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281.
To navigate efficiently, a traveler must establish a heading using a frame of reference. A large body of evidence has indicated that humans and a variety of nonhuman animals utilize the geometry, or shape, of enclosed spaces as a frame of reference to determine their heading. An important and yet unresolved question is whether shape information from arrays of discrete objects and enclosed environments are represented, and utilized, in the same way. In the present study, rats were presented with a reference memory task in which they had to find water that was hidden in 1 of 4 discrete and unique objects placed at the vertices of a rectangle. The results indicate that rats could utilize both feature and geometry cues to locate the hidden goal. The rats' performance declined during transformation tests using a triangular array, indicating that the rats may have encoded the primary axis of the object array, rather than local cues, to direct their search.  相似文献   
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283.
ABSTRACT— We review association studies that have examined the genetic basis of eating disorders. Overall, findings suggest that serotonin, brain-derived neurotrophic factor, and estrogen genes may be important for the development of the disorders. These neuronal systems influence behavioral and personality characteristics (e.g., anxiety, food intake) that are disrupted in eating disorders. Future studies would benefit from larger sample sizes and inclusion of behavioral and personality covariates in analyses. Consideration of the mechanisms of genetic effects and interactions between genes and environment is also needed to extend conceptualizations of the genetic basis of these disorders.  相似文献   
284.
This paper addresses the issue of variances in training modalities and how this is linked to one's personal experience of training and to one's analytic lineage. The author, who bases his reflections on discussions held during the yearly directors of training meeting of the North American Jungian Societies, suggests that, while each institute aims to provide an 'ideal' training programme for its candidates, the philosophy underlying how this ideal is defined depends, in large part, on the theoretical and philosophical orientation of the founding fathers and mothers. This results in a form of analytic lineage that necessarily impacts on the form and content of the 'ideal' programme. Shadow issues related to analytic lineage in the admissions procedures, case consultation, exam committees and review committees are presented. Motivation for why we choose to train and reflections on what makes an analyst 'Jungian' are explored.  相似文献   
285.
The purpose of the present study was to examine the relationship among Effort, Reward, and Overcommitment dimensions of Siegrist's Effort-Reward Imbalance Model and Psychological Distress in a sample of 78 Canadian police officers. Ages of respondents ranged between 24 and 56 years (M=36.1, SD=8.0). 30% of respondents had been in policing for 16 years or more, 24% between 6 and 15 years, and 44% for 5 years or less. Ordinary least-squares regression was used to evaluate the relationship between the independent and dependent variables. After adjusting for age, sex, education, and marital status, higher levels of Effort-Reward Imbalance and Overcommitment were associated with greater Psychological Distress. Present findings support the utility of the model in this particular occupational group and add to the increasing literature suggesting association of Effort-Reward Imbalance, Overcommitment, and reduced mental health.  相似文献   
286.
Since the brain neurotransmitter changes characterising panic disorder remain uncertain, we quantified brain noradrenaline and serotonin turnover in patients with panic disorder, in the absence of a panic attack. Thirty-four untreated patients with panic disorder and 24 matched healthy volunteers were studied. A novel method utilising internal jugular venous sampling, with thermodilution measurement of jugular blood flow, was used to directly quantify brain monoamine turnover, by measuring the overflow of noradrenaline and serotonin metabolites from the brain. Radiographic depiction of brain venous sinuses allowed differential venous sampling from cortical and subcortical regions. The relation of brain serotonin turnover to serotonin transporter genotype and panic disorder severity were evaluated, and the influence of an SSRI drug, citalopram, on serotonin turnover investigated. Brain noradrenaline turnover in panic disorder patients was similar to that in healthy subjects. In contrast, brain serotonin turnover, estimated from jugular venous overflow of the metabolite, 5-hydroxyindole acetic acid, was increased approximately 4-fold in subcortical brain regions and in the cerebral cortex (P < 0.01). Serotonin turnover was highest in patients with the most severe disease, was unrelated to serotonin transporter genotype, and was reduced by citalopram (P < 0.01). Normal brain noradrenaline turnover in panic disorder patients argues against primary importance of the locus coeruleus in this condition. The marked increase in serotonin turnover, in the absence of a panic attack, possibly represents an important underlying neurotransmitter substrate for the disorder, although this point remains uncertain. Support for this interpretation comes from the direct relationship which existed between serotonin turnover and illness severity, and the finding that SSRI administration reduced serotonin turnover. Serotonin transporter genotyping suggested that increased whole brain serotonin turnover most likely derived not from impaired serotonin reuptake, but from increased firing in serotonergic midbrain raphe neurons projecting to both subcortical brain regions and the cerebral cortex.  相似文献   
287.
The current study examined the MMPI-2 Restructured Clinical (RC) scales (Tellegen et al., MMPI-2 Restructured Clinical (RC) scales: Development, validation, and interpretation. Minneapolis: University of Minnesota Press, 2003) in a sample of 1,091 bariatric surgery candidates. The RC scales were developed to address concerns about limited discriminant validity of the Clinical scales. Internal consistency and external validity analyses were conducted to evaluate the RC scales in this setting. Results indicated that the RC scales are generally more internally consistent than the Clinical scales and display significantly better convergent and discriminant validity in predicting a variety of behavioral, psychological, and developmental variables relevant to preoperative bariatric psychological evaluations. Implications of the results and recommendations for future research with the RC scales in medical settings are discussed.  相似文献   
288.
Two experiments examine how collaboration influences visual search performance. Working with a partner or on their own, participants reported whether a target was present or absent in briefly presented search displays. We compared the search performance of individuals working together (collaborative pairs) with the pooled responses of the individuals working alone (nominal pairs). Collaborative pairs were less likely than nominal pairs to correctly detect a target and they were less likely to make false alarms. Signal detection analyses revealed that collaborative pairs were more sensitive to the presence of the target and had a more conservative response bias than the nominal pairs. This pattern was observed even when the presence of another individual was matched across pairs. The results are discussed in the context of task-sharing, social loafing and current theories of visual search.  相似文献   
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Suicide remains a leading cause of death among youth, and suicide ideation and behavior are relatively common in both normal and clinical populations. Clinicians working with young people must assess for the presence of suicidal ideation, suicidal behavior, and other risk factors, in order to determine the level of risk. This paper provides the clinician with a summary of risk factors for youth suicide, as well as providing standardized terminology to enhance assessment of suicidal ideation and behavior.  相似文献   
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