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871.
Impulsive-compulsive sexual behavior is a little studied clinical phenomenon which affects approximately 5% to 6% of the population. In the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Text Revision, it is classified as an impulse control disorder not otherwise specified or a sexual disorder not otherwise specified. It may be placed in a possible new category in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition called substance and behavioral addictions. This clinical entity is reviewed and the merit of classifying it as an addiction is assessed. Information is presented regarding its diagnostic criteria, epidemiology, types of behavior it can involve, relationship to hypersexuality, comorbidities, treatment, and etiology. The data regarding this disorder and its overlap with chemical addiction is limited. If the two disorders are to be grouped together, further data are needed. 相似文献
872.
Hoffman HG Richards TL Bills AR Van Oostrom T Magula J Seibel EJ Sharar SR 《CNS spectrums》2006,11(1):45-51
Excessive pain during medical procedures, such as burn wound dressing changes, is a widespread medical problem and is especially challenging for children. This article describes the rationale behind virtual reality (VR) pain distraction, a new non-pharmacologic adjunctive analgesia, and gives a brief summary of empirical studies exploring whether VR reduces clinical procedural pain. Results indicate that patients using VR during painful medical procedures report large reductions in subjective pain. A neuroimaging study measuring the neural correlates of VR analgesia is described in detail. This functional magnetic resonance imaging pain study in healthy volunteers shows that the large drops in subjective pain ratings during VR are accompanied by large drops in pain-related brain activity. Together the clinical and laboratory studies provide converging evidence that VR distraction is a promising new non-pharmacologic pain control technique. 相似文献
873.
874.
The authors explore the division of labor between the basal ganglia-dopamine (BG-DA) system and the orbitofrontal cortex (OFC) in decision making. They show that a primitive neural network model of the BG-DA system slowly learns to make decisions on the basis of the relative probability of rewards but is not as sensitive to (a) recency or (b) the value of specific rewards. An augmented model that explores BG-OFC interactions is more successful at estimating the true expected value of decisions and is faster at switching behavior when reinforcement contingencies change. In the augmented model, OFC areas exert top-down control on the BG and premotor areas by representing reinforcement magnitudes in working memory. The model successfully captures patterns of behavior resulting from OFC damage in decision making, reversal learning, and devaluation paradigms and makes additional predictions for the underlying source of these deficits. 相似文献
875.
Previous research on the allocation of scarce resources suggests that people who are assigned to higher positions (e.g., leaders) are more likely to make self-benefiting allocations than people who are assigned to lower positions (e.g., followers). In this article, the authors investigated the proposition that these findings would be moderated by people's social value orientations. In two experimental studies, the authors assigned participants either to the role of leader or follower and assessed the participants' social value orientations. In agreement with predictions, the findings show that position effects are moderated by social value orientation. Social value orientations only affected the allocation behavior of the leaders: Proself leaders allocated more resources to themselves than did prosocial leaders. Additional analyses indicate that these effects are mediated by feelings of entitlement. 相似文献
876.
This meta-analytic review summarizes obesity prevention programs and their effects and investigates participant, intervention, delivery, and design features associated with larger effects. A literature search identified 64 prevention programs seeking to produce weight gain prevention effects, of which 21% produced significant prevention effects that were typically pre- to post effects. Larger effects emerged for programs that targeted children and adolescents (vs. preadolescents) and females, programs that were relatively brief, programs that solely targeted weight control versus other health behaviors (e.g., smoking), programs evaluated in pilot trials, and programs wherein participants must have self-selected into the intervention. Other factors, including mandated improvements in diet and exercise, sedentary behavior reduction, delivery by trained interventionists, and parental involvement, were not associated with significantly larger effects. 相似文献
877.
The association of total study time, number of events, time per event ratio, study strategies, and course grades across the semester were examined by linking students' study logs to course performance. There were 37 upper-division and 109 lower-division participants. Students earning As and Bs studied more frequently at the end of the semester but for shorter periods of time than students earning lower grades. Results are discussed in terms of providing college students and faculty with recommendations about learning strategies and time spent studying. 相似文献
878.
Suicide-related behavior (SRB), including suicide attempts and instrumental SRB, occurs far more often than completed suicide and exacts a toll on patients, their loved ones, and society. Nevertheless, few prospective studies of SRB have been conducted. In this study, 954 patients were interviewed in a psychiatric hospital and then followed for one year after discharge. During this one-year period, nearly one-quarter of patients (23%) engaged in SRB, with the rate of suicide attempts (18%) three times greater than the rate of instrumental SRB (5%). Risk factors for SRB were demographic (White ethnicity, female gender), clinical (past SRB, depression, impaired functioning), and contextual (unemployment, large social networks). In contrast with other studies, there was no "peak" in the risk of SRB shortly after hospital discharge. Instead, patients' rate of SRB was relatively constant over the one-year follow-up. Implications for risk assessment and management in acute inpatient settings are discussed. 相似文献
879.
Among the provisions of the recently signed Garrett Lee Smith Memorial Act, Congress called for the use of screening to detect adolescents who are at risk for suicide. After a review of the literature, 17 studies involving screening instruments and programs were identified. We addressed the question: What do we know about the demonstrated effectiveness and safety of screening as a tool or program to prevent suicide among adolescents? While youth suicide screening programs offer the promise of improving identification for those who need treatment the most, further research is essential to understand how, when, where, and for whom screening programs can be used effectively and efficiently. 相似文献
880.
Practice can dramatically reduce dual-task interference, but typically does not eliminate interference entirely. Residual interference after practice is especially large with certain non-preferred modality pairings (e.g., auditory–manual and visual–vocal). Does this residual interference imply the existence of a persistent central-processing bottleneck? To address this question, we transferred participants with previous dual-task practice to a psychological refractory period design. Although we observed residual dual-task costs in all four experiments, there was no evidence for a bottleneck, even with non-preferred modality pairings. We conclude that practice can eliminate the bottleneck limitation, but performance is still subject to other sources of interference, such as competition between central codes of the two tasks. 相似文献