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921.
The brightness of brief displays whose durations do not exceed a critical period of integration is known to covary with stimulus duration (Bloch’s law). There are cases in which the interdependence of duration and brightness introduces an unwanted confounding that must be avoided. Three methods for equating the brightness of brief stimuli displayed under computer control are described and evaluated, and an example of the outcome obtained with the most efficient procedure is reported. 相似文献
922.
Just noticeable differences in orientation are smaller at principal standard orientations than at oblique standard orientations when they are measured with the method of single stimuli. We determined whether this oblique effect is due to an anisotropy in decision factors. A first series of experiments showed that the subjects compare the stimulus with an internal criterion, and that this decision rule is used at all standard orientations. A second series of experiments determined the influence on the oblique effect of nonsensorial variables related to criterion setting. The results strongly suggest that the effect is not due to a criterial noise anisotropy and that criterion-setting processes are similar at principal and oblique standard orientations. The latter conclusion was also supported by an analysis of the sequential stimulus and response dependencies in this task. Hence, it appears that the oblique effect in line orientation discrimination, when it is measured with the method of single stimuli, is due not to decision factors but to a sensorially based anisotropy. 相似文献
923.
A. H. C. van der Heijden R. Schreuder L. Maris M. Neerincx 《Attention, perception & psychophysics》1984,36(6):577-585
This study investigates the separate activation versus coactivation issue for redundant targets in a simple letter-detection paradigm with latency as the dependent variable. The results of a one-response visual-search task are reported. Since, on single-target trials, only the target was presented and no accompanying noise element, no “distraction decrement” caused by irrelevant noise elements (Grice et al., 1984) was to be expected. The data obtained showed a clear redundantsignal effect. Subsequent detailed analysis of the latency data using Miller’s (1982) procedure indicated that the results were consistent with a separate activation model and failed to provide convincing evidence in favor of coactivation models. A further analysis of the data indicated that, in the present study, the separate channels were negatively correlated for a range of fast RTs and positively correlated for intermediate and larger RTs. No evidence in favor of Grice et al.’s (1984) distraction-decrement hypothesis was found. The conclusions of this study are that (1) a separate activation model summarizes the essential features of information processing in this simple visual search task, and (2) no convincing evidence in favor of coactivation in visual search tasks has been reported in the literature up to now. 相似文献
924.
There exist surprisingly few normative lists of word meanings even though homographs—words having single spellings but two or more distinct meanings—are useful in studying memory and language. The meaning norms that are available all have one or more weaknesses, including: (1) the collection of free associates rather than meanings as responses to the stimulus words; (2) the collection of single rather than multiple responses to the stimulus words; (3) the inclusion of only the two most frequently occurring meaning categories, rather than all meaning categories, for the stimulus words; (4) omission of the responses typical of each meaning category; (5) inadequate randomization of the presentation order of the stimulus words; and (6) unpaced presentation of the stimulus words. We have compiled meaning norms for 90 common English words of low, medium, and high concreteness using a methodology designed to correct these weaknesses. Analysis showed that words of medium concreteness have significantly more first-response meanings than do words of either low or high concreteness, lending support to the view that concreteness is a categorical, rather than a continuous, semantic attribute. 相似文献
925.
Jennifer Rusted 《Current psychology (New Brunswick, N.J.)》1984,3(3):61-71
Investigation of the role of pictures in children’s comprehension and retention of written texts has produced reports of very different levels of facilitation. This article reviews the literature with respect to a proposed explanatory model that relates the differential pictorial facilitation to the type of material used and the children’s strategy in approaching it. It is suggested that the reported enhancement of factual texts results from the utilization of pictorial adjuncts to promote encoding of a distinct and unique conceptual unit, the subsequent retrieval of which is thereby improved. With story text, the effectiveness of pictures as encoding aids is limited by the predominance of the story schema in determining encoding and retrieval. 相似文献
926.
Richard A. Griggs 《Current psychology (New Brunswick, N.J.)》1984,3(4):3-10
The present study examined the hypothesis that violation and role-playing instructions are necessary conditions for facilitation on Wason’s selection task and that facilitation due to memory cueing via thematic content is secondary. The results of a factorial experiment employing these factors did not support the hypothesis. Memory cueing was indicated as the primary factor, but violation instructions did increase the amount of facilitation observed. This interactive effect and the nature of facilitation by memory cueing are briefly discussed. 相似文献
927.
928.
929.
Experiments 1 and 2 established children’s (mean age 3 years, 7 months) subject-relative and object-relative motion thresholds at 1°31.37′/sec and 1°9.33′/sec, respectively, speeds well above those found for adults. Experiment 3 established that preschoolers, like adults, attribute object-relative motion to the smaller of two objects, with the inducing properties of the larger stimulus greatest when it is surrounding rather than adjacent to a smaller stimulus. The inducing advantage of surroundedness was equivalent for a single-element square frame and a multielement six-dot frame. 相似文献
930.
A sample of delinquent and nondelinquent male adolescents was assessed with respect to locus of control and intellectual achievement responsibility. Data were also gathered concerning age, family size, birth order, socioeconomic status, race, and school grade. Results were subjected to a multivariate analysis and showed support for a multidimensional model of locus of control. There was no difference in expectancy of control for negative academic events between delinquents and nondelinquents. In general, birth order and delinquency were the two most important determinants of locus of control. Results are discussed in terms of previous literature on locus of control with particular consideration paid to expectations of control. 相似文献