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991.
The article begins with a summary of eight well-substantiated conclusions drawn from research on perception in infants that have implications for theories of perception. The following section examines several traditional and modern theories of perception in the light of these conclusions. Finally, some "big issues" that have divided perceptual and cognitive theories are discussed, with the suggestion that research on infants can help reconcile the divided camps. Research on perception in young infants not only flourishes but also presents a challenge to all theories of perception.  相似文献   
992.
Strengthening local alcohol programs so as to emphasize primary prevention is an active concern among mental health professionals; yet interventions intended to achieve this aim have produced only modest shifts in program orientation in most communities. An analysis of data obtained from those active in local affairs in a small community, using Q-sort techniques, suggested that contrasting perspectives toward alcohol abuse as a social problem may stand as an unseen barrier to relevant change.  相似文献   
993.
This study evaluated the clinical validity of the Intellectual Screening, Development, and Achievement scales of the Personality Inventory for Children-Revised (PIC-R), as well as the newly derived PIC-R Factor IV scale, in identifying cognitive impairment in a clinic-referred sample of preschoolers. The clinical validity of these PIC-R subscales was also compared to that of the Minnesota Child Development Inventory (MCDI). The results showed that the PIC-R scales and Factor IV were reasonably successful in identifying cognitively impaired preschoolers, but much less successful in identifying cognitively normal preschoolers. Overall, the MCDI was the most successful in correctly identifying the preschoolers' cognitive status.  相似文献   
994.
Surface and structural similarity in analogical transfer   总被引:13,自引:0,他引:13  
Two experiments investigated factors that influence the retrieval and use of analogies in problem solving, Experiment 1 demonstrated substantial spontaneous analogical transfer with a delay of several days between presentation of the source and target analogues. Experiment 2 examined the influence of different types of similarity between the analogues. A mechanism for retrieval of source analogues is proposed, based on summation of activation from features shared with a target problem. The results of Experiment 2 indicated that both structural features, which play a causal role in determining possible problem solutions, and salient surface features, which do not have a causal role, influence spontaneous selection of an analogue. Structural features, however, have a greater impact than do surface features on a problem solver’s ability to use an analogue once its relevance has been pointed out.  相似文献   
995.
Twenty-nine children 9 to 12 years old who were identified as moderately to severely depressed using the Children's Depression Inventory were randomly assigned to either a self-control, behavioral problem-solving, or waiting list condition. The self-control treatment focused on teaching children self-management skills. The behavioral problem-solving therapy consisted of education, self-monitoring of pleasant events, and group problem solving directed toward improving social behavior. Subjects were assessed pre-and posttreatment and at 8-week follow-up with multiple assessment procedures and from multiple perspectives. At posttreatment, subjects in both active treatments reported significant improvement on self-report and interview measures of depression while subjects in the waiting list condition reported minimal change. Results were maintained at follow-up. The general success of the experimental treatments was discussed and recommendations for further treatment components were provided.Second authorship on this article is shared by Drs. Reynolds and Kaslow. The authors would like to thank Mr. Ed Guzwieski, Principal, and the teachers of Oregon Middle School for their cooperation with this study. The authors also would like to thank Mary Wysopal for conducting the posttreatment and follow-up interviews, and Carol Fairbanks for rating the audiotapes.  相似文献   
996.
The functional development of cardiac and adrenal medullary responses to reflex activation of the sympathetic nervous system was studied in preweanling spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) normotensive rats. Pups of the two strains received injections of insulin or saline at 2, 4, 8, 12, or 16 days of age and were sacrificed 3 h later. Insulin administration produces a significant decrease in circulating levels of glucose which in turn results in a centrally mediated increase in sympathetic outflow. The induction of ornithine decarboxylase (ODC) in heart and the depletion of epinephrine from the adrenal medulla served as tissue markers of functional sympathetic neurotransmission. WKY and SHR pups had comparable levels of ODC activity in heart under basal conditions. In contrast, levels of catecholamines in the adrenals were greater in SHR pups at 2 and 4 days of age. Following insulin administration, SHR pups exhibited a greater induction of cardiac ODC activity at 2, 4, and 8 days of age compared to age-matched WKY controls. However, there were no differences between SHR and WKY pups in the magnitude of the adrenal medullary response to insulin-induced hypoglycemia. These alterations in sympathetic-target tissue development during the first postnatal week of life may contribute in part to the higher arterial pressures maintained by SHRs throughout the lifespan.  相似文献   
997.
