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181.
The main aim of this study was to assess perceptions of and satisfaction with retirement among 1,686 recently retired people from 6 European Union countries. The authors compared their responses to a set of questions taken from the Retirement Satisfaction Inventory (F. J. Floyd et al., 1992). The first significant result was that Belgian, British, Finnish, French, and Spanish retirees all expressed very similar assessments of life satisfaction, whereas Portuguese retirees expressed a lower level of satisfaction. The 2nd result was that the major determinants of overall satisfaction in the 6 countries were (a) health and resources and (b) anticipated satisfaction. Finally, the data revealed that cultural background only accounted for a limited amount of variance in overall satisfaction with retirement.  相似文献   
182.
Knowing the most likely reasons for suicide might increase the chances to identify the early signs of suicide. Folkloric tales on suicide among animals are a possible source of such information, since people probably explain animal suicide using the same reasons they would apply to their kin. Modern naturalistic studies ave found little evidence of self-harming conduct among nonhuman species. Nevertheless, mythological accounts often report suicidal behaviour among animals. Claudius Aelian's De natura animalium, a classic in its genre, written in the 2nd century AD, reports 21 cases of suicide among animals. In Aelian's tales, the severing of social ties emerges as an important motive for suicide, together with incest and rage caused by adultery. Paying attention to the mechanisms leading to suicide described in ancient mythology may help us understand unusual and uncommon motives for suicide and the reasons people feel suicidal.  相似文献   
183.
The practice and study of clinical neuropsychology is considered an empirical enterprise. However, such an approach may result in missing the more humanistic or phenomenological side of the experience of brain dysfunction. This addresses a personal journey rather than a professional and scientific one. In doing so, the limits of the discipline and the suffering and value of the experience of the illness are presented. An earlier version of this article was presented as the Presidential Address for the Division 40 (Clinical Neuropsychology) of the American Psychological Association in August of 2003.  相似文献   
184.
Switching between two different tasks normally results in an impairment in people's performance known as a switch cost, typically measured as an increase in reaction time (RT) and errors compared to a situation in which no task switch is required. Researchers in task switching have suggested that this switch cost is the behavioural manifestation of the task set reconfiguration processes that are necessary to perform the upcoming task. However, an examination of the literature in task switching reveals apparently contradictory results about the nature of task set reconfiguration processes. In Experiment 1, we addressed this issue by comparing participants' performance in two different experimental conditions: predictable task switching and random task switching. In the predictable switch condition the switch cost completely vanished after the first repetition of the new task. However, in the random switch condition, while the difference between switch and repetition trials was not significant, we observed a significant reduction in RT between the first and second repetition of the new task. In Experiment 2, we further investigated the pattern of task set reconfiguration in the random switch situation. The results showed a progressive reduction of participants' response latencies across repetitions of the same task. The present study demonstrates that, whereas the results in predictable switching conditions are compatible with an exogenous-reconfiguration hypothesis, random task switching produces a more gradual, decay-like switch cost reduction with task repetition.  相似文献   
185.
186.
Mutations in the amyloid precursor protein (APP) gene inducing abnormal processing and deposition of beta-amyloid protein in the brain have been implicated in the pathogenesis of Alzheimer's disease (AD). Although Tg2576 mice with the Swedish mutation (hAPPswe) exhibit age-related Abeta-plaque formation in brain regions like the hippocampus, the amygdala, and the cortex, these mice show a rather specific deficit in hippocampal-dependent learning and memory tasks. In view of recent findings showing that neural systems subserving different forms of learning are not simply independent but that depressing or enhancing one system affects learning in another system, we decided to investigate fronto-striatal synaptic plasticity and related procedural learning in these mutants. Fronto-striatal long-term depression (LTD) induced by tetanic stimulation of the cortico-striatal input was similar in Tg2576 and wild-type control mice. Behavioral data, however, pointed to an enhancement of procedural learning in the mutants that showed robust motor-based learning in the cross maze and higher active avoidance scores. Thus, in this mouse model of AD, an intact striatal function associated with an impaired hippocampal function seems to provide neural conditions favorable to procedural learning. Our results suggest that focusing on preserved or enhanced forms of learning in AD patients might be of interest to describe the functional reorganization of the brain when one memory system is selectively compromised by neurological disease.  相似文献   
187.
