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971.

Authors Index

List of Contributors  相似文献   
972.
Affective priming of aggression was examined in groups low and high in trait negative emotionality (NEM) using a Buss aggression paradigm. Negative affect was induced by exposure to aversive air blasts during some intervals (threat) and not others (safe). Phasic negative affect was assessed using startle reflex potentiation, and tonic distress was indexed by startle sensitization. Participants delivered shocks faster during threat versus safe intervals, indicating that phasic distress primed aggression. Following initial exposure to air blasts, high NEM participants showed enhanced tonic distress and delivered persistently more intense shocks than low NEM participants. These findings indicate that sustained negative affect biases high stress-reactive individuals toward more intense acts of aggression, with phasic distress affecting the rapidity of aggressive response.  相似文献   
973.
Functional magnetic resonance imaging (fMRI) is used to study brain function during behavioral tasks. The participation of pediatric subjects is problematic because reliable task performance and control of head movement are simultaneously required. Differential reinforcement decreased head motion and improved vigilance task performance in 4 children (2 with behavioral disorders) undergoing simulated fMRI scans. Results show that behavior analysis techniques can improve child cooperation during fMRI procedures.  相似文献   
974.
In 2 studies, the antecedents and consequences of "principled objections" to affirmative action (specific, "race-neutral" reasons for opposing the policy) among Whites were examined. In Study 1. data from a probability sample of Los Angeles adults indicated the following: (a) that principled-objection endorsement was driven not merely by race-neutral values but also by dominance-related concerns like racism; (b) that principled objections mediated the effects of group dominance; and (c) that education strengthened-rather than attenuated-the relationship between dominance-related concerns and principled objections. whereas it left the relationship between race-neutral values and the latter essentially unchanged. In Study 2, the education findings were conceptually replicated in a panel study of undergraduates: The completion of additional years of college boosted the correlation between racism and principled objections, whereas it had no effect on the predictive power of conservatism. These results provide support for a general group-dominance approach, which suggests that factors like racism continue to shape White opposition to race-targeted policies.  相似文献   
975.
A new contraceptive technology may advance the science of family planning but may do little to affect health if potential users do not deem it an acceptable method. The authors conducted an acceptability study of a newly developed contraceptive method--personal hormone monitoring. A sample of 480 English volunteers present at the 6th month of a 13-month longitudinal study completed surveys regarding their attitudes toward a personal hormone monitor for the purpose of contraception. The authors used the participants' responses to determine (a) the extent to which the participants accepted the monitor, (b) how their ratings of acceptability changed over time, (c) the extent to which contextual variables predicted changes in acceptability over time, and (d) whether those contextual variables predicted final acceptability of the monitor. Results suggested that no single method of family planning is best for everyone and specified the people for whom personal hormone monitoring may be most suitable.  相似文献   
976.
A sample of 157 Korean immigrants responded to measures of acculturation level, stress from acculturation, and depressive symptoms. The authors hypothesized that adaptive acculturation would depend on assimilation regarding social interactions and the host culture's language as well as on retention of a core identity, including values and traditions of the culture of origin. Consistent with the mediation hypothesis, acculturation, based on a factor representing language use and social relationships, was related to lower acculturative stress and, in turn, lower depression. However, there was no direct support for the integrative, or bicultural, strategy of acculturation. Stress did not mediate the effect of a 2nd acculturation factor, identity and tradition-based acculturation. Rather, this measure of acculturation was directly related to higher depression (i.e., immigrants reporting abandonment of Korean identity, traditions, and values scored higher for depression).  相似文献   
977.
31 college age men and women who consume less than three caffeinated beverages per week agreed to participate as subjects in research on the effects of acute caffeine intake on low intensity task performance. All subjects performed two randomly administered test conditions: (1) caffeine (5 mg/kg) and (2) placebo on separate visits following an initial 1-hr. orientation visit. Subjects were administered the beverage 30 min. prior to performing 12 separate tests assessing basic mathematics, simple response, logical reasoning, hand-eye coordination, and spatial and assembly skills. The Spielberger State Anxiety test was administered immediately after consuming the test beverage and once again at posttest. Analysis showed that caffeine did not significantly affect performance on all tests with the exception of the peripheral awareness (hand-eye coordination) test on which performance was higher after ingesting caffeine. The placebo treatment produced no effect on state anxiety, which contrasted with a significant rise in anxiety after caffeine consumption. State anxiety values were significantly greater after caffeine treatment relative to the placebo at pretest, and this difference persisted at posttest. These results demonstrated that the dose of caffeine increased scores on state anxiety for individuals who consumed less than three caffeinated beverages weekly but had very little effect on performance of low intensity tasks, except for a hand-eye coordination test involving peripheral awareness. Perhaps longer continuous performance of more demanding tasks would be more sensitive.  相似文献   
978.
In karate, performance also depends on a correct body shape, and the repeatability of standardized movements conditions the effectiveness of techniques. The execution of mae-geri-keage (frontal snap kick) was studied in 13 karateka (1st-5th dan). The 3D trajectories of 13 body landmarks were analyzed by an optoelectronic instrument while each karateka performed 10 repetitions of the movement. For each karateka and repetition, the standard deviations of the spatial coordinates x, y, z for each landmark were computed. A total standard deviation of the single participant was also calculated. Two experienced karateka performed with the best repeatability (smaller standard deviation) while executing the studied kick. Generally, the best repeatability was observed in the horizontal plane. The lower variability was observed in hips and head. Ankle and knee of the dominant limb had the worse. The method could detect athletes particularly gifted for the discipline. Moreover, it could help in the identification of those parts of body that do not repeat the movement with the desired precision.  相似文献   
979.
There is increasing evidence that the behavior of living systems can be conceptualized as a self-organizing dynamical system. Moreover, evidence suggests that inhibitory processes give these systems the flexibility that is necessary for efficient functioning in the face of changing environmental demands. The process of sensitization can be conceived as a breakdown of inhibitory neural processes that can lead to maladaptive, perseverative behavior. In this paper we describe a model of inhibition and sensitization from a dynamical systems perspective. We show that inhibition is important for adaptive behavior across a number of levels of system functioning. Using our work on attention, emotion, and anxiety disorders we show the importance of both central - for example gamma-aminobutyric acid (GABA)-ergic - and peripheral - for example heart rate variability (HRV) - inhibitory processes and how they may be linked by a network of neural structures that guide the organism from one state of relative stability to another.  相似文献   
980.
The present study investigated the effects of multiple trauma exposure and coping style on post-traumatic stress symptoms and quality of life. It was hypothesized that sensitization would occur in subjects repeatedly exposed to life-threatening situations (study 1), and different coping styles would act as a resilience or facilitating factor in symptom development (study 2). The results showed that the single-exposure group revealed a decrease in trauma specific stress reactions from three weeks to four months, with a persistent reduction at 12-month follow-up, while the repeated-exposure group showed an increase in symptom reporting over the 12-month period. The same pattern emerged for perceived quality of life-measured by the General Health Questionnaire (GHQ-30). The second study revealed a correlation between scores on avoidant-focused coping style and the Impact of Event Scale-avoidance dimension, Post-traumatic Symptom Scale and GHQ-30. Furthermore, only subjects with a dominant coping style of emotion-focused or task-focused coping showed a reduction in trauma-specific symptom scores over time.  相似文献   
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