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991.
Planning: Theoretical considerations and empirical evidence   总被引:1,自引:0,他引:1  
Summary A study of processes rather than of abilities characterizes much of Luria's work on cognitive functions. The three major functional organizations in terms of cognitive functions are: arousal, coding, and planning. Each of these has been described with a special emphasis on planning. Tasks appropriate for demonstrating the processes of planning are discussed and the emergence of a planning factor through factor analytic work has been described. Considerations relating to the independence of planning and coding processes in the context of normal and abnormal development are presented next. Finally, planful behavior as an integral part of purposive behavior in humans is considered in the context of consciousness.  相似文献   
992.
993.
This experiment investigated Allport's (1977) claim that normal subjects can be induced to make semantic errors of the type characterised by “deep dyslexia”. The procedure followed that used by Allport except that a subject based control for the chance level of semantic errors was included. The results replicated the original finding by producing a semantic error rate of 12·7%. It was shown, however, that this rate was not significantly higher than the calculated chance rate of 11·5%. It was concluded, therefore, that the semantic error rates reported by Allport can be accounted for in terms of a guessing artefact and thus they bear no relevance to the problem of deep dyslexia.  相似文献   
994.
A model of childhood hyperkinesis, using the Telomian-beagle hybrid dog, is described, demonstrating the interactions of genetics and separation in the development of this syndrome and in the favorable responses of some of these dogs to amphetamine. This work represents the collaboration of three laboratories, utilizing chiefly methods of inhibitory training. Inducing separation distress enhanced the resistance to inhibitory training and the favorable responses to amphetamine.  相似文献   
995.
Hand differences in the rate and variability of rapid tapping were evaluated for the intertap interval and its constituents-the key depression and key release phases of each tap. To accentuate potential hand differences, only subjects with a clear manual superiority in one hand were included. Relative manual proficiency on Fitts' reciprocal tapping task was used to exclude individuals with less-defined hand superiority or dominance, and to categorize subjects as having a dominant left (n=13) or right (n=11) hand. Analysis of variance indicated the dominant hand to have a shorter average intertap interval and thus a faster tapping rate. This hand difference in rate was found to be significant for the key-depression phase, but not the key-release.phase, of the tap. In each handedness group the dominant hand exhibited less variability in the intertap interval and both constituents. Potential associations of these findings with hemispheric asymmetries in sequential ability are discussed.  相似文献   
996.
A practicing physician reviews the contribution of Jewish ethics, as it relates to the structure of Jewish law, to the issue of abortion. The topics approached include the status of the fetus, the relationship of fetus to mother, abortion and murder, therapeutic abortion, and the rights of the mother. The discussion describes rabbinic answers to abortion requests and is followed by a summary of the Jewish attitudes toward termination of fetal life. An appendix is provided, dealing with central aspects of Jewish ethics, the structure of Jewish law, their relationship, and a note on abortion legislation in Israel.  相似文献   
997.
The development of sexual identity was studied in 686 individuals, using a fantasy measure of sexual identity that does not depend on learned sex-role stereotypes. The results showed a marked differentiation between the sexes at pre-adolescence, a loss of differentiation during the freshman year of college that most closely resembled the lack of differentiation in sexual identity of preschool children, and a reemergence of a clear sexual identity during the last years of college. Possible biological, social context, and psychodynamic-maturational explanations for this pattern of development are discussed.  相似文献   
998.
The outcomes of 68 marriages of four-year duration were compared on the basis of whether the partners had or had not cohabited premaritally. Background characteristics and personality data were assessed on those couples when there were newly married, and they were followed-up four years later to determine their current marital status, level of satisfaction, difficulty with various problem areas and the number of children born to them. No reliable differences on marital satisfaction or divorce rates between premarital cohabitors and noncohabitors were found. Cohabitors who divorced did so while reporting less marital distress than noncohabitors who divorced. Premarital cohabitors had significantly fewer children than noncohabitors. Degree of difficulty experienced on various problem areas differed between the groups. Certain personality and background variables predicted marital success differently for the two groups. Using the same selected set of six predictor variables, multiple regression equations were generated for cohabitors and noncohabitors. The cohabitors equation (R2 = .56) predicted marital success significantly more effectively than the noncohabitors equation (R2 = .28), When comparing the tri-weight vectors for these two equations, none of the predictor variables had the same influence in both groups. Theoretical implications of the findings were discussed.  相似文献   
999.
Alternative fixed-ratio fixed-interval schedules of reinforcement   总被引:2,自引:2,他引:0       下载免费PDF全文
Five rats were trained under alternative fixed-ratio fixed-interval schedules, in which food reinforcement was provided for the completion of either a fixed-ratio or a fixed-interval requirement, whichever was met first. Overall response rate and running rate (the rate of responding after the postreinforcement pause) decreased for all subjects as the fixed-ratio value increased. As the proportion of reinforcements obtained from the fixed-ratio component increased and the alternative schedule approached a simple fixed ratio, overall response rate and running rate both increased; conversely, as the proportion of reinforcements obtained from the fixed-interval component increased and the alternative schedule approached a simple fixed interval, response rates decreased. Postreinforcement pause length increased linearly as the average time between reinforcements increased, regardless of the schedule parameters. A break-run pattern of responding was predominant at low- and medium-valued fixed ratios. All subjects displayed at least occasional positively accelerated responding within interreinforcement intervals at higher fixed-ratio values.  相似文献   
1000.
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