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761.
The mechanical events of bouncing and breaking are acoustically specified by single versus multiple damped quasi-periodic pulse patterns, with an initial noise burst in the case of breaking. Subjects show high accuracy in categorizing natural tokens of bouncing and breaking glass as well as tokens constructed by adjusting only the temporal patterns of components, leaving their spectral properties constant. Differences in average spectral frequency are, therefore, not necessary for perceiving this contrast, though differences in spectral consistency over successive pulses may be important. Initial noise corresponding to glass rupture appears unnecessary to categorize breaking and bouncing. The data indicate that higher order temporal properties of the acoustic signal provide information for the auditory perception of these events.  相似文献   
762.
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   
763.
A battery of information processing measures and psychometric tests of specific and general cognitive abilities was administered to a sample of 105 individuals which included 34 monozygotic and 13 dizygotic reared apart twin pairs or triplets. Correlations between information processing parameters and psychometric abilities as well as twin resemblances for the information processing parameters were examined. In a principal components analysis of the information processing parameters, three components were identified which accounted for 67% of the total variation; Overall Speed of Response (OSR), Speed of Information Processing (SIP), and Speed of Spatial Processing (SSP). OSR was significantly correlated with WAIS IQ, and psychometric measures of verbal reasoning, spatial ability, and perceptual speed and accuracy. SIP was significantly correlated with WAIS IQ, measures of verbal reasoning, and one of the perceptual speed and accuracy measures. SSP was significantly correlated with measures of both spatial ability and perceptual speed and accuracy. Due to the small size of the dizygotic twin sample, no strong conclusions could be drawn regarding the magnitude of their resemblance. The correlation between component scores of reared apart monozygotic twins was significant for OSR, but not for SIP or SSP.  相似文献   
764.
Although the use of merit pay, incentive pay, bonus pay, and job promotion are well-established measures in the private or corporate sector of American society, few examples of successful teacher merit pay systems exist. In 1983, the Eastern Washington University Department of Education surveyed six major private corporations to determine whether corporate merit pay programs could be applied to teachers and educational institutions. Survey findings suggest several reasons why merit pay programs for teachers will probably fail: (a) lack of monetary goals; (b) the necessity for subjective evaluation, which requires multiple measurement devices, extensive supervision, and time; (c) the absence of a many-tiered corporate structure in most educational institutions; and (d) increased supervisory direction that could stifle creativity and flexibility.  相似文献   
765.
To compare the predictive value of "cognitive map" and "working memory" theories of hippocampal function, the performance of rats with dorsal hippocampal lesions was compared to that of control rats in a series of experiments. In Experiment I, experimental rats learned a spatial alternation task with normal ease, but in Experiment II, they were significantly impaired on an elevated 8-arm radial maze. In Experiment III, the performance of the same experimental and control rats was compared on two versions of a 16-arm enclosed radial maze. In the first version, carpet inserts served as cues to mark eight unbaited arms and each of the remaining arms contained one food pellet. While both experimental and control rats successfully avoided the set of cued arms, experimental rats reentered uncued baited arms more frequently than did control rats. In the second version no intramaze cues were provided, but the spatial distribution of baited and unbaited arms remained the same as that used in the first version. In this uncued version, experimental rats both entered unbaited arms and reentered baited arms more frequently than did control rats, i.e., they were impaired in both "reference" and "working" memory. These findings are compatible with the hypothesis that hippocampal lesions result in an impaired capacity to form cognitive maps but they are not compatible with the working memory hypothesis. Furthermore, twelve separate evaluators classed experimental rats as using fewer mapping and more orientation strategies than control rats in the 8-arm maze.  相似文献   
766.
Two experiments are described in which subjects rated as high or low in achievement motivation were exposed to uncontrollable outcomes on a cognitive task. Effects on subsequent performance on a different cognitive task were shown to depend on level of achievement motivation, on whether the uncontrollable outcomes were predictable or unpredictable, and on whether the uncontrollable outcomes were positive or negative. These findings have important theoretical implications which are discussed.  相似文献   
767.
Two experiments are reported that examine the nature of the processing of frequency information in Spanish-English bilinguals. In the first study, subjects studied a list of English-only, Spanish-only, and mixed-language words varying in their frequency of occurrence, and under conditions of being either informed or uninformed about the later frequency test. Subjects were then shown pictures represeting the nominally presented items and had to give frequency judgments for the words depicting the objects. Frequency judgments were significantly faster when the words had been presented in a single language, suggesting a summation of access times for the mixed-language words. Instructional conditions had no effect on frequency judgments, but the latency to judge was significantly reduced for the informed subjects. In the second study, using similar acquisition procedures, subjects were shown test words in either the same or the different language from the one in which the words were originally experienced. Subjects demonstrated a clear ability to assign frequencies according to the relationship between acquisition and test language. The data were discussed in terms of supporting the hypothesis of separate bilingual language processing, and implications for the automatic nature of frequency acquisition were also addressed.This article is based on a paper originally presented at the meetings of the Southwestern Psychological Association, San Antonio, April 1983.  相似文献   
768.
Using male hooded Lister rats the effects of GABAergic and serotonergic treatments alone and with chlordiazepoxide (CDP) were compared with the behavioral effects of CDP in a conditioned conflict procedure with three components; Reward, Time Out, and Conflict. CDP (2.5, 5.0, and 10.0 mg/kg ip) dose- relatedly increased punished and time out responding, but increased rewarded responding in an inversely dose-related manner. Punished responding was enhanced by chronic treatment to a rate which remained stable between 9 and 19 injections. The GABA transaminase inhibitor ethanolamine-O-sulfate (EOS), given chronically in drinking water (5.0 mg/ml), increased punished responding linearly to a high stable level after 2-3 weeks. Rewarded and time out responding were less substantially increased. CDP given with EOS dose- relatedly increased time out and punished responding substantially above the rates found with either treatment alone. The GABA antagonist picrotoxin blocked the increase in punished and time out responding found with EOS and CDP alone. The tryptophan hydroxylase inhibitor p-chlorophenylalanine (PCPA; 100 mg/kg x 3) linearly increased punished responding for the first week of treatment. CDP with PCPA selectively and significantly increased punished responding above the rates for either treatment alone, but the increases were not as substantial as those with EOS + CDP. The serotonin reuptake inhibitor Wy 25093 reduced increases in time out and punished responding under CDP, and the precursor 5-hydroxytryptophan (5-HTP) counteracted increases in punished responding under PCPA but also substantially reduced rewarded responding. These results provide evidence that both increased GABA and decreased serotonin transmission are involved in the anticonflict effects of CDP, as EOS and PCPA both mimicked and potentiated effects of CDP, while picrotoxin, Wy 25093, and 5-HTP counteracted them.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
769.
Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems.  相似文献   
770.
Age-related changes in grooming activity in female Fischer-344 rats were observed in a home cage and in a novel testing chamber for 50 min. Compared to the home cage condition with brief handling treatment, excessive grooming was found in the novel situation. The amount of novelty-induced grooming of aged rats (26-28 months) was about two times that of young animals (6-8 months). This increase in novelty-induced grooming of aged animals was attributable to an increase in the number of grooming bouts, prolongation of each grooming bout, and a slight increase in the duration of licking elements. However, there were no age differences in the percentage of face washing and the duration of face-washing elements. These results are discussed in terms of behavioral aging and age-related changes in peptidergic pathways in the brain.  相似文献   
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