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891.
A new group-training procedure for habituation demonstrates that presynaptic glutamate release contributes to long-term memory in Caenorhabditis elegans 总被引:2,自引:0,他引:2 下载免费PDF全文
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
892.
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
893.
894.
Nersesyan AK 《Science and engineering ethics》2002,8(3):291-293
The author describes problems facing Armenia in reorganization of the structure of science in the post-socialist era with
the aim of utilizing limited state resources more efficiently by reducing the number of separate scientific institutes, concentrating
on essential core subjects required by the nation and encouraging all other projects to compete in the international arena
for grant sponsorship.
An earlier version of this paper was presented at an International Conference on “Conflict of Interest and its Significance
in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002. 相似文献
895.
Nieuwenhuis S Ridderinkhof KR Talsma D Coles MG Holroyd CB Kok A van der Molen MW 《Cognitive, affective & behavioral neuroscience》2002,2(1):19-36
When participants commit errors or receive feedback signaling that they have made an error, a negative brain potential is elicited. According to Holroyd and Coles’s (in press) neurocomputational model of error processing, this error-related negativity (ERN) is elicited when the brain first detects that the consequences of an action are worse than expected. To study age-related changes in error processing, we obtained performance and ERN measures of younger and high-functioning older adults. Experiment 1 demonstrated reduced ERN amplitudes in older adults in the context of otherwise intact brain potentials. This result could not be attributed to uncertainty about the required response in older adults. Experiment 2 revealed impaired performance and reduced response- and feedback-related ERNs of older adults in a probabilistic learning task. These age changes could be simulated by manipulation of a single parameter of the neurocomputational model, this manipulation corresponding to weakened phasic activity of the mesencephalic dopamine system. 相似文献
896.
897.
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
898.
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
899.
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
900.
Ulman KH 《International journal of group psychotherapy》2000,50(3):341-362
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