The influence of sexual experience on preference behavior was investigated in adult female rats. In the first experiment, preference behavior for sexually active males versus estrous females was investigated in female rats who were experienced with mounting behavior. Preference of these mount experienced females was compared to preference of females who were naive in this respect. Mount experience with estrous females induced a female-directed preference in ovariectomized female rats, irrespective of whether the females were treated with OIL or with testosterone-propionate (500 micrograms TP, injected once 48 h prior to testing). Sexually naive, OIL-treated females did not show a preference for males or females, but TP induced a preference for a male. Individual differences in mount frequency were not correlated with preference behavior. In the second experiment, the influence of experience with feminine sexual responses on preference behavior was investigated. OIL-treated and TP-treated females oriented equally toward males and females when they had been given the opportunity to copulate with males prior to the preference tests. The results strongly suggest that prior sexual experience is an important determinant of preference behavior. The female's behavior during sexual interactions was, however, not predictive of later preference.  相似文献   
998.
A long-term temporal component of working memory of rats trained on the radial maze has been shown to be susceptible to disruption by the protein synthesis inhibitor, anisomycin. It is not clear whether protein synthesis played a role in working memory because accurate performance on the radial maze required the storage of a large amount of information, or because the information was to be held in store for relatively long periods of time. This experiment tested these hypotheses by assessing the effect of anisomycin on choice accuracy in a comparatively simple spatial delayed alternation task. Results indicate that under the present training conditions, protein involvement in working memory is related more to the length of the retention interval than to the amount of information retained.  相似文献   
999.
A series of behavioral bioassays were conducted to determine the aggression-influencing properties of urine and other fluids. Subjects were prepuberal castrated male and female domestic pigs from commercial stocks. In the behavior assay, pigs were painted with a test fluid and grouped for a videotaped 90 min observation period. Experiment 1 validated use of videotape recording by showing that duration of aggressive behavior registered live was correlated with that obtained from video records (R = .98). In experiment 2, urine and plasma collected from actively aggressive pigs reduced the durations of aggressive behavior of test pigs compared with the effects of urine and plasma collected from socially stable, handled pigs. In Experiment 3, a new set of test pigs confirmed that urine from fighting pigs reduced the duration of attack by test pigs compared with urine from nonfighting, handled pigs. In addition, the suggested reproductive pheromone, 5 alpha-androst-16-en-3-one, substantially reduced the duration of attack. The effects of gender and aggressive state of urine-donor pigs on test pigs was determined in Experiment 4. Again, urine from castrated male and female aggressive pigs reduced attack by test pigs compared with the level of attack shown by test pigs coated with urine from handled castrated males and females. Urine from fighting and nonfighting intact males had similar effects on test pig aggression. In Experiment 5, urine was obtained from nonhandled, socially stable pigs in their home pens and again from the same pigs after they had been regrouped (aggressive). These urine types had no significant influence on test pigs' aggression over the entire 90-min observation. However, during the first 30 min nonhandled, nonfighting pigs' urine induced less aggression in test pigs than did urine from fighting pigs. Results indicate that urine and blood plasma from aggressive pigs reduces aggression by test pigs compared with the effects of urine from handled pigs. Handling may increase the aggression-promoting properties of urine, and aggression may inhibit this aggression-promoting property.  相似文献   
1000.
The claim (Jensen, 1975) that blacks are slower than whites in choice (but not simple) reaction time is examined. It is false. The claim (Jensen, 1985) that Muhammad Ali was shown to have a “very average” reaction time is examined. It is false. The claim (Vernon & Jensen, 1984) that an unpublished technical report showed blacks to be inferior to whites on a relatively content-free mental processing task is examined. It is false. Suggestions are made concerning relevant questions that might be addressed by students of race differences in intelligence.  相似文献   
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