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171.
The ability of two and three year old children to comprehend in, on and under was tested in five contexts. In the first context, where responses did not depend on the child manipulating the experimental objects, responses were invariably correct except for some difficulty with under in the youngest subjects. In the other four contexts, which did involve manipulation of the objects by the child, responses varied as a function of the noun phrases used to refer to the experimental objects which themselves remained the same across different contexts. The result suggest that the young child's comprehension of instructions involves an interaction between aspects of the instruction's lexis and syntax and the child's construal of context.  相似文献   
172.
Thirty-eight 3-year-old children served as subjects in an investigation of recognition memory in which schematic faces differing only in the orientation of the eyes were employed as stimuli. A pretest was administered to all children, after which the two experimental groups received training in either attention to the distinctive feature of the training stimuli (also schematic faces) by means of a matching task, or in labeling the faces according to how they looked (sleepy, happy, sad, mad) and in using the labels to perform a matching task. After the training session all children were given a posttest on recognition memory of the faces. The verbally trained group obtained significantly higher scores on the posttest than either the feature or control groups. These results indicate that although the children were able to discriminate the faces, evidenced in their ease of performance on the training tasks, they were not able to use this knowledge unless given training in attaching labels to the stimuli, which enabled them to store the information for later use. Results are discussed in light of Gibson's (1969) theory of the developmental interrelations of cognitive processes.  相似文献   
173.
The operant training of two retarded children simultaneously on a picture-naming task was investigated as an alternative to the more commonly reported one-to-one student-teacher ratio. In Experiment I, two conditions were compared in which the children received primary reinforcement on a fixed-ratio schedule for responding correctly on prompt and probe trials in a standardized picture-naming procedure. During the “Group Condition”, the experimenter alternated from one child to the other after each primary reinforcement, after each incorrect response, after each response omission, and after each 10-sec period in which a child did not “attend” (by making a trial-initiating response) when it was his or her turn to be worked with. During the “Individual Condition”, the experimenter worked with only one child, and presented trials whenever the child made attending responses. Experiment I demonstrated that the Group Condition was more efficient than the Individual Condition in terms of total correct responses and total pictures learned per unit of training time. Incidental learning was also found in that the children learned some of each others' pictures as well as their own, thus indicating a further advantage of the larger student-teacher ratio. In Experiment II, an attempt was made to equate the two conditions, except for the presence of two children in the Group Condition, by ignoring the child in the Individual Condition for brief periods equal to those that occurred in the Group Condition when the experimenter presented training trials to the other child. The results demonstrated that the greater efficiency of the Group Condition was not due to the manner in which training time was allocated to the two members of a group. It also replicated the finding that the children learned some of each others' words in the Group Condition.  相似文献   
174.
The present investigation had two purposes. The first was to investigate the generalizability of the theorized personality characteristics of men within Holland's occupational types to groups of men typed by their actual vocations instead of their vocational interests. The second purpose was to investigate the extent to which the wives of men in each of the occupational groups were similar to their husbands in terms of personality characteristics. Multiple discriminant analysis of the groups' 16PF scores resulted in significant overall groups differentiation and in two significant discriminant functions labeled tender-mindedness and self-confidence. The second finding was that Social and Enterprising men were significantly similar to their wives on personality dimensions consistent with the defining characteristics of the respective Holland groups. Implications of the present results and suggestions for future research are presented.  相似文献   
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The study was designed to explore two areas: (1) the concurrent validity of Holland's theory for employed college degreed women using two different operational definitions (Vocational Preference Inventory and the Self-Directed Search) of vocational orientation; and (2) the relationships among same named scales across the VPI and the SDS. Concurrent validity was studied by administering the VPI and the SDS to 179 women workers in occupational environments consistent with Holland's six vocational environments. In general, the findings indicate that the VPI and SDS scales tend to effectively discriminate among the occupational groups consistent with Holland's theoretical framework. In addition, the correlation coefficients for same named scales for the two inventories were all found to be significant. In sum, the results of the study lend some support to the concurrent validity of Holland's theory for employed college degreed women.  相似文献   
179.
Laboratory dogs were trained to press a response panel to postpone shocks during daily one-hour avoidance conditioning periods. Each dog was also confined in the experimental environment for 5 hours prior to the avoidance periods. Blood pressure and heart rate were monitored continuously during these experiments from chronically indwelling arterial catheters. Extended training resulted in the emergence of a cardiovascular response pattern during the pre-avoidance interval characterized by gradual increases in blood pressure together with decreases in heart rate. Elevations in both blood pressure and heart rate were sustained during the avoidance periods. During sessions in which alpha adrenergic activity was suppressed by phenoxybenzamine, absolute levels of blond pressure were found to be lower than during control (non-drug) sessions, but a progressive rise in blood pressure continued to be observed during pre-avoidance. These results suggest that sustained cardiovascular responses during avoidance periods are associated with activation of the sympathetic nervous system, but that the gradual rise in blood pressure during pre-avoidance is due to other factors.  相似文献   
180.
Methylphenidate, 0.5 mg/kg, injected intravenously, was used in 10 normal (A line) and 10 genetically nervous (E line) dogs in a blind-design experiment to aid in prediction, from cardiovascular recordings alone, of behavioral normalityversus nervousness. The prediction was 75 per cent correct, based on heart rate (HR), form of the electrocardiogram (EKG), pattern of sinus arrhythmia, and pattern of HR response to methylphenidate. Nervous dogs were found to have slower baseline HR’s, delayed return of HR to baseline after methylphenidate, greater occurrence of baseline EKG abnormalities and much greater frequency of these after methylphenidate. Degree of nervousness was found to correlate rather highly (1)negatively with baseline HR level, (2)negatively with speed of BP response, and (3)positively with frequency of some of the EKG manifestations. These data, indicative of a relative inertness of physiological functions of nervous pointer dogs compared with normal pointers, are consistent with the behavioral and some of the biochemical findings previously reported.  相似文献   
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