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961.
In the experiments reported here we have developed a new group-training protocol for assessing long-term memory for habituation in Caenorhabditis elegans. We have replicated all of the major findings of the original single-worm protocol using the new protocol: (1) distributed training produced long-term retention of training, massed training did not; (2) distributed training at long interstimulus intervals (ISIs) produced long-term retention, short ISIs did not; and (3) long-term memory for distributed training is protein synthesis-dependent as it could be blocked by heat shock during the inter-block interval. In addition, we have shown that long-term memory for habituation is graded, depending on the number of blocks of stimuli in training. The inter-block interval must be >40 min for long-term retention of training to occur. Finally, we have tested long-term memory for habituation training in a strain of worms with a mutation in a vesicular glutamate transporter in the sensory neurons that transduce tap (eat-4). The results from these eat-4 worms indicate that glutamate release from the sensory neurons has an important role in the formation of long-term memory for habituation.  相似文献   
962.
Twenty-four adults (24 to 53 years old) with Attention-Deficit/Hyperactivity Disorder (ADHD), Combined Type, were studied in a double-blind, placebo-controlled, crossover study of Pycnogenol and methylphenidate. Pycnogenol is an antioxidant derived from the bark of the French maritime pine tree. Methylphenidate is a standard pharmaceutical intervention for ADHD. Anecdotal reports suggest that Pycnogenol improves concentration in adults with ADHD without adverse side effects. Participants received Pycnogenol, methylphenidate, and placebo, each for three weeks, in a randomized and counterbalanced order. Although ADHD symptoms improved during treatment, neither methylphenidate nor Pycnogenol outperformed the placebo control, as measured by self-report rating scales, rating scales completed by the individual's significant other, and a computerized continuous performance test. The conservative dosage levels and relatively brief length of treatment may have contributed to the absence of significant differences among treatment conditions. Implications for future research are noted.  相似文献   
963.
964.
965.
The purpose of the current study was to determine whether a standardized peer entry paradigm would produce stress responses in 3- and 4-year-olds and how such stress responses would relate to temperament, observed approach to peers, and self-perceived peer competence. Physiological stress reactions were measured by activity of the hypothalamic-pituitary-adrenal (HPA) system. The 4-year-old group showed significantly less avoidance of the new peers and was rated higher on approach temperament. This older group also showed larger HPA stress responses to the new peer situation. Finally, discrepancy between self-reported peer competence and behavior in the peer entry situation was associated with larger stress responses on average. These findings support the notion that investment in a salient episode plays a role in determining the magnitude of HPA stress responses. The importance of examining discrepancies between self-perception and action in research on stress is discussed.  相似文献   
966.
The goal of this research was to examine the effect of jury deliberations on juror's propensity to disregard inadmissible evidence. Extant research is inconclusive; some research indicates that jurors do follow judicial instructions to ignore inadmissible evidence, but other research suggests that jurors do not. Two experiments examined whether jurors were affected by inadmissible evidence. The results revealed that although mock jurors were biased by inadmissible evidence prior to deliberations, the bias was tempered following deliberations. In Experiment 1, post deliberation jurors disregarded incriminating evidence that was ruled inadmissible because of due-process concerns. Experiment 2 replicated these results with less incriminating inadmissible evidence and also revealed that jurors did not accurately gauge the impact that the inadmissible evidence had on their verdicts. Theoretical and judicial policy implications are discussed.  相似文献   
967.
This study quantified the effects of 5 factors postulated to influence performance ratings: the ratee's general level of performance, the ratee's performance on a specific dimension, the rater's idiosyncratic rating tendencies, the rater's organizational perspective, and random measurement error. Two large data sets, consisting of managers (n = 2,350 and n = 2,142) who received developmental ratings on 3 performance dimensions from 7 raters (2 bosses, 2 peers, 2 subordinates, and self) were used. Results indicated that idiosyncratic rater effects (62% and 53%) accounted for over half of the rating variance in both data sets. The combined effects of general and dimensional ratee performance (21% and 25%) were less than half the size of the idiosyncratic rater effects. Small perspective-related effects were found in boss and subordinate ratings but not in peer ratings. Average random error effects in the 2 data sets were 11% and 18%.  相似文献   
968.
This article proposes an integrative model for stress management groups for women, representing a biopsychosocial point of view and drawing on theories of psychodynamic group psychotherapy, self-psychology, female development, and stress management. The basis of the model is an eight week traditional stress management group. The novel aspects of this integrative model are that it aims to increase the power of stress management groups for women by providing an articulated frame, attending to group process, promoting curiosity regarding resistance to behavior changes, encouraging the elaboration of affect, and giving importance to the role of relationships in each member's quest for self care and healthy entitlement.  相似文献   
969.
Bracing for loss     
People find unexpected bad news aversive and often brace themselves by predicting the worst. Three experiments examined whether the pessimism is influenced by personal need. Students who differed in financial need learned that a billing error meant that some students would receive an additional bill from their university. Financially needy students were consistently pessimistic in predicting their likelihood of receiving a bill, whereas non-needy students were not. In addition, the experiments reveal that (a) the pessimism occurred for potential losses but not potential gains, (b) needy students were pessimistic about their own chances but not the chances of a friend, (c) the pessimism was not attributable to needy students' being more readily primed by the news of a possible bill or to needy students' having more experience with billing errors, and (d) the pessimism was specific to monetary losses and did not generalize to other events.  相似文献   
970.
Two studies examined violent video game effects on aggression-related variables. Study 1 found that real-life violent video game play was positively related to aggressive behavior and delinquency. The relation was stronger for individuals who are characteristically aggressive and for men. Academic achievement was negatively related to overall amount of time spent playing video games. In Study 2, laboratory exposure to a graphically violent video game increased aggressive thoughts and behavior. In both studies, men had a more hostile view of the world than did women. The results from both studies are consistent with the General Affective Aggression Model, which predicts that exposure to violent video games will increase aggressive behavior in both the short term (e.g., laboratory aggression) and the long term (e.g., delinquency).  相似文献   
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