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211.
The present study investigated the variables of method of stimulus presentation, type of focal instance, type of strategy, and sex, in a conjunctive concept attainment task. The results indicated that an all positive series of focal cards resulted in the most efficient performance. The all negative-specified group was significantly better than the all negative-unspecified group. There was no significant difference between a focus gambling strategy and a conservative focusing strategy. The simultaneous method of stimulus presentation was shown to be superior to a successive method of presentation. There was no finding of a sex difference in concept attaining ability for each experimental condition.  相似文献   
212.
Two samples, one gifted, the other “normal,” of 30 children each (11 to 13 years of age) were matched on age, sex, race, and father's occupation. A parent of each child completed the Children's Behavioral Classification Project instrument, and a profile of 30 scaled scores was obtained for each protocol. A discriminant analysis on the basis of the profiles classified 50 of the 60 Ss correctly into their respective sample category, either gifted or normal. Though the results of a multivariate analysis of variance showed no significant differences between the groups when the 30 profile factors were viewed as a whole, univariate analyses on the separate factors yielded significant group differences on several related factors. These were interpreted with caution. Additional factors displayed significant sex differences and one demonstrated a group-by-sex interaction effect.

Coefficients of pattern similarity (the rp ) were computed among all pairs of the 60 Ss. An unweighted average linkage cluster analysis grouped 34 of the 60 Ss into six clusters which accounted for 26 of 30 possible gifted children.

After an item analysis was performed on the original data, a 42 item subscale of the CBCP questionnaire was constructed which correctly classified 31 of 40 individuals in a cross-validation sample.  相似文献   
213.
The authors explored the extent to which 5th- and 6th-grade students’ anticipated responses to hypothetical peers with undesirable characteristics (e.g., being overweight) are influenced by information that each peer (a) desired (or did not desire) to change the characteristic, (b) exerted effort (or did not exert effort) to change the characteristic, and (c) was successful (or unsuccessful) in changing the characteristic. In general, the children anticipated responding more favorably to peers who were successful in overcoming an undesirable characteristic than those who were unsuccessful. However, across both outcome conditions, peers who wanted to change and exerted effort to change were rated more favorably than were peers who reported no effort to change an undesirable characteristic, regardless of whether or not they had expressed a desire to change that characteristic. For peers whose failure to change an undesirable characteristic was associated with no effort to change, those who expressed a desire to change were rated more favorably than those who expressed no desire to change.  相似文献   
214.
The authors tested 3 hypotheses about the relation of moral comprehension to prudential comprehension by contrasting comprehension of themes in moral stories with comprehension of themes in prudential stories among third-grade, fifth-grade, and college students (n = 168) in Study 1, and among college students, young and middle-aged adults, and older adults (n = 96) in Study 2. In both studies, all groups were statistically significantly better at moral theme comprehension than prudential theme comprehension, suggesting that moral comprehension may develop prior to prudential comprehension. In Study 2, all groups performed equally on moral theme generation whereas both adult groups were significantly better than college students on prudential theme generation. Overall, the findings of these studies provide modest evidence that moral and prudential comprehension each develop separately, and that the latter may develop more slowly.  相似文献   
215.
In this article the authors compared chimpanzees’ executive function with that of children. They developed a nonverbal dimensional change card sorting task, which indexed the development of executive function. Three pairs of mother and offspring chimpanzees and 30 typically developed 5-year-old children were presented with 2 target stimuli and a test stimulus comprising 2 dimensions (size and shape) on a display; they were required to sort the test stimulus according to 1 dimension (e.g., shape). After 5 consecutive correct trials, the participants had to sort the test stimulus according to the other dimension (e.g., size). The results showed that the chimpanzees often failed to sort the test stimuli according to the first and reversed dimensions. On the other hand, the children were correctly able to use both dimensions. These results indicate that chimpanzees may have less developed executive skills than children.  相似文献   
216.
