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941.
Patterson R Geri GA Dyre BP Pierce BJ Akhtar SC Covas CM Morgan W 《Perception & psychophysics》2006,68(4):593-600
In two experiments, we manipulated the properties of 3-D objects and terrain texture in order to investigate their effects on active heading control during simulated flight. Simulated crosswinds were used to introduce a rotational component into the retinal flow field that presumably provided the visual cues used for heading control An active control task was used so that the results could be generalized to real-world applications such as flight simulation. In Experiment 1, we examined the effects of three types of terrain, each of which was presented with and without 3-D objects (trees), and found that the presence of 3-D objects was more important than terrain texture for precise heading control In Experiment 2, we investigated the effects of varying the height and density of 3-D objects and found that increasing 3-D object density improved heading control, but that 3-D object height had only a small effect. On the basis of these results, we conclude that the vertical contours improved active heading control by enhancing the motion parallax information contained in the retinal flow. 相似文献
942.
Patterns of mean-level change in personality traits across the life course: a meta-analysis of longitudinal studies 总被引:9,自引:0,他引:9
The present study used meta-analytic techniques (number of samples = 92) to determine the patterns of mean-level change in personality traits across the life course. Results showed that people increase in measures of social dominance (a facet of extraversion), conscientiousness, and emotional stability, especially in young adulthood (age 20 to 40). In contrast, people increase on measures of social vitality (a 2nd facet of extraversion) and openness in adolescence but then decrease in both of these domains in old age. Agreeableness changed only in old age. Of the 6 trait categories, 4 demonstrated significant change in middle and old age. Gender and attrition had minimal effects on change, whereas longer studies and studies based on younger cohorts showed greater change. 相似文献
943.
Prior research indicates survey procedures that signal significance and individualized mailings have higher response rates. Thus, it was hypothesized that surveys delivered via Priority mail would result in higher return rates than surveys delivered via First-Class. 260 surveys were sent to individuals randomly selected from lists of licensed physical and behavioral healthcare providers in Alaska and New Mexico. Half of the selected individuals were assigned randomly to receive mailings using Priority mail, the other half received First-Class mailings. Return rate was 39% for First-Class and 35% for Priority. Z tests of proportion indicated no statistically significant differences between methods. Given increased costs with no resultant increase in response rate, sending surveys to potential participants via Priority mail does not appear warranted. 相似文献
944.
Piacentini J Himle MB Chang S Baruch DE Buzzella BA Pearlman A Woods DW 《Journal of abnormal child psychology》2006,34(5):647-656
Tic frequency was assessed and compared across home and clinic as well as three experimentally-manipulated situations in order to assess the phenomenon of tic reactivity. Forty-three youngsters with chronic tic disorder recruited from two geographically-distinct sites were videotaped over three weekly laboratory visits under each of the following conditions: (1) alone/camera present, (2) other present/camera present, and (3) alone/camera hidden. Contrary to expectation, more tics were observed during overt as compared to covert observation, while the presence of another person had no overall impact on tic expression. Mean tic counts obtained from clinic observation did not significantly differ from those obtained at home collected either one day before or after. Tic frequency counts were remarkably stable over the three weekly assessments both at home and clinic. Study findings are consistent with past observations that tic expression can be influenced by environmental factors and suggest the stability of tic frequency may exhibit greater temporal and setting stability than previously thought. The clinical and research implications of these results are discussed. 相似文献
945.
946.
In four studies, the authors investigated the extent to which expectations for personality traits in age-graded roles correspond to patterns of personality trait change across the life course. In Studies 1 (N = 43) and 2 (N = 126), the authors examined the age-graded roles of high school student, college student, parent, and grandparent and found that expectations for how people behave in these age-graded roles showed strong parallels to the documented pattern of personality trait development and that this pattern of expectations was largely shared by younger and older participants. In Studies 3 (N = 252) and 4 (N = 123), the authors separated age and role information (e.g., marital, parental, and employment status) and found that people use both sources of information independently in forming expectations of others. The implications for understanding the interplay of expectations and personality trait development are discussed. 相似文献
947.
948.
College students, especially women, demonstrated negativity toward math and science relative to arts and language on implicit measures. Group membership (being female), group identity (self = female), and gender stereotypes (math = male) were related to attitudes and identification with mathematics. Stronger implicit math = male stereotypes corresponded with more negative implicit and explicit math attitudes for women but more positive attitudes for men. Associating the self with female and math with male made it difficult for women, even women who had selected math-intensive majors, to associate math with the self. These results point to the opportunities and constraints on personal preferences that derive from membership in social groups. 相似文献
949.
950.
Individual differences in sentence memory 总被引:1,自引:0,他引:1
Results from an experiment with two parts are presented in this paper. In part one, participants listened to sentences containing two, three, four, or five clauses, and were asked questions about the content of the sentences. The results of part one demonstrate that an important unit of representation in sentence memory is the clause, and not some other component of discourse structure. In part two, the same group of participants performed eight different short-term storage/working memory tasks. A composite complex span score was computed for each participant based on three working memory tasks closely based on Daneman & Carpenter's (1980) reading span task. This working memory measure was significantly correlated with the participants' performance on the sentence memory task in part one. A second working memory measure—N-back—was also significantly correlated with the participants' performance on the sentence memory task, and there was no correlation between their performance on the complex span task and the N-back task. It is therefore concluded that (i) working memory consists of a number of dissociable components; and (ii) memory for sentences taps into more than one of these working memory components. Furthermore, the high correlations of sentence memory with the complex span and the N-back tasks (neither of which are language processing tasks) suggests that memory for sentences is not simply a result of linguistic experience; rather, it is likely that an independent working memory component contributes to participants' performance on the sentence memory task. 相似文献