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831.
Research has indicated that random physical practice of a motor skill enhances effects of long-term learning more than blocked practice. Moreover, the use of mental rehearsal coupled with physical practice has been shown to accelerate motor skill acquisition in many different contexts and is better than no practice at all. Others have found that some mental rehearsal strategies are better than others for maximizing performance. This study examined how combinations of mental and physical practice schedules affected the learning of a coincidence timing task. 30 college students were randomly assigned to one of four treatment groups involving combinations of imagery and physical practice. Three tasks were utilized, each involving a particular speed (slow, medium, fast) on the Bassin Anticipation Timer. Conclusions were based on a three-way analysis of variance, using type of mental practice, type of physical practice, and sex as between-group factors, conducted separately for acquisition and retention trials. Type of physical practice was significantly related to performance. On the acquisition trials, random practice was associated with larger mean errors than blocked practice; however, the reverse was true for retention trials. There was no significant effect of type of mental practice in either the acquisition or retention phase. Sex was significantly related to performance for the retention trials only, where the 15 men made smaller errors than the 15 women. 相似文献
832.
Ehrlich R 《The Psychoanalytic quarterly》2004,73(2):453-484
The author suggests that, although Donald Winnicott presented some important criticisms of Melanie Klein's work, at times he tried to advance his perspectives too definitively without adequately considering her own. Because of this, he failed to acknowledge sufficiently that he was offering a model of human nature and development that could be revised. The fact that his differences with Klein arose in the context of a complex relationship in which each played numerous roles for the other, especially in the context of their affiliation with the British Psychoanalytical Society, periodically made it difficult for him to present his ideas more carefully and in his more characteristically open manner. 相似文献
833.
Throughout the U.S., state laws require professionals who work with children to report cases of suspected child abuse to child protection services. Both practically and conceptually, however, significant problems arise from a lack of clarity regarding the threshold that has been set for reporting. Specifically, there is no consensus as to what constitutes reasonable suspicion, and little direction for how mandated reporters should gauge their legal and professional responsibilities when they harbor suspicion. In this paper we outline the context of the problem, discuss the nature and scope of its conceptual underpinnings, and offer recommendations for moving towards a concrete, practical solution. 相似文献
834.
A total of 30 undergraduates recalled the same 20 autobiographical memories at two sessions separated by 2 weeks. At each session they dated their memories and rated them on 18 properties commonly studied in autobiographical memory experiments. Individuals showed moderate stability in their ratings on the 18 scales (r approximately .5), with consistency of dating being much higher (r = .96). There was more stability in the individuals' average rating on each scale (r approximately .8), even when the averages were calculated on different memories in the different sessions. The results are consistent with a constructive view of autobiographical memory, in which stable individual differences in cognitive style are important. 相似文献
835.
Social disruption (SDR) is an effective model of social stress associated with an enhanced inflammatory reactivity of the immune system. The aim of the present study was to further describe SDR effects on cytokine production by spleen cells, testing selectively monocyte and T cell functions as a result of this stressor. For this purpose, splenocytes from control mice (C) and mice socially stressed for 7 days (SDR) were cultured in the presence of lipopolysaccharide (LPS) or concanavalin A (Con A). Splenocyte proliferation, cytokine production and sensitivity of spleen cells to corticosterone were assessed in vitro. The humoral response to keyhole limpet hemocyanin (KLH) immunization was assessed. SDR induced splenomegaly and enhanced splenocyte basal proliferation. The pro-inflammatory influence of SDR was confirmed by an increased release of interleukin-6 (IL-6) by LPS-stimulated cultures and by a reduced sensitivity of spleen cells to the anti-inflammatory effect of corticosterone. The mechanism increasing cytokine production in response to LPS was cytokine specific, since among inflammatory cytokines, IL-6 but not interferon-gamma (IFN-gamma) was enhanced by stress. In stressed mice, the increase in IL-6 and IFN-gamma and the decrease in IL-10 release in Con A-stimulated cultures indicate that SDR did not modify the Th1/Th2 cytokine balance but globally activated T cells. Plasma anti-KLH antibody levels were similar in both groups. Wounded and non-wounded mice presented similar responses to stress. This study shows that social disruption stress enhances the reactivity of cells from both the acquired and innate immune systems. 相似文献
836.
