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901.
A mathematical model is developed to describe sequential effects in two-choice reaction time experiments with a short response-stimulus interval. Evidence is briefly discussed that in conditions with short response-stimulus intervals, automatic aftereffects dominate sequential effects, and the influence of subjective expectancy can be neglected. In these conditions the model premises three components of automatic aftereffects--facilitation, inhibition, and noise, with a common decay factor. Influence of response-stimulus interval and practice on sequential effects are examined and related to parameter changes in the proposed single-decay model. The decrease of automatic aftereffects with increasing response-stimulus interval is primarily ascribed to an increasing decay factor. The parameter representation of the model also clarifies the issue of the disappearance of automatic aftereffects with practice. It shows a gradual fading of inhibition in the initial stages of practice, together with a slower decrease of the facilitation effect. The single-decay model provides a satisfactory explanation for the processes involved in compatible two-choice reaction time with short response-stimulus interval.  相似文献   
902.
Integrating pictorial information across eye movements   总被引:5,自引:0,他引:5  
Six experiments are reported dealing with the types of information integrated across eye movements in picture perception. A line drawing of an object was presented in peripheral vision, and subjects made an eye movement to it. During the saccade, the initially presented picture was replaced by another picture that the subject was instructed to name as quickly as possible. The relation between the stimulus on the first fixation and the stimulus on the second fixation was varied. Across the six experiments, there was about 100-130 ms facilitation when the pictures were identical compared with a control condition in which only the target location was specified on the first fixation. This finding clearly implies that information about the first picture facilitated naming the second picture. Changing the size of the picture from one fixation to the next had little effect on naming time. This result is consistent with work on reading and low-level visual processes in indicating that pictorial information is not integrated in a point-by-point manner in an integrated visual buffer. Moreover, only about 50 ms of the facilitation for identical pictures could be attributed to the pictures having the same name. When the pictures represented the same concept (e.g., two different pictures of a horse), there was a 90-ms facilitation effect that could have been the result of either the visual or conceptual similarity of the pictures. However, when the pictures had different names, only visual similarity produced facilitation. Moreover, when the pictures had different names, there appeared to be inhibition from the competing names. The results of all six experiments are consistent with a model in which the activation of both the visual features and the name of the picture seen on the first fixation survive the saccade and combine with the information extracted on the second fixation to produce identification and naming of the second picture.  相似文献   
903.
What is the relation between the ability to control visceral responding on a biofeedback task and the ability to report behaviors actually contributing to this performance? Subjects received biofeedback training for unidentified visceral responses and then gave written reports about what they had done to control the feedback displays. Independent judges were given these reports and, on the basis of knowledge about activities known to contribute to visceral activity, were asked to determine the visceral responses for which the subjects had been trained. The reports of subjects who succeeded at bidirectional control of heart rate (Experiment 1) or sudomotor laterality (Experiment 2) showed awareness of behaviors related to feedback as assessed by this procedure, whereas the reports of subjects who failed at bidirectional control did not. Subsequent experiments indicated that these results did not depend on a learning strategy that might have been specific to the initial studies. These findings call into question the view that people are unaware of what they have done to produce the response after training on biofeedback tasks. Earlier studies reporting lack of awareness in biofeedback are discussed in light of factors that affect the measurement of biofeedback learning and response awareness.  相似文献   
904.
Individual differences in loudness processing and loudness scales   总被引:1,自引:0,他引:1  
Parameters of the psychophysical function for loudness (a 1000-Hz tone) were assessed for individual subjects in three experiments: (a) binaural loudness summation, (b) temporal loudness summation, and (c) judgments of loudness intervals. The loudness scales that underlay the additive binaural summation closely approximated S. S. Stevens's (1956) sone scale but were nonlinearly related to the scales that underlay the subtractive interval judgments, the latter approximating Garner's (1954) lambda scale. Interindividual differences in temporal summation were unrelated to differences in scaling performance or in binaural summation. Although the exponents of magnitude-estimation functions and the exponents underlying interval judgments varied considerably from subject to subject, exponents computed on the basis of underlying binaural summation varied less. The results suggest that interindividual variation in the exponent of magnitude-estimation functions largely reflects differences in the ways that subjects use numbers to describe loudnesses and that the sensory representations of loudness are fairly uniform, though probably not wholly uniform, among people with normal hearing. The magnitude of individual variation in at least one measure of auditory intensity processing, namely, temporal summation, seems at least as great as the magnitude of the variation in the underlying loudness scale.  相似文献   
905.
