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981.
An experiment which employed each of 18 subjects in four days of testing was used to examine acute secobarbital dose treatment effects on choice reaction time in a Cooper and Shepard (1973) character recognition task. Manipulations of visual stimulus degradation, character difficulty, 180 degree rotation, and mirror-image reversal were included in order to evaluate the hypothesis that the drug affects performance by disrupting early stimulus input processing. The results indicate significant increases in the effect of secobarbital on reaction time and errors under conditions of visual stimulus degradation. The effects of the drug, however, were not changed by 180 degree rotation of the target character or by the other task variables. The results were interpreted to indicate that secobarbital impairs performance primarily by placing selective stress on hypothetical early encoding activities and that later processing operations (associated with use of an internal representation of the target character) are not affected by the drug. Strengths and weaknesses of the two-stage model of visual stimulus processing are discussed and implications of the model for future drug research are indicated.  相似文献   
982.
The relationship between the availability of visual information and attention demands during the production of a discrete motor act was examined. Subjects were required to move a linear slide a distance of 15 cm in both 150 and 600 msec conditions under three light manipulations, viz., light always on; light always terminated as movement began; or, subject was unsure as to whether light would stay on or terminate. A simple key press by the index finger of the opposite hand to a tone was used as a secondary task and a measure of attention demands. The light manipulation influenced attention demands on the rapid 150 msec movement such that more attention was demanded when the subject knew the light would terminate. No such attentional strategy differences were found with the slow 600 msec movement. These findings suggest that task constraints in the form of kinematic criteria, together with the perceived availability of visual information, contribute to determining attentional strategy in movement production.  相似文献   
983.
Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings.  相似文献   
984.
985.
986.
This study reports the results of an investigation of the assessment views and practices of school psychologists in the United States. Results of the investigation indicated that respondents are predominantly behavioral and cognitive behavioral in orientation; spend most of their professional time in the public schools; and engage in a great deal of assessment. Behavioral assessment and projective testing occupies the greatest amount of their social-emotional assessment time. Behavioral interviewing is the most used behavioral technique, followed by behavioral observation, which is reportedly used by approximately one third of the respondents with from 41% to 100% of clients. Although most of the respondents report a preference for continuing to do approximately the same amount of the various social-emotional assessment activities as they are presently doing, very high percentages of respondents indicate that their use of behavioral assessment strategies would increase with development of published instrumentation, normative standards, and standardized out-of-setting behavioral procedures.  相似文献   
987.
Transfer of matching-to-figure samples in the pigeon   总被引:2,自引:1,他引:1       下载免费PDF全文
Three pigeons were trained on a modified six-key matching-to-sample procedure. The third peck on the figure-sample key (which presented a bird, hand, face, beetle, rabbit, fish, flower, or red hue, as the sample) lighted only one comparison key. Every three additional pecks on the sample lighted another comparison key, up to a maximum of five keys. Pecks on keys of matching figures produced grain. Pecks on nonmatching keys (mismatches) turned off all lights on the comparison keys and repeated the trial. Three figures were used during acquisition. The birds learned to peck each sample until the matching comparison stimulus appeared on one of three comparison stimulus keys, and then to peck that key. Later, five novel stimuli, employed as both sample and comparison stimuli, and two additional matching keys were added. Each bird showed matching transfer to the novel samples. The data suggest that the birds may have learned the concept of figure matching rather than a series of two-component chains or discrete five-key discriminations.  相似文献   
988.
Rats' lever pressing produced sucrose reinforcers on a variable-interval schedule where, in different conditions, the duration of a stimulus presented immediately after reinforcement was either correlated or uncorrelated with the duration of the current interreinforcement interval. Under the baseline schedule, in which no stimulus was presented, the minimum interreinforcement interval was 8 s and the mean postreinforcement pause of each subject approximated this value. Response rates increased slowly over the first 10 to 15 s and then remained roughly constant throughout the remainder of the interval. In both the correlated and uncorrelated conditions, the added stimulus resulted in the postreinforcement pauses lengthening to values in excess of the duration of the preceding stimulus. This resulted in a poststimulus pause which was, in most cases, roughly constant irrespective of the duration of the preceding stimulus, or of the reinforcement contingencies prevailing immediately after stimulus offset. Local response-rate patterns in the uncorrelated conditions were similar to those obtained under the baseline schedule in which no stimulus was presented. However, in the correlated condition local response rates increased across the remainder of the interreinforcer interval. Further, the rate of acceleration was inversely related to the duration of the preceding stimulus. These results show that a correlation between stimulus duration and the ensuing time to reinforcement can control behavior—a type of temporal control not previously reported.  相似文献   
989.
This paper reports the development and assessment of midi-level behavioral measures of social anxiety in the context of two experiments, one studying an analog student sample, the other a psychiatric sample. Judgments on nine categories of clinically practical midi-level behaviors (e.g. Facial Expression, Orienting, Sense of Timing), based on a review of the literature on human ethology and on pilot research, were compared to global judgments of social anxiety and social skill and to physiological arousal. Intraclass correlations exceeded 0.80 for judgments of the global and midi-level behavioral ratings on both samples. Results of correlational analyses indicated that while there were several significant predictors of global skill and anxiety among the midis, the magnitude of the relationship between midis and globals was stronger for the patient than the student sample. Further analyses based on S's heart rate (HR) reactivity suggested that while global ratings did not significantly predict H R in a high social anxiety situation, one midi-level behavioral rating (self-manipulations) did. The clinical utility of the newly developed measures is discussed with particular attention to their practicality for behavior therapy.  相似文献   
990.
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