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941.
942.
In two experiments, a speeded sorting task was administered to children. In each sorting, the child was instructed to sort a deck of cards according to values on one dimension while the values of a second irrelevant dimension were held constant, were correlated, or were varied orthogonally. Experiment 1 evaluated developmental changes in perceived structure as compared with such changes in the control of attention. Different groups of kindergarten, 2d-, and 5th-grade children performed the task with spatially integrated vs spatially separated dimensions. The results indicate that with spatially integrated dimensions there is a trend from holistic to featural perception and an increase in attentional control with increasing age. Spatially separate dimensions are perceived dimensionally at all ages, but show a trend in attentional development. In Experiment 2, the spatially integrated dimensions of Experiment 1 were made separable by portraying different targets within a configuration in different colors. The theoretical implications of the results are discussed.  相似文献   
943.
The purpose of this paper is to present a new electromagnetic device which uses alternating magnetic fields for tracking movements of multiple points inside and outside the vocal tract. It is biologically safe, noninvasive, it does not interfere with speech movements, allows for multiple recording in the same subject, and for easy collection of large amounts of data. It is especially suitable for evaluation of patients with speech motor impairments.  相似文献   
944.
This study examined the relationships between metamemory and strategic behavior in impulsive and reflective children. One hundred thirty children from the fourth, fifth, and sixth grades participated. Seventy-seven of these children had been tested 3 years earlier on metamemory and cognitive tempo tasks. At pretraining, children were assessed on metamemory, cognitive tempo, summarization skills, and teacher ratings of impulsive behavior in the classroom. Next, children in three experimental groups received prose summarization instructions, summarization instructions in conjunction with metacognitive training about the importance of a reflective approach to learning, or no instructions. Following training, children were again measured on tempo, summarization skills, and teacher ratings of impulsivity. Analyses of strategy maintenance data indicated superior performance for children who had received both summarization and metacognitive training. Causal modeling analyses showed that early metamemory was an antecedent of later strategy acquisition. The dual role of metacognition as a precursor of later strategy acquisition and controller of lower level strategies was highlighted.  相似文献   
945.
946.
947.
Male rats were given bilateral lesions in either the anterior or posterior ventromedial hypothalamus (VMH). The intermale aggressive behaviour of these animals within their own territory was observed before and after the surgical procedure and compared with the behaviour of sham-operated animals. The effects of anterior VMH lesions include an increased tendency to respond with frontal threatening upon approach of a conspecific male. This behaviour closely resembles the aggressive responses described in “shock-induced aggression” tests. Posterior VMH lesions facilitate territorial aggressive behaviour characterized by approaching the opponent followed by lateral threatening and fighting. It is suggested that 2 distinct neural substrates exist, which serve to inhibit defensive (anterior-VMH) and offensive (posterior-VMH) intermale aggression, respectively.  相似文献   
948.
Forty male undergraduates were provoked following their ingestion of high or low doses of either alcohol or delta-9-tetrahydrocannabinol (THC). The expression of physical aggression was related to the quantity of alcohol ingested. The high dose of alcohol instigated more intense aggression than the low dose. The high dose of THC, on the other hand, did not increase aggressive behavior. In fact, it tended to produce a weak suppression effect.  相似文献   
949.
The paper describes the design and use of a machine, the “Psychograph,” which automatically measured the size and shape of the skull and provided evaluations of mental traits according to phrenological principles. Developed in 1930, the psychograph was billed as a diagnostic tool capable of providing suitable vocational guidance to the thousands of unemployed as a result of the Depression. Its appearance prompted a vigorous opposition from the Psychology Department at the University of Minnesota, especially in the person of Donald L. Paterson. Subsequently, the psychograph was merely exploited for its entertainment value and disappeared after the 1933 World's Fair in Chicago.  相似文献   
950.
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