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101.
102.
How is attention distributed over visual space when an observer expects a target to occur at one of several possible locations? Two experiments sought to understand the source of the conflict between studies leading to the notions of hemifield activation (Hughes and Zimba 1985) and attentional gradients (Downing and Pinker 1985; Shulman et al. 1985, 1986). Subjects were cued to attend one of the 4 corners of an imaginary square centered at fixation, allowing comparison of uncued locations in the cued and uncued hemifields. In one experiment marking of the 4 locations was varied to determine if providing a ‘target’ for attention is necessary to obtain within-hemifield gradients. RT was faster at the cued location than at the three uncued locations which had equivalent latencies, a pattern that was unaffected by marking of the potential target locations. This result, which is consistent with the notion of a gradient around the attended location is a strong disconfirmation of the hemifield activation hypothesis. The second experiment demonstrated that an unusual procedure for presenting the probe stimuli in Hughes and Zimba (1985) is at least partially responsible for their evidence for uniform hemifield activation. It is proposed that visual attention is directed to visuo-spatial channels with fixed structural properties, and that when attention to two locations is desired, the subject may attend a spatial channel located between them.  相似文献   
103.
The purpose of this study was to compare our structured research-based version of marital therapy from a social learning perspective with a clinically flexible version of the same treatment where treatment plans were individually-based and there was no specific number of treatment sessions. Thirty distressed married couples were randomly assigned to one of these two treatments. Assessment of outcome was based on global marital satisfaction, spouse reports of functioning in specific areas, and direct observational measures of communication. At posttest there were no differences in efficacy between structured and flexible treatments, although both treatments led to significant improvements. At a 6-month follow-up couples treated with the structured format were more likely to have deteriorated and flexibly treated couples were more likely to have maintained their treatment gains.  相似文献   
104.
The field of infant perceptual development has relied heavily on the preferential-looking and habituation paradigms. Despite the obvious advantages of employing standardized methodologies, there is a need to study how perceptual variables give rise to and guide action beginning in the neonatal period. It is argued here that, in the first 5 months of life, it is important to distinguish reflexive patterns of movement from voluntary and cortically controlled patterns. Some criteria are defined. This paper describes three experiments which utilized movement counters to record developmental changes in the frequency and synchrony of limb movements in infants under 5 months. The results show that there is a general increase in frequency of limb movements from 1 to 5 months, but with a plateau or even a decrease in activity from the middle of the third month to the end of the fourth month. It was also demonstrated that synchrony scores (co-activation) for pairs of limbs showed significant increases from 1 month to 5 months. Finally, in all three experiments the presentation of an attractive toy resulted in suppression of activity. The results of the three experiments are interpreted to measure a gradual increase in cortically controlled movement patterns.  相似文献   
105.
Although there has been a considerable amount of research on simultaneous and successive processing (Luria's second functional unit) by Das and others, there have been relatively few investigations into the measurement of attention and planning (the first and third functional units, respectively). The purpose of this investigation was to examine the factorial validity of tasks designed to measure cognitive processing in each of Luria's three functional units. A sample of 112 normal fourth- and fifth-grade students were administered nine experimental tasks chosen or developed according to the theoretical components of planning, attention, simultaneous, and successive processes. Principal factor analyses (orthogonal and oblique) with rotation of four factors resulted in solutions that closely matched the anticipated groupings based on a structural analysis of the tasks. General support for the feasibility of measurement of Luria's cognitive processing model, and the need to further develop and refine these and other experimental tasks, was obtained.  相似文献   
106.
Topographic electroencephalographic alpha in recovered depressed elderly   总被引:1,自引:0,他引:1  
Late-middle-aged and elderly normal volunteers with past histories of Major Depression according to the Diagnostic and Statistical Manual of Mental Disorders (third edition-revised) criteria were compared with sex- and age-matched control subjects using topographic electroencephalographic (EEG) indices. Healthy, euthymic recovered depressed subjects showed greater alpha amplitudes than controls. Delta, theta, and beta amplitudes did not reliably distinguish the groups. Considered in the context of previous research indicating that actively depressed subjects exhibit elevated EEG alpha compared to controls, these findings raise questions concerning state and trait conceptualizations of depression and EEG alpha.  相似文献   
107.
Twenty-eight boys and 28 girls at each of the Piagetian preoperational, concrete operational, and formal operational cognitive stages were given an interview focusing on their concepts of family. Half of each group were from intact families, and half were from divorced families. Interviews were scored for two structural aspects of the concept of family: conceptual level, and use of dimensions that structure the concept. The complexity of children's concepts was strongly related to cognitive stage and, to a lesser degree, to sex. Frequency of use of concept dimensions was strongly affected by general developmental level, though not specifically cognitive stage, and by intactness of family, but to a lesser degree by sex. Specific information is provided on the effect of these factors on perceptions of family composition, parental roles, and breadth of family activities.  相似文献   
108.
The present study simulated an organizational dispute to test 12 hypotheses about mediator behavior that were derived from the strategic choice model of mediation. This model is based on the assumption that mediators have four basic strategies to resolve disputes: (a) integrate, which involves a search for mutually acceptable outcomes; (b) press, which involves lowering one or both parties' aspirations; (c) compensate, which involves offering positive benefits in exchange for concessions; and (d) inaction, which involves letting the parties handle the dispute by themselves. The major proposition of the model is that two factors, the mediator's assessment of the likelihood of a mutually acceptable agreement and the mediator's concern for the parties' aspirations, interact to predict mediator behavior. Nine of the 12 hypotheses derived from the model were supported. Pressing by mediators occurred most when mediators had a low estimate of the likelihood of agreement in combination with a low concern for the parties' aspirations. Compensating occurred most when mediators had a low estimate of the likelihood of agreement in combination with a high concern for the parties' aspirations. Inaction occurred most when the mediators' estimate of the likelihood of agreement was high and their concern for the parties' aspirations was low. Integrating occurred most when the mediators had a high concern for the parties' aspirations.  相似文献   
109.
Previous researchers using between-subjects comparisons have found eyewitness confidence and accuracy to be only negligibly correlated. In this study, we examined the predictive power of confidence in within-subject terms. Ninety-six subjects answered, and made confidence ratings for, a series of questions about a crime they witnessed. The average between-subjects and within-subject accuracy-confidence correlations were comparably low: r = .14 (p less than .001) and r = .17 (p less than .001), respectively. Confidence is neither a useful predictor of the accuracy of a particular witness nor of the accuracy of particular statements made by the same witness. Another possible predictor of accuracy, response latency, correlated only negligibly with accuracy (r = -.09 within subjects), but more strongly with confidence (r = -.27 within subjects). This pattern was obtained for both between-subjects and within-subject comparisons. The theoretical and practical implications of these results are discussed.  相似文献   
110.
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