Current evidence appoints a central role to cholinergic interneurons in modulating striatal function. Recently, a long-term potentiation (LTP) of synaptic transmission has been reported to occur in these neurons. The relationship between the pattern of cortico/thalamostriatal fibers stimulation, the consequent changes in the intracellular calcium concentration ([Ca2+]i), and the induction of synaptic plasticity was investigated in striatal cholinergic interneurons from a rat corticostriatal slice preparation by means of combined electrophysiological intracellular recordings and microfluorometric techniques. Different protocols of stimulation were considered, varying both the frequency and the duration of the train of stimuli. High-frequency stimulation (HFS) (three trains at 100 Hz for 3 sec, 20-sec interval) induced a rise in [Ca2+]i, exceeding by fivefold the resting level, and caused a LTP of synaptic transmission. Tetanic stimulation delivered at lower frequencies (5-30 Hz) failed to induce long-term changes of synaptic efficacy. The observed elevation in [Ca2+]i during HFS was primarily mediated by L-type high-voltage activated (HVA)-Ca2+ channels, as it was fully prevented by nifedipine. Conversely, blockade of NMDA and AMPA glutamate receptor did not affect either LTP or the magnitude of the [Ca2+]i rise. Interestingly, the pharmacological analysis of the post-tetanic depolarizing postsynaptic potential (DPSP) revealed that LTP was attributable, to a large extent, to the potentiation of the GABA(A)-mediated component. In conclusion, the expression of LTP in striatal cholinergic interneurons is a selective response to a precise stimulation pattern of induction requiring a critical rise in [Ca2+]i.  相似文献   
188.
Leptin is an adipocyte-derived hormone, which is involved predominantly in the long-term regulation of body weight and energy balance by acting as a hunger suppressant signal to the brain. Leptin is also involved in the modulation of reproduction, immune function, physical activity, and some endogenous endocrine axes. Since anorexia nervosa (AN) and bulimia nervosa (BN) are characterized by abnormal eating behaviors, dysregulation of endogenous endocrine axes, alterations of reproductive and immune functions, and increased physical activity, extensive research has been carried out in the last decade in order to ascertain a role of this hormone in the pathophysiology of these syndromes. In this article, we review the available data on leptin physiology in patients with eating disorders. These data support the idea that leptin is not directly involved in the etiology of AN or BN. However, malnutrition-induced alterations in its physiology may contribute to the genesis and/or the maintenance of some clinical manifestations of AN and BN and may have an impact on the prognosis of AN.  相似文献   
189.
Two experiments investigated the tendency of groups with members under high (vs. low) need for cognitive closure to develop an autocratic leadership structure in which some members dominate the discussion, constitute the "hubs" of communication, and influence the group more than other members. The first experiment found that high (vs. low) need for closure groups, as assessed via dispositional measure of the need for closure, manifested greater asymmetry of conversational floor control, such that members with autocratic interactional style were more conversationally dominant and influential than less autocratic members. The second experiment manipulated the need for closure via time pressure and utilized a social network analysis. Consistent with expectation, groups under time pressure (vs. no pressure) showed a greater asymmetry of participation, of centrality, and of prestige among the group members, such that the more focal members were perceived to exert the greater influence over the groups' decisions.  相似文献   
190.
Shneidman (e.g., 1998) has theorized that psychache--general psychological and emotional pain that reaches intolerable intensity--is an important suicide-related variable, and indeed, represents a source of suicidal behavior. This conceptualization, while prominent and clinically and intuitively appealing, has received relatively little empirical scrutiny. In this study, we determined whether an index closely related to psychache, psychological quality of life, would display a special and resilient association to suicidality among 60 adult psychiatric outpatients in Brazil. All patients underwent structured clinical interviews and completed various clinical and quality-of-life measures. We found that the association between psychological quality of life and suicidality remained, even when depression, hopelessness, and other domains of quality of life were controlled. Psychache appears to deserve its place among key suicide-related variables, and deserves the attention of clinicians working with suicidal people.  相似文献   
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