA) inhibitor, also impaired learning regardless of whether it was infused immediately before (5 or 20 nmol) or immediately after (10 nmol) testing on days 1-4. Rp-cAMPS (10 nmol) also inhibited learning when infused 1 h after testing, though to a lesser extent than when administered before or immediately after testing. The PKA stimulator Sp-cAMPS (5 or 20 nmol) also impaired learning when infused before testing, suggesting that there is an optimal level of PKA activity required for learning. None of the drugs used produced nonspecific motor or feeding effects. These results provide evidence supporting the involvement of nucleus accumbens PKA in appetitive learning and suggest that this kinase may be involved in long-term changes associated with this and other motivationally based neuroadaptive processes.  相似文献   
950.
Prolonged exposure to a reciprocating motion that is tracked by the eyes results in diminished extent of perceived motion. Investigation of this effect showed that it becomes manifest only in perceived motion that is caused by ocular pursuit, but that it is not an eye muscle effect. It may consist in a changed evaluation of eye movements. The results throw some light on the relations between the processes that are caused by different stimuli for motion.  相似文献   
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