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Aggressive biting of an inanimate target by mice was studied. Males attacked the bite-target more frequently than females, but this difference disappeared after castration when the response rate of the males approached that of the females. Ovariectomizing the females had little effect on their bite-attack frequencies. Subsequent androgen injections restored the biting-attack frequency of the castrated males to preoperative levels but had little effect on the intact males. Estrogen had little effect on the response frequency of the females, whereas androgen produced a slight increase in their bite-attack frequency. Results indicate that androgen is critical for the maintenance of this aggressive response and that the single subject paradigm utilized in this study was a sensitive measure of aggressive tendencies in mice.  相似文献   
33.
The issue of personality and prejudice has been largely investigated in terms of authoritarianism and social dominance orientation. However, these seem more appropriately conceptualized as ideological attitudes than as personality dimensions. The authors describe a causal model linking dual dimensions of personality, social world view, ideological attitudes, and intergroup attitudes. Structural equation modeling with data from American and White Afrikaner students supported the model, suggesting that social conformity and belief in a dangerous world influence authoritarian attitudes, whereas toughmindedness and belief in a competitive jungle world influence social dominance attitudes, and these two ideological attitude dimensions influence intergroup attitudes. The model implies that dual motivational and cognitive processes, which may be activated by different kinds of situational and intergroup dynamics, may underlie 2 distinct dimensions of prejudice.  相似文献   
34.
Boundary extension is a tendency to remember close-up scenes as if they extended beyond the occluding boundaries. The authors explored the contributing factors using brief retention intervals and computer-generated images. Boundary extension turns out to be more complex than previously thought and is not linked to the effects of image magnification and field-of-view changes. Although this is consistent with the idea that boundary extension is the product of the activation of a mental schema that provides information of what is likely to exist outside the picture boundaries, the authors also found that properties of the object at the center of the picture can affect boundary extension independently of the information at the boundaries. In a test of boundary extension using stereograms, the effect does not seem to depend on amount of perceived depth, suggesting a weaker link to perception of space than previously hypothesized.  相似文献   
35.
These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client.  相似文献   
36.
Randomized clinical trials remain the most valid method of testing the efficacy and safety of treatments. While efforts to elucidate the genetic and neurodevelopmental bases of autism are underway, clinicians and families are in need of scientifically valid information on how to best treat patients with autism. The effectiveness of many interventions currently used in communities has not been adequately tested. Given the high public health relevance of autism treatment research and the low interest of the pharmaceutical industry in autism, the role of the National Institutes of Health in supporting this research is paramount. Among recently launched initiatives in autism clinical trials, there are the Research Units on Pediatric Psychopharmacology Autism Network and the network of centers for Studies to Advance Autism Research and Treatment. These and other government activities in the area of autism clinical trials are here briefly reviewed.  相似文献   
37.
Sleep is crucial to the 'off-line' consolidation of procedural memory. A recent study by Robertson et al. shows that this might hold true only if the task is trained explicitly, that is, with the subject being aware of the task structure. These new data add to emerging evidence that sleep-related memory consolidation involves an interaction between different memory systems.  相似文献   
38.
This study used growth curve modeling to explore whether practicing the task of estimating blood glucose levels would increase accuracy in children with type 1 diabetes. It was predicted that accuracy would improve with practice and that younger, anxious, poorly adjusted children would improve most. 43 attendees at a diabetes summer camp participated. Their mean age was 13.4 yr. (SD = 1.6). All were Euro-American, and 22 were girls. Change in accuracy was best represented by a quadratic function, and this model fit the data well. Overall, participants' accuracy improved initially and then deteriorated. Results indicate that older children were more likely to improve and then deteriorate. Younger children were more likely to improve and sustain those improvements. Results indicate that practicing the task of estimating is not an effective way to increase accuracy and may be contra-indicated. These results can help guide research and clinical use of glucose estimation in children.  相似文献   
39.
We present a computational model for human texture perception which assigns functional principles to the Gestalt laws of similarity and proximity. Motivated by early vision mechanisms, in the first stage, local texture features are extracted by utilizing multi-scale filtering and nonlinear spatial pooling. In the second stage, features are grouped according to the spatial feature binding model of the competitive layer model (CLM; Wersing et al. 2001). The CLM uses cooperative and competitive interactions in a recurrent network, where binding is expressed by the layer-wise coactivation of feature-representing neurons. The Gestalt law of similarity is expressed by a non-Euclidean distance measure in the abstract feature space with proximity being taken into account by a spatial component. To choose the stimulus dimensions which allow the most salient similarity-based texture segmentation, the feature similarity metrics is reduced to the directions of maximum variance. We show that our combined texture feature extraction and binding model performs segmentation in strong conformity with human perception. The examples range from classical microtextures and Brodatz textures to other classical Gestalt stimuli, which offer a new perspective on the role of texture for more abstract similarity grouping.  相似文献   
40.
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