We have developed an experimental platform that allows a large number of human participants to interact in real time within a common virtual world. Within this environment, human participants foraged for resources distributed in two spatially separated pools. In addition to varying the relative replenishment rate for the two pools (50-50, 65-35, or 80-20), we manipulated whether the participants could see each other and the entire resource distribution or had their vision restricted to resources at their own location. Two empirical deviations from an optimal distribution of the participants were found. First, the participants were more scattered within a resource pool than the resources were themselves. Second, there was systematic underutilization of the richer pool. For example, the participants distributed themselves 73% and 27% to resource pools that had replenishment rates of 80% and 20%, respectively. In addition, there were oscillations in the harvesting rate of the pools across time, revealed by a Fourier analysis with prominent power near 50 sec per cycle. The suboptimalities and oscillations were more apparent when the locations of the participants and the food were not visible. Individual participant knowledge thus affects the efficiency with which a population of participants harvests resources. 相似文献
837.
Cohen MR Meissner GW Schafer RJ Raymond JL 《Learning & memory (Cold Spring Harbor, N.Y.)》2004,11(5):559-565
Motor learning in the vestibulo-ocular reflex (VOR) and eyeblink conditioning use similar neural circuitry, and they may use similar cellular plasticity mechanisms. Classically conditioned eyeblink responses undergo extinction after prolonged exposure to the conditioned stimulus in the absence of the unconditioned stimulus. We investigated the possibility that a process similar to extinction may reverse learned changes in the VOR. We induced a learned alteration of the VOR response in rhesus monkeys using magnifying or miniaturizing goggles, which caused head movements to be accompanied by visual image motion. After learning, head movements in the absence of visual stimulation caused a loss of the learned eye movement response. When the learned gain was low, this reversal of learning occurred only when head movements were delivered, and not when the head was held stationary in the absence of visual input, suggesting that this reversal is mediated by an active, extinction-like process. 相似文献
838.
McNulty, Harkness, Ben-Porath and Williams recently developed Personality Psychopathology Five (PSY-5) scales for the Minnesota Multiphasic Personality Inventory-A (MMPI-A). This study examined these new scales in a sample of 545 adolescents receiving inpatient psychiatric treatment. Item-level principal components analyses were employed to determine the internal structure of each PSY-5 scale and to aid in the creation of facet subscales for each PSY-5 scale. Results suggest that the MMPI-A PSY-5 scales display adequate internal consistency and our findings generally replicate the original work of McNulty et al. but also extend this work by showing that several of the PSY-5 scales may also be subdivided into meaningful lower level dimensions. These facet subscales for each of the MMPI-A PSY-5 scales are offered for further study. 相似文献
839.
There is a high prevalence of psychological disorders among adolescents in detention facilities. The need for a simple, effective screening tool led to the development of the Massachusetts Youth Screening Instrument (MAYSI) and its successor, the MAYSI-2. This study evaluated the MAYSI-2 psychometric properties based on the records of 704 youths evaluated at intake to detention facilities. In addition to factor structure, the study evaluated test-retest reliability and concurrent external validity. Results were generally encouraging in terms of the use of MAYSI-2 in detention facilities, and directions for future research are discussed. 相似文献
840.
The lexically based Five-Factor Personality Inventory (FFPI) was correlated with the factors and facets of the Revised NEO Personality Inventory (NEO-PI-R) in Belgian (N = 265), American (N = 116), and Hungarian (N = 320) samples. Results were similar across the three cultures. Analysis of orthogonalized FFPI factors showed that three of them--emotional stability, extraversion, and agreeableness--showed a direct correspondence to their NEO-PI-R counterparts. Autonomy, however, was not clearly related to openness, and facet analysis suggested that it might be interpreted as a dominance factor Better matches to NEO-PI-R conscientiousness and openness could be obtained by using vectors rotated 30 degrees from the FFPI positions. Raw scale scores showed similar results. Researchers should not assume that all measures of the Five-Factor Model are qualitatively similar 相似文献