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911.
Experienced observers were asked to identify, in a four-level 2AFC situation, the longer of two unfilled time intervals, each of which was marked by a pair of 20-msec acoustic pulses. When all the markers were identical, high-level (186-dB SPL) bursts of coherently gated sinusoids or bursts of band-limited Gaussian noise, a change in the spectrum of the markers generally did not affect performance. On the other hand, for 1-kHz tone-burst markers, intensity decreases below 25 dB SL were accompanied by sizable deterioration of the discrimination performance, especially at short (25-msec) base intervals. Similarly large changes in performance were observed also when the two tonal markers of each interval were made very dissimilar from each other, either in frequency (frequency difference larger than 1 octave) or in intensity (level of the first marker at least 45 dB below the level of the second marker). Time-difference thresholds in these two latter cases were found to be nonmonotonically related to the base interval, the minima occurring between 40- and 80-msec onset separations.  相似文献   
912.
Reaction times were measured in a task which requires the subject to search a brief visual array for a critical letter embedded in a row of background letters. In Experiment 1, the position of a critical letter in an instructed reading order and the size of a set of memorized letters were varied. Mean reaction time increased monotonically with distance of the critical letter from the beginning of the instructed reading path in the display. The variables reading position and memory set size were additive in their effect on mean reaction time. Data from a second experiment in which the retinal location of the critical letter and its reading position were varied showed that both reading position and retinal location influenced mean reaction time, but the effect of reading position on reaction time was greater. These variables interacted.  相似文献   
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L B Feldman 《Family process》1976,15(4):389-395
A family-systems model of depression is presented and discussed. In this model, the intrapsychic concept of cognitive schema and the interpersonal concepts of social stimulation and social reingorcement are integrated within a systems-theory perspective. The effects of positive and negative feedback are delineated, and a concept of depression-triggering and depression-maintaining feedback loops is described. A clinical illustration is utilized to exemplify the theoretical model.  相似文献   
919.
This study examined differences in vocational maturity of women across different levels of internal-external control and typical versus atypical vocational choice. It was predicted that internally controlled women would have higher vocational maturity scores than externally controlled women; women who make atypical vocational choices would have higher vocational maturity scores than women who make typical choices. Data from the Attitude Scale of Crites' Career Maturity Inventory, MacDonald and Tseng's I-E Scale, and dichotomized ratings of typical versus atypical vocational choice were obtained from 179 freshmen to senior female student volunteers in a large New England university. Analysis of variance indicated that internally controlled women had significantly higher vocational maturity than externally controlled women (p <. 01); no differences were found in vocational maturity between those making typical or atypical vocational choices; the lowest level of vocational maturity was found for externally controlled females making atypical vocational choices. Implications of these findings for counseling are discussed.  相似文献   
920.
The proposition that impulsive children inhibit expressive behavior less than reflective children was investigated by providing third grade impulsive and reflective boys with either differential or nondifferential forms or successive discrimination training prior to tests for stimulus generalization. Consistent with specific predictions derived from Spence's theory on the roles of excitation and inhibition, it was found that: (a) Reflectives acquired the discrimination more rapidly, (b) reflectives achieved a higher level of discriminative performance, (c) impulsives exhibited more variable response reates during the nonreinforced stimulus, and (d) the type of training interacted with the child's conceptual tempo to determine the elevation and shape of the post-discrimination generalization gradients. The results provide support for the construct validity of the Matching Familiar Figures Test of reflectivity-impulsivity.  相似文献   
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