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71.
Severe traumatic brain injury: some effects on family caregivers   总被引:1,自引:0,他引:1  
This study assesses the effects of severe traumatic brain injuries on family members and functioning-a topic of interest for those working with survivors and their families. This issue is receiving increased attention as recent findings suggest that family adjustment influences outcome for brain-injured persons. The Family Environment Scale and the Profile of Mood States were completed by 25 individuals who had a family member with a severe traumatic brain injury. These scales were also completed by a comparison group of 32 individuals who had no brain-injured family member. In terms of family functioning, the findings suggest that, when a family member suffers a severe traumatic brain injury, depression may be elevated, along with a decreased ability to express feelings, decreased time and energy for social and recreational activities, and increased control in comparison to families without a brain-injured member. While this might contribute to family isolation which could last for many years, the overall finding of the present study was that caregiver families were coping adequately.  相似文献   
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The objective of this document is to provide health care professionals with recommendations for genetic counseling and testing of individuals with a suspected or confirmed diagnosis of Fabry disease, with a family history of Fabry disease, and those identified as female carriers of Fabry disease. These recommendations are the opinions of a multicenter working group of genetic counselors, medical geneticists, and other health professionals with expertise in Fabry disease counseling, as well as an individual with Fabry disease who is a founder of a Fabry disease patient advocacy group in the United States. The recommendations are U.S. Preventive Task Force Class III, and they are based on clinical experience, a review of pertinent English-language articles, and reports of expert committees. This document reviews the genetics of Fabry disease, the indications for genetic testing and interpretation of results, psychosocial considerations, and references for professional and patient resources. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. The professional judgment of a healthcare provider, familiar with the facts and circumstances of a specific case, will always supersede these recommendations.  相似文献   
74.
Conditioned fear responses to a tone paired with footshock rapidly extinguish when the tone is presented in the absence of the shock. Rather than erase conditioning, extinction is thought to involve the formation of new memory. In support of this, extinguished freezing spontaneously recovers with the passage of time. It is not known, however, how long extinction memory lasts or whether extinction interferes with consolidation of conditioning if given on the same day. To address this, we gave rats 7 trials of auditory fear conditioning followed 1 h later by 20 extinction trials, and tested for spontaneous recovery after a delay of 0, 1, 2, 4, 6, 10, or 14 d. Conditioned freezing to the tone gradually recovered with time to reach 100% by day 10. No-extinction controls indicated that the increase in freezing with time was not owing to incubation of conditioning memory. Complete spontaneous recovery indicates that extinction training given 1 h after conditioning does not interfere with the consolidation of conditioning memory. Despite complete recovery of freezing, rats showed savings in their rate of re-extinction, indicating persistence of extinction memory. These data support the idea that conditioning and extinction of fear are learned by independent systems, each able to retain a long-term memory.  相似文献   
75.
Needham A  Dueker G  Lockhead G 《Cognition》2005,94(3):215-240
Four- and-a-half-month-old infants' (N = 100) category formation and use was studied in a series of five experiments. For each experiment, the test events featured a display composed of a cylinder and a box. Previous research showed that this display is not clearly parsed as a single unit or as two separate units by infants of this age. Immediately prior to testing, infants were shown a set of category exemplars. Knowledge about this category could help infants disambiguate the test display, which contained a novel exemplar of this category. Clear interpretation of the test display as composed of two separate units (as indicated by infants' longer looking at the move-together than at the move-apart test event) was taken as evidence of category formation and use. In Experiments 1 and 5, infants' prior experience with a set of three different boxes that were similar to the test box facilitated their segregation of the test display. Experiment 2 showed that three different exemplars are necessary: prior experience with any two of the three boxes used in Experiment 1 did not facilitate infants' segregation of the test display. Experiment 3 showed that variability in the exemplar set is necessary: prior experience with three identical boxes did not facilitate infants' segregation of the test display. Experiment 4 showed that under these conditions of very brief prior exposure, similarity between the exemplar set and test box is necessary: prior experience with three different boxes that were not very similar to the test box did not facilitate infants' segregation of the test display. Together, these findings suggest that: (a) number of exemplars, variability, and similarity in the exemplar set are important for infants' category formation, and (b) infants use their category knowledge to determine the boundaries of the objects in a display.  相似文献   
76.
Negatively valenced stimuli foster cognitive impairment in schizotypy and schizophrenia. To identify relevant brain mechanisms, the authors had 16 positive-schizotypy and 16 control participants perform an emotional Stroop task, judging the ink color of negative and neutral words during functional magnetic resonance imaging (fMRI) of regional brain activity. Schizotypy individuals showed increased right and decreased left activity in dorsolateral prefrontal cortex, indicating a deficit in maintenance of attentional set in the presence of negative emotional distractors. They also showed abnormal activity in ventral limbic areas, including decreased activity in nucleus accumbens and increased activity in hippocampus and amygdala, a circuit involved in the integration of cognitive and affective processes. These results indicate that aspects of emotion-cognition processes and the brain mechanisms that implement them are similar in schizotypy and schizophrenia.  相似文献   
77.
The present study evaluated the effects of a lag differential reinforcement contingency on 2 students' activity selections using reversal designs. Results showed that the lag contingency was responsible for promoting increased novel selections, engagement in diverse activities, and greater progress with respect to programmed academic activities.  相似文献   
78.
The structural view of rational acceptance is a commitment to developing a logical calculus to express rationally accepted propositions sufficient to represent valid argument forms constructed from rationally accepted formulas. This essay argues for this project by observing that a satisfactory solution to the lottery paradox and the paradox of the preface calls for a theory that both (i) offers the facilities to represent accepting less than certain propositions within an interpreted artificial language and (ii) provides a logical calculus of rationally accepted formulas that preserves rational acceptance under consequence. The essay explores the merit and scope of the structural view by observing that some limitations to a recent framework advanced James Hawthorne and Luc Bovens are traced to their framework satisfying the first of these two conditions but not the second.  相似文献   
79.
Knowing an item's category helps us predict its unknown properties. Previous studies suggest that when asked to evaluate the probability of an unknown property, people tend to consider only an item's most likely category, ignoring alternative categories. In the present study, property prediction took the form of either a probability rating or a speeded binary-choice judgment. In keeping with past findings, the subjects ignored alternative categories in their probability ratings. However, their binary-choice judgments were influenced by alternative categories. This novel finding suggests that the way in which category knowledge is used in prediction depends critically on the form of the prediction.  相似文献   
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