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991.
Effect of click rate and delay on breakdown of the precedence effect   总被引:1,自引:0,他引:1  
The precedence effect was tested as a function of echo-click delay and click rate after an abrupt switch in location between leading and lagging clicks. Click trains at three rates, 1/sec, 2/sec, and 4/sec, with delays ranging between 2 and 20 msec, were presented to subjects in an anechoic chamber. Duration of the click train after the switch in location was 12 sec, and echo click perceptibility was assessed throughout this period. The number of echo clicks heard was an increasing monotonic function of delay. The subjects reported a "fade-out" of echo clicks after a set number of clicks at each delay, regardless of rate. This result was interpreted as a buildup in inhibition of echoes produced by the ongoing click train. Suppression of echoes was stronger when the leading click originated from the right side than from the left side.  相似文献   
992.
993.
The incidence of secondary enuresis in 16 institutionalized conduct-disordered children was examined. In contrast to a control group of 16 noninstitutionalized conduct-disordered children, the former showed significantly more enuretic behaviour. Also, enuresis began within 6 mo. of the children's separation from their families, suggesting this problem is very likely related to the emotional trauma surrounding the change in living conditions. However, the small number of subjects limits further interpretation of the findings.  相似文献   
994.
An Extended Two-Way Euclidean Multidimensional Scaling (MDS) model which assumes both common and specific dimensions is described and contrasted with the standard (Two-Way) MDS model. In this Extended Two-Way Euclidean model then stimuli (or other objects) are assumed to be characterized by coordinates onR common dimensions. In addition each stimulus is assumed to have a dimension (or dimensions) specific to it alone. The overall distance between objecti and objectj then is defined as the square root of the ordinary squared Euclidean distance plus terms denoting the specificity of each object. The specificity,s j , can be thought of as the sum of squares of coordinates on those dimensions specific to objecti, all of which have nonzero coordinatesonly for objecti. (In practice, we may think of there being just one such specific dimension for each object, as this situation is mathematically indistinguishable from the case in which there are more than one.)We further assume that ij =F(d ij ) +e ij where ij is the proximity value (e.g., similarity or dissimilarity) of objectsi andj,d ij is the extended Euclidean distance defined above, whilee ij is an error term assumed i.i.d.N(0, 2).F is assumed either a linear function (in the metric case) or a monotone spline of specified form (in the quasi-nonmetric case). A numerical procedure alternating a modified Newton-Raphson algorithm with an algorithm for fitting an optimal monotone spline (or linear function) is used to secure maximum likelihood estimates of the paramstatistics) can be used to test hypotheses about the number of common dimensions, and/or the existence of specific (in addition toR common) dimensions.This approach is illustrated with applications to both artificial data and real data on judged similarity of nations.  相似文献   
995.
To assess temporal variations in the perception of "phasic" heat pain stimuli a psychophysical tracking procedure was developed that enables repeated assessment of the pain threshold at short intervals. This "double-tracking" procedure produces two tracking curves simultaneously, one that approaches the pain threshold gradually from above, the other from below. The threshold for phasic heat pain was measured in 80 tracking trials with stimuli at temperatures near the pain threshold. Concurrently, the threshold for "tonic" heat pain was determined after every 20 tracking trials with a stimulus adjustment procedure. Eleven healthy subjects (age: 26.4 yr. +/- 6.0) participated in 2 sessions each. Phasic stimulation near the pain threshold did not produce any trends in either of the two threshold measures. Hence there was no long-term adaptation or sensitization. However, there were random variations (random walks) in the tracking curves, which we interpret as resulting from a stochastic relationship between stimulus and sensation. In agreement with other reports, discrimination seemed to be better at painful than at nonpainful temperatures.  相似文献   
996.
The purpose of this study was to determine whether test anxiety could be significantly reduced through regular practice of relaxation exercises or physical exercise. Test anxiety was assessed at pretest and posttest using the 37-item true-false Test Anxiety Questionnaire developed by Sarason. 47 undergraduate students self-selected to participate. The 9 subjects in the group who engaged in a nonmeditative relaxation exercise 3 times per week for 7 weeks showed a significant decline in test anxiety. The 16 subjects in a supervised aerobic dance class 3 times per week for 7 weeks improved their fitness and their test anxiety significantly declined. The 20 control subjects did not meet over the 7-week study ahd showed no significant change in test anxiety, fitness, or relaxation.  相似文献   
997.
Dynamic attending and responses to time   总被引:6,自引:0,他引:6  
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998.
Cognitive change processes in psychotherapy   总被引:1,自引:0,他引:1  
Several types of cognitive-behavioral therapy are now practiced that use different sets of theoretical concepts and propose different kinds of change mechanisms. None, however, is directly grounded in experimental research in cognitive and social psychology, and few address basic issues such as the relevance of conscious versus nonconscious cognitive processes and the validity of the self-report data on which therapy depends. Put forward in this article is a model that describes the conscious and nonconscious processing of emotional stimuli and distinguishes between knowledge that is verbally accessible and knowledge that can only be recovered by exposure to situational cues. Also proposed are three mechanisms of cognitive change that involve altering verbally accessible knowledge, the accessibility of nonconscious situational memories, and self-regulatory strategies. These mechanisms are related to the current practices of behavioral and cognitive-behavioral therapists.  相似文献   
999.
This paper describes the use of concurrent individual and conjoint sessions in couples psychotherapy. The introduction of these individual interviews is seen as supporting the individual changes which must be made to effect change in the structure of the relationship. The benefits of this interventive scheme in dynamically oriented couples' treatment will be illustrated through the presentation of case examples.  相似文献   
1000.
Thirty-five families completed ratings describing their perceptions of their therapists. These ratings were then correlated with measures of outcome to assess whether there was a relationship between experiences of the therapist and treatment outcome. Further, the study addresses whether some family members' perceptions are more influential in affecting the course of treatment. The results showed that family members' perception of the therapist does have an impact on treatment outcome, but not all members affect the outcome equally. Further results and their implications are discussed.  相似文献   
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