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981.
Two experiments were designed to assess whether depriving rats of food would increase the reinforcement effectiveness of wheel running (Experiment 1) and whether satiation for wheel running would decrease the reinforcement effectiveness of food (Experiment 2). In Experiment 1, a progressive-ratio schedule was used to measure the reinforcement effectiveness of wheel running when rats were deprived or not deprived of food. Completion of a fixed number of lever presses released a brake on a running wheel for 60 s, and the response requirement was systematically increased until the rat stopped pressing or until 8 hr had elapsed. The ratio value reached (and the total number of lever presses) was an inverted-U function of food deprivation (percentage body weight). In Experiment 2, when wheel running preceded test sessions, fewer food-reinforced lever presses were maintained by the progressive-ratio schedule, and responding occurred at a lower rate on a variable-interval schedule. An interpretation of these results is that deprivation or satiation with respect to one event (such as food) alters the reinforcement effectiveness of a different event (such as access to wheel running).  相似文献   
982.
Relationship between Knapp's metaphor scale of attitudes toward time and subjective estimation of fixed time intervals, measured by a modification of Lovett Doust's method, was described. Results were discussed within the framework of studies relating the measurements of cognitive styles and altered consciousness states to the dilated or accelerated perceptions of time.  相似文献   
983.
Syntactic decoding reaction times of 20 learning disabled children comprising two groups of subjects (mean age of 8 and 13 yr., respectively) were compared to the responses of normal controls matched for age and sex. An analysis of variance procedure showed that the learning disabled children and their normal peers did not differ significantly in responses to the experimental stimuli. This held true regardless of linguistic complexity, suggesting that delays in processing elementary syntactic constructions are not a concomitant of learning disabilities.  相似文献   
984.
In previous studies subjects who have learned a positioning response with kinesthetic feedback tended to make greater errors when visual feedback was provided during later trials. These subjects have always performed with both kinesthetic and visual feedback available. This study determined whether subjects with only visual feedback would produce errors similar to those who received kinesthetic plus visual feedback. Blindfolded subjects learned to move a handle to a criterion location with knowledge of results following each trial. Subjects then were assigned to one of three experimental groups, with only kinesthetic feedback, with kinesthetic plus visual feedback, or with only visual feedback. Subjects had 9 trials without knowledge of results in these feedback conditions. When visual feedback was available, subjects tended to make longer response errors. This finding replicates previous studies. Also, the similarity of performances from the conditions with visual feedback indicated the dominance of visual information in the condition with kinesthetic plus visual feedback.  相似文献   
985.
The purpose of this study was to examine the influence of age, sex, etiology, and degree of hearing loss on the static and dynamic balance performance of hearing impaired children and youth (N = 132), ages 3 to 14 yr. The subjects were individually assessed on Items 2 and 7 of Subtest 2 of the Short Form of the Bruininks-Oseretsky Test of Motor Proficiency. As expected, performance on both tasks improved with chronological age. In comparing the performance of subjects by etiology, only one significant difference emerged; those with genetic deafness were superior on static balance to those whose deafness was idiopathic. However, the mean scores for the genetic group were superior for both balance tasks. The sex of the child as well as extent of hearing loss did not affect performance in either task.  相似文献   
986.
The purpose of this study was to assess difference in academic performance among myopic, hyperopic, and emmetropic children who were learning disabled. More specifically, myopic children were expected to perform better on mathematical and spatial tasks than would hyperopic ones and that hyperopic and emmetropic children would perform better on verbal measures than would myopic ones. For 439 learning disabled students visual anomalies were determined via a Generated Retinal Reflex Image Screening System. Test data were obtained from school files. Partial support for the hypothesis was obtained. Myopic learning disabled children outperformed hyperopic and emmetropic children on the Key Math test. Myopic children scored better than hyperopic children on the WRAT Reading subtest and on the Durrell Analysis of Reading Difficulty Oral Reading Comprehension, Oral Rate, Flashword, and Spelling subtests, and on the Key Math Measurement and Total Scores. Severity of refractive error significantly affected the Wechsler Intelligence Scale for Children--Revised Full Scale, Performance Scale, Verbal Scale, and Digit Span scores but did not affect any academic test scores. Several other findings were also reported. Those with nonametropic problems scored higher than those without problems on the Key Math Time subtest. Implications supportive of the theories of Benbow and Benbow and Geschwind and Behan were stated.  相似文献   
987.
86 stutterers' disfluency patterns were examined in relation to their laterality preferences. Results suggest that young stutterers are a heterogeneous group and that specific disfluency variables were not related to ear preferences on a dichotic consonant-vowel listening task.  相似文献   
988.
The texton theory of preattentive texture perception was recently adopted over a prior model based on the global computation of dipole statistics. It is shown here that the dipole model remains a necessary adjunct unless the texton theory is modified to distinguish real from virtual features of texture perception.  相似文献   
989.
This study examined supervisor perceptions and subordinate reactions to formal performance-appraisal reviews. The performance-appraisal behaviors of supervisors and the reactions of their subordinates were studied in a sample of university employees. A factor analysis revealed that there were three dimensions of formal performance appraisals: two developmental dimensions (being supportive; emphasizing performance improvement) and one administrative dimension (discussing pay and advancement). Regression analyses suggested that supervisors supported highly rated individuals and stressed improvement efforts for poor performers. After controlling for the level of previous performance ratings, results indicated that support in the appraisal review was associated with higher levels of employee motivation, while discussing pay and advancement was associated with higher levels of employee satisfaction. Unfortunately, improvement efforts by the supervisors did not influence job performance one year later.  相似文献   
990.
According to our investigations the incidence of cataphasia, which is a subtype of schizophrenia, has become more common in the last years and on average, has started earlier in life. As the central disorder of this illness concerns thinking perhaps there exists a relation of our finding to the rapid modern development of techniques, insofar as the cognitive function is overstrained in childhood and adolescence, when the nervous system has not matured yet. Introverted individuals seem to be at a particular risk. However, it must not be disregarded that cataphasia is an inherited illness which cannot be caused by external influences, but can only be promoted in its manifestation.  相似文献   
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