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921.
We report that post-training inactivation of basolateral amygdala region (BLA) with muscimol impaired memory for contextual-fear conditioning (as measured by freezing) and intra-BLA norepinephrine enhanced this memory. However, pre-exposure to the context eliminated both of these effects. These findings provide a likely explanation of why an earler study failed to observe that the BLA modulates contextual fear conditioning-they pre-exposed their rats to the context. These results also suggest that the amygdala modulates the storage of the context fear memory and may do so by influencing the storage of the representation of the context in which the shock occurred.  相似文献   
922.
The objective of this study was to determine the role of health beliefs in genetic amniocentesis acceptance in a diverse racial-ethnic population. Participants completed a previously-validated questionnaire consisting of three sections: (1) demographics, (2) amniocentesis knowledge, and (3) health beliefs, which assessed perceived susceptibility, seriousness of potential impact, benefits of testing, and barriers to testing. The results showed that Hispanic women were less likely to accept amniocentesis (51.5% vs. Caucasian 82.8%, African American 82.9%, Asian 82.8%). Education level was the only demographic factor higher among acceptors. Women who accepted amniocentesis had higher perceived seriousness, susceptibility, and benefits HBM scores and higher knowledge scores than women who declined. HBM scores and knowledge predicted the amniocentesis decision correctly 91.5% of the time. Individual health beliefs and knowledge play a greater role in genetic amniocentesis acceptance than do demographic factors such as race-ethnicity.  相似文献   
923.
Previous studies have suggested that face identification is more sensitive to variations in spatial frequency content than object recognition, but none have compared how sensitive the 2 processes are to variations in spatial frequency overlap (SFO). The authors tested face and object matching accuracy under varying SFO conditions. Their results showed that object recognition was more robust to SFO variations than face recognition and that the vulnerability of faces was not due to reliance on configural processing. They suggest that variations in sensitivity to SFO help explain the vulnerability of face recognition to changes in image format and the lack of a middle-frequency advantage in object recognition.  相似文献   
924.
Although the theoretical importance of perspective taking has long been recognized, surprisingly little work has documented the cognitions associated with attempts to imagine another's point of view. To explore this issue and to determine whether perspective taking increases the likelihood of self-related thoughts, two experiments were carried out. In the first, a thought-listing procedure was used to assess observer cognitions; in the second, a less reactive measure was used. Instructions to imagine the self in the target's position and instructions simply to imagine the target's perspective produced increased levels of self-related cognition relative to a traditional control condition; the imagine-self condition also produced more self-thoughts and fewer target thoughts than did the imagine-target condition. The control condition produced thoughts suggesting that the observers were distancing themselves from the target. Observers receiving no instructions at all reported cognitions that closely resembled those of observers who received imagine-target instructions.  相似文献   
925.
The present study examined the effects of a pre-movement delay on the kinematics of prehension in middle childhood. Twenty-five children between the ages of 5 and 11 years made visually open-loop reaches to two different sized objects at two different distances along the midline. Reaches took place either (i) immediately, or (ii) 2 s after the occlusion of the stimulus. In all age groups, reaches following the pre-movement delay were characterised by longer movement durations, lower peak velocities, larger peak grip apertures and longer time spent in the final slow phase of the movement. This pattern of results suggests that the representations that control the transport and grasp component are affected similarly by delay, and is consistent with the results previously reported for adults. Such representations therefore appear to develop before the age of 5.  相似文献   
926.
Domestic dogs (Canis familiaris) perform above chance on invisible displacement tasks despite showing few other signs of possessing the necessary representational abilities. Four experiments investigated how dogs find an object that has been hidden in 1 of 3 opaque boxes. Dogs passed the task under a variety of control conditions, but only if the device used to displace the object ended up adjacent to the target box after the displacement. These results suggest that the search behavior of dogs was guided by simple associative rules rather than mental representation of the object's past trajectory. In contrast, Experiment 5 found that on the same task, 18- and 24-month-old children showed no disparity between trials in which the displacement device was adjacent or nonadjacent to the target box.  相似文献   
927.
This study examined slow wave (SW) event-related brain potential (ERP) amplitudes in response to happy, neutral, and sad faces during a working memory task to further identify the associated component processes and physiological changes of mood-congruent memory biases in individuals with and without major depression. The results suggest that individuals with and without a diagnosis of major depressive disorder (MDD) differentially maintain valenced facial information in their working memory. Specifically, the nondepressed individuals displayed a marked reduction in SW amplitude to the negative faces. Individuals with MDD exhibited equivalent SW amplitudes for positive and negative facial stimuli. Results are discussed in terms of avoidance coping, previous ERP studies of working memory, and facial recognition deficits in individuals with MDD.  相似文献   
928.
929.
Since the early 1960s, a number of instruments, reflecting a broad range of assessment methods, have been developed to assist in the evaluation of competency to stand trial. These instruments have taken various forms including checklists, self-report questionnaires, sentence-completion tasks, and interview-based instruments with and without criterion-based scoring. This article reviews these assessment instruments with a specific focus on their contribution to the competency evaluation process. Furthermore, relevant issues and considerations regarding the use of these instruments are outlined, including a comparison of screening versus assessment applications of these instruments, balancing standardized approaches with individualized assessments, the integration of instrumentally derived data with other components of a competency evaluation, and the communication of results to the fact finder. Each of these issues is discussed in relation to specific competency assessment instruments. Overall, we argue that each of the competency assessment instruments developed to date can make a contribution to the competency evaluation process and this article serves to delineate those areas in which these contributions are made.  相似文献   
930.
The assessment of worry among older adults typically has involved measures designed with younger cohorts. Because of special concerns in assessing older adults, modifications to existing instruments may be necessary. Addressing equivocal factor analytic data on the Penn State Worry Questionnaire (PSWQ) among younger adults, the authors conducted confirmatory factor analyses to evaluate the generalizability of previous models to older adults with generalized anxiety disorder. Data fit poorly with established single- and two-factor models. The single-factor model was modified, resulting in the elimination of 8 items, strong fit indices, high internal consistency, adequate test-retest reliability, and good convergent and divergent validity. Further psychometric work is required to assess whether the revised model is a more parsimonious method to assess late-life anxiety.  相似文献   
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