Learned helplessness theory predicts that animals exposed to inescapable shock acquire an expectancy of response-reinforcer independence, which proactively interferes with learning of response-reinforcer dependence. The theory also predicts that this expectancy can increase sensitivity to subsequent instances of response-reinforcer independence. These experiments test the latter prediction in a paradigm that minimizes the confounding effects of shock-induced activity deficits. Rats were trained to respond for food, then given either escapable, inescapable, or no shock. Subsequently, they received two sessions of response-contingent food followed by sessions of noncontingent food deliveries. During this phase, inescapably shocked animals decreased responding faster than did controls. Experiment 2 replicated this finding with a different schedule of food delivery and a procedure that more directly minimized the possibility that the outcome is due to either direct or indirect shock-induced activity changes. These results support the prediction that uncontrollable aversive events can increase an animal's sensitivity to noncontingent response-reinforcer relationships.  相似文献   
906.
The rationale for and method of computing a measure of stuttering recurrence that is superior to methods previously developed is presented. This measure, the recurrence ratio, contrasts especially with the traditional measure of “consistency,” the percentage measure, which yields misleading values.  相似文献   
907.
The present study explored individual differences in performance of a geometric analogies task. Whereas past studies employed true/false or two-alternative items, the present research included four-alternative items and studied eye movements and confidence judgements for each item performance as well as latency and error. Item difficulty proved to be a function of an interaction between the number of response alternatives and the number of elements in items, especially for subjects lower in fluid-analytic reasoning ability. Results were interpreted using two hypothesized performance strategies: constructive matching and response elimination. The less efficient of these, response elimination, seemed to be used more by lower ability subjects on more difficult items. While two previous theories resemble one or the other of these strategies, neither alone seems to capture the complexity of adaptive problem solving. It appears that a comprehensive theory should incorporate strategy shifting as a function of item difficulty and subject ability.Componential models, based in part on past research, revealed that a justification component was activated and deactivated depending upon the nature of the analogy being solved. In addition, two new components, spatial inference and spatial application, were identified as important on some items, suggesting that different geometric analogy items invoke different cognitive processing components. Thus, a comprehensive theory should also describe component activation and deactivation.  相似文献   
908.
A survey of published and private opinions of mental health professionals revealed a previously hidden consensus concerning certain values that enhance mental health. These values concern Freedom, Love, Identity, Truth, Universals, Symptom Management, and Work. There was disagreement about the effect of many other values on mental health. It is my contention that values permeate counseling and psychotherapy, that the values of conselors and therapists should be more explicit, and that values should be openly used to guide and evaluate treatment.  相似文献   
909.
The accuracy and response latency of absolute frequency judgments were measured as a function of test lag (the number of intervening items between presentations of a test item) in a continuous memory task. Frequency was varied from one to three presentations in Experiments 1 and 2 and from one to five presentations in Experiment 3. The proportion of correct responses decreased as frequency increased, and correct mean response time tended to increase with frequency. Both accuracy and correct mean response time were found to be largely a function of the most recent test lag. The lag-latency functions were best described by piecewise linear functions, with the breakpoint occurring between lags 1 and 2. Continuous frequency estimation was also shown to improve with extended practice. The implications of the results are discussed with reference to trace strength, numerical-inference, and multiple-trace theories of frequency discrimination.  相似文献   
910.
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