We aim to analyze the effects of an 8-month physical activity intervention on cardiorespiratory fitness, body mass index (BMI), and vigilance performance in an adult obese population. We conducted an 8-month physical activity intervention based on dance and rhythmic activities. The weekly frequency was 2 sessions of 1 hr per day. Training sessions were divided into 3 phases: a 10-min warm-up, 40 min of dance and rhythmic activities, and 10 min to cool-down. To assess cardiorespiratory fitness, participants performed a modified version of the 6-min walk test from the Senior Fitness Test battery (Larsson & Mattsson, 2001; Rikli & Jones, 1999). Vigilance performance was measured by means of the psychomotor vigilance task (PVT). Two measurements were performed immediately before and after the intervention. The results revealed that participants improved their cardiorespiratory fitness, BMI, and vigilance performance after the intervention. All in all, findings contribute new empirical evidence to the field that investigates the benefits of physical activity intervention on cognitive processes in obese population.  相似文献   
217.
In this article, the focus is on a comparison of suicide attempts and substance abuse in the United States. It is argued that suicide attempts and substance abuse may function as psychologically equivalent but gender-specialized forms of self-injurious behaviors. Possible explanations for the gender segregation of suicide attempts and substance abuse are reviewed, and the benefits of crossover theories and treatments are presented.  相似文献   
218.
The authors investigated the relationships between need for cognition. knowledge, and verbal ability. Participants completed scales that measured their need for cognition, verbal ability, and knowledge about people and events that occurred during the Vietnam War era. Correlational analyses showed that the participants' need for cognition scores were modestly but positively correlated with verbal ability and knowledge and that verbal ability and knowledge were also positively correlated. The correlation between need for cognition and knowledge was small but significant when verbal ability was controlled. The conclusion drawn from these results is that need for cognition contributes to the acquisition of knowledge beyond the contribution of verbal ability.  相似文献   
219.
The cross-cultural validity of the Need for Cognition Scale and its relationship with cognitive performance were investigated in two studies. In the first study, the relationships between the scale and university entrance scores, course grades, study skills, and social desirability were examined. Using the short form of the Turkish version of the Need for Cognition Scale (S. Gülgöz & C. J. Sadowski, 1995) no correlation with academic performance was found but there was significant correlation with a study skills scale and a social desirability scale created for this study. When regression analysis was used to predict grade point average, the Need for Cognition Scale was a significant predictor. In the second study, participants low or high in need for cognition solved multiple-solution anagrams. The instructions preceding the task set the participants' expectations regarding task difficulty. An interaction between expectation and need for cognition indicated that participants with low need for cognition performed worse when they expected difficult problems. Results of the two studies showed that need for cognition has cross-cultural validity and that its effect on cognitive performance was mediated by other variables.  相似文献   
220.
In recent years evidence has accumulated demonstrating that dogs are, to a degree, skilful in using human forms of communication, making them stand out in the animal kingdom. Neither man's closest relative, the chimpanzee, nor dog's closest living relative, the wolf, can use human communication as flexibly as the domestic dog. This has led to the hypothesis that dogs’ skills in this domain may be a result of selection pressures during domestication, which have shaped dogs’ skills tremendously. One hypothesis, the so-called by-product hypothesis, suggests that dogs have been selected against fear and aggression and as a by-product this paved the way for the evolution of generally more flexible social cognitive skills, which surpassed those of their ancestor, the wolf. Another hypothesis, the adaptation hypothesis, has claimed that dogs may have been specifically selected for certain tasks for which using human forms of communication was necessary. As of yet, the mechanism underlying dogs’ understanding of human forms of communication is not fully understood. We argue here that understanding the mechanism involved will also shed light on possible evolutionary scenarios. We argue that the evidence to date suggests that dogs’ understanding of human forms of communication may be more specialized than was predicted by some and may be best explained as the result of a special adaptation of dogs to the specific activities humans have used them for.  相似文献   
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