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991.
Tapping rate and variability were measured as 73 normal, right-handed children in Grades 1–4 engaged in speeded unimanual finger tapping with and without concurrent recitation. Speaking reduced the rate of tapping and increased its variability to a greater extent in younger children than in older children. Developmental changes in variability but not rate were attributable to a greater number of lengthy (>500 ms) pauses in the tapping of younger children. Speaking slowed the right hand more than the left, and the degree of this asymmetry was constant across grade levels. The right-hand effect for tapping rate was not attributable to lengthy pauses. In contrast, asymmetric increases in tapping variability occurred only among children in Grade 1 and only when lengthy pauses were included in the data. The results implicate three mechanisms of intertask interference: one involving capacity limitations, a second involving cross-talk between motor control mechanisms for speech and finger movement, respectively, and a third factor involving occasional diversion of attention from tapping to speaking. These mechanisms are discussed in relation to developmental changes in mental capacity.  相似文献   
992.
Subjects in Santa Barbara, California, and Groningen, The Netherlands, participated in a seven-person social dilemma game, presented in terms of a conservation of resources problem. Prior to their decision making in the social dilemma game, subject's social motive (altruistic, cooperative, individualistic, competitive) was assessed by means of two different classification procedures. On the basis of previous research findings American subjects were expected to display relatively more competitive social motives, and Dutch subjects relatively more cooperative ones. However, no indications of crosscultural differences were found neither with regard to the distribution of social motives nor with regard to the amount of resources taken for self in the social dilemma game. In both locations, competitive subjects took most resources for self, individualistic subjects took next most, cooperative subjects took less than individualists, and altruistic subjects took the least. In addition to predictive validity, indices of the convergent validity of two social motive assessment procedures were described.  相似文献   
993.
An experiment is reported in which the effects of taxonomic organization on 7-year-old and 11-year-old children's free and cued recall of two- and four-category lists were examined. The data were analyzed using a stages-of-learning model that simultaneously delivers estimates of the impact of these manipulations on storage and retrieval components of recall. The results indicated that for the Grade 2 children providing a category label at the time of recall primarily enhanced storage whereas increasing the number of categories primarily enhanced retrieval. For Grade 6 children, on the other hand, the use of category labels to cue recall primarily enhanced retrieval, whereas increasing the number of categories affected both storage and retrieval in free recall, but only retrieval in cued recall. In addition, while older children were superior to younger children at both storing and retrieving information, age differences at retrieval were generally larger than those at storage.  相似文献   
994.
Two experiments assessed the importance of sound duration for eliciting head orientation responses from newborn infants. In Experiment 1, thirty infants turned with equal frequency toward 20-s continuous rattle sounds and 20-s trains of rattle segments. The duration of the rattle segments--14 and 100 ms (2/s), or 500 ms (1/s)--did not influence the likelihood of turning. Response latencies and durations proved quite similar for all stimuli. In Experiment 2, twenty-four infants heard continuous rattle sounds of four different durations: 1, 5, 10, and 20 s. They turned reliably to all stimulus durations; furthermore, the magnitude and temporal characteristics of head orientation responses did not differ for the four stimulus durations. These results suggest that the newborn's head orientation response may reflect a motor program that is initiated by auditory input and then executed in a similar fashion regardless of further stimulation.  相似文献   
995.
A certain family of three-state Markov processes has been widely used in experiments on children's memory. Although the statistical machinery for these models is well developed in most respects, two shortcomings have been noted in recent literature reviews. First, the parameters of the models are not identifiable. Second, goodness-of-fit tests are laborious to execute and their sampling distributions are unknown. New procedures for dealing with these difficulties are reported.  相似文献   
996.
Four experiments examined the control of observing responses by information feedback during visual discrimination learning. Second-grade children participated in Experiment 1; kindergarten, second-, and fifth-grade children were subjects in Experiments 2 and 3, and grade 5 and adult subjects were tested in Experiment 4. In order to view the stimuli, subjects in Experiments 1, 2, and 3 activated lights in viewing boxes; in Experiment 4, stimulus fixations were measured using a corneal reflection technique. Fifth graders and adults observed the discriminative stimuli for longer times on trials following negative feedback than on trials following positive feedback; in contrast, kindergartener's observing was not affected by type of feedback. Second graders showed smaller and less reliable reactions to type of feedback than did older subjects. These results support the view that visual observing is controlled by cognitive processes associated with hypothesis testing.  相似文献   
997.
The Depressive Experiences Questionnaire: revision and validation   总被引:3,自引:0,他引:3  
The present study presents a new, unit-weight scoring system for the Depressive Experiences Questionnaire (DEQ). One hundred thirty-one college students completed the DEQ, the Bem Sex-Role Inventory (BSRI), and the Beck Depression Inventory (BDI). The revised DEQ scales were shown to have substantial levels of internal consistency. The three subscales of the revised DEQ were significantly correlated with the BSRI masculinity and femininity scales but not with gender. Significant correlations were also obtained between DEQ anaclitic, DEQ introjective scales and the BDI.  相似文献   
998.
The influence of perceived somatotype on stereotypes of behavior associated with body build was investigated among 160 male and 140 female Nigerian children in secondary school. In both groups, the perception of subjects' own physiques and discrepancy between their perceived and preferred physiques significantly explained the variance in the character trait scores attributed to body types. In general, the subjects attributed positive character traits to their perceived somatotypes and undesirable traits to the physiques with which they were dissatisfied. Thus, the perception of somatotype and discrepancy between perceived and preferred physique could significantly differentiate the character traits attributed to body build among male and female children.  相似文献   
999.
In this study of the way 32 men and women between the ages of 60 to 90 coped with stressful situations, two instruments were used: the Life Experiences Survey and the Ways of Coping Checklist. Overall, health-related concerns were more frequently reported by older adults than any other stressful event. When coping responses were categorized according to four modes--intrapsychic, inaction, direct action, and information seeking--the Appalachian group was found to use the information-seeking mode; the Cherokee group, the intrapsychic mode. Significant differences were found between males and females in coping modes and life-stress categories. When groups were combined, significant correlations were noted between life stress, particularly health-related stress, and the coping modes of intrapsychic and information seeking.  相似文献   
1000.
Thirty-eight chronically mentally disabled patients who were invited to join a newly established, vocationally oriented, day treatment program in Raleigh, North Carolina, served as subjects. We attempted to determine whether demographic and psychosocial characteristics significantly differed among groups of clients who dropped out of, remained in, or refused membership in this community-support program. A variety of demographic, expectancy, psychological, and psychosocial measures were administered to each subject. Most significant was the finding that the subjects' perceived level of help and support from friends was a significant determinant of the level of program participation. Those subjects who refused to participate (refusers) perceived themselves as receiving proportionately less support than did members of the other two groups (dropouts and remainers).  相似文献   
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