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881.
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Effects of alcohol and extended practice on divided-attention performance   总被引:3,自引:0,他引:3  
The effects of alcohol and extended practice on divided attention were investigated using a visual tracking task and an auditory detection task. Subjects performed the tasks with and without alcohol, under single-task (S) and dual-task (D) conditions, both before and after they had received extended practice under single-task conditions without alcohol. Tracking accuracy improved with practice and was impaired under divided-attention conditions but was not affected by alcohol. Speed of detection was impaired by alcohol, improved by practice, and impaired by divided attention. Extended practice did not reduce the influence of alcohol. The effects of both alcohol and practice on speed of detection were significantly greater under dual-task conditions than under single-task conditions. Analysis of detection-task reaction times in terms of relative divided-attention costs, (D-S)/S, showed no effect of alcohol, but a highly significant reduction in costs with extended practice. It is concluded that (1) alcohol and practice can have quantitatively, but not qualitatively, similar effects on speeded performance, and (2) the effect of alcohol is not influenced by the attentional requirements of the task.  相似文献   
883.
Peer-group association and adolescent tobacco use   总被引:10,自引:0,他引:10  
Mosbach & Leventhal (1988) examined the relation of cigarette smoking to peer-group identification in rural Wisconsin adolescents. They found that among dirts (problem-prone youth), regulars (average youth), hot-shots (good social or academic performers), and jocks (athletes), youth most likely to smoke were dirts and hot-shots. We performed a replication with a Southern California cohort and also for use of smokeless tobacco. We hypothesized that jocks would be the main users of smokeless tobacco. We identified the same groups and an additional one, skaters (skateboarders or surfers). As Mosbach & Leventhal found, cigarettes were used most by dirts. Contrary to their results, but consistent with other research, we found that hot-shots were least likely to smoke. Contrary to our prediction, we found that skaters and dirts were more likely to use smokeless tobacco than were jocks. Our data show that both tobacco forms are used by problem-prone youth.  相似文献   
884.
A subsample of 814 sexually experienced adolescent females from the 1979 U.S. National Survey of Young Women was analyzed to assess the correlates of age at 1st sexual intercourse. Multiple regression procedures were used to examine sets of variables sequentially. In the hierarchical regression model, the control variables (respondent's age, race, religion, and age at menarche), along with 3 independent variables (household income, ideal age at 1st marriage, and ideal age for 1st birth), predicted age at 1st intercourse. The control variables accounted for a major portion of the variance in the model. Of the controls, chronological age and age at menarche were highly significant across all models tested.  相似文献   
885.
In this paper, we describe an apparatus for measuring reaction times and movement times involved in reaching for real objects. Subjects view an object through a liquid crystal window, which serves as a shutter that can be made clear or opaque quickly (10 msec from opaque to clear, 30 msec from clear to opaque). The subject’s hand rests on a microswitch-equipped home key, and the object sits on a force-sensitive platform so that initiation of reach and time of contact with the object can be marked accurately. The apparatus interfaces with an IBM PC/AT through a digital I/O parallel port, so that reaction times and movement times are recorded automatically.  相似文献   
886.
Body size estimates of 69 children aged 5–13 years were obtained using a TV video methodology. Tasks included an adjustment procedure where children manipulated the width of their body image on a TV, and a discrete task, where they judged the accuracy of their TV image which was presented as either normal or distorted, that is, too wide or too thin. On the continuous task, judgments were more accurate on ascending trials where children had to increase the width of the image. On the discrete task, a signal detection analysis revealed older children were better in detecting size distortion in their images and that the differences were due to differences in the biological sensory system and not due to a bias to report that they were too fat or too thin. However, there were response bias differences between genders. Females were more likely to report size distortion with increasing age while males were less likely.  相似文献   
887.
We examined the concurrent relationship between late adolescent attachment to parents and peers and two broad indices of adolescent adaptation—personal and social identity and adjustment to college. Participants included 130 college freshmen and 123 upperclassmen. Although freshmen were disadvantaged relative to upperclassmen with respect to social and personal-emotional adjustment, there were no group differences on the attachment measures, on the measures of academic adjustment and goal commitment, and on the measure of social identity. Freshmen scored higher on personal identity than did upperclassmen. Women reported less alienation from peers, had more trust and better communication with peers, and had higher scores on personal and social idenitity than men. The attachment variables were significant predictors of personal and social identity. Pervasive relations were also found between attachment and adjustment to college, particularly for the upperclassmen sample.  相似文献   
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890.
In spite of a history wherein queer theory has openly rejected phenomenology, phenomenology has gained increasing interest amongst queer theorists. However, Husserl’s phenomenology is often marginalized in attempts to integrate queer theory with phenomenology, and when Husserl is addressed specifically, his work is often treated superficially or even misrepresented. Given this, my first goal is to demonstrate how Husserl’s work is already open to positions considered fundamental to queer theory, and that Husserl is often explicitly arguing for these positions himself. In doing so, I wish to show that Husserl’s phenomenology is well fitted for complementary engagement with queer theory. My second goal is to work through some ways in which Husserl’s phenomenology and queer theory can work together in detail to accomplish shared theoretical goals. Although this will not be a full-blown analysis—which would exceed the parameters of this article—my hope is to provide a certain amount of in depth work that can then assist further analyses that combine these methods.  相似文献   
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