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981.
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
982.
Examination of perceptions of human facial attributes revealed that individual attributes are similarly perceived by males and females. However, patterns of attribute interrelationships differ as a function of gender of the face. Undergraduate students (N = 280) rated pictures of 40 male or female Caucasians on 12 physical attributes (e.g., nose size, face width) and overall attractiveness. The four sets of attribute ratings (defined by rater gender and picture gender) were submitted to principal components analyses, and five-factor solutions were found for each condition (accounting for about 76% of the variance). Comparisons of the four component solutions using confirmatory factor procedures revealed that male and female raters share one factor structure when rating photographs of female faces and another factor structure when rating photographs of male faces. Multiple regression analyses revealed that the patterns of attribute interrelationships were not "perceptual units" in the perception of attractiveness, and that different "rules" are used to assess the attractiveness of male and female stimuli faces. The importance of these results for models of facial attractiveness and interfacial similarity judgements are discussed. 相似文献
983.
The early versus late selection issue in attention models was examined by means of a new methodology. Through cues or precues, attention was directed to one location of a multistimulus visual display and, while attention was so engaged, the identity of a stimulus located at a different position in the display was changed. By varying the time after display onset before the stimulus was changed, we controlled the preview time that the original stimulus was represented on the retina. Then, using a marker cue, we directed the subject's attention to the location of the changed stimulus. The subject's response was a timed discrimination between two possible target letters. The data of main interest was the effect of preview time upon the subject's latency in identifying the new target that appeared in the changed location. We found that the preview time of the original stimulus, before RT was affected to the new target, depended upon whether the original stimulus was a neutral (noise) letter or whether it was the alternative target. When the original stimulus was a noise letter, RTs to the new target were just as fast as those obtained in the control condition in which the target was present throughout the preview interval and did not change its identity. Significant effects upon RT were obtained at preview times of 83 msec when the original stimulus was one of the targets that changed to the alternative target. Preview times also varied as a function of precuing. Preview times were correspondingly shortened when the first cue occurred 50 msec before display onset, thus providing an extra 50 msec for attention to be directed to the first display location. The results were interpreted in terms of two separate information-processing systems in the human: an automatic system and an attentional system. Even though a stimulus may have been automatically processed, when the attention system is directed to that stimulus, processing starts at the beginning again. 相似文献
984.
Information-processing differences and laterality of students from different colleges and disciplines 总被引:1,自引:0,他引:1
1023 college students were assessed for hemispheric brain dominance using the paper-and-pencil test, the Human Information Processing Survey. Analysis of scores of students majoring in Advertising, Interior Design, Music, Journalism, Art, Oral Communication, and Architecture suggested a preference for right-brain hemispheric processing, while scores of students majoring in Accounting, Management, Finance, Computer Science, Mathematics, Nursing, Funeral Service, Criminal Justice, and Elementary Education suggested a preference for left-hemispheric strategies for processing information. The differential effects of hemispheric processing in an educational system emphasizing the left-hemispheric activities of structured logic and sequential processing suggests repression of the intellectual development of those students who may be genetically favorable to right-hemispheric processing. 相似文献
985.
S W Gray 《Perceptual and motor skills》1990,70(2):379-385
This investigation was designed to assess the effect of visuomotor behavior rehearsal (VMBR) with videotaped modeling on racquetball performance of beginning players. 24 male students in beginning racquetball class were randomly assigned to either VMBR with videotape modeling or relaxation and imagery (no modeling) condition for a 2-wk. training period. All subjects were pre- and posttested on forehand and backhand racquetball skill tests. Analysis indicated an effect for forehand shooting, with those given visuomotor behavior rehearsal with videotaped model exhibiting better performance than the relaxation and imagery group, but no effect for backhand shooting. 相似文献
986.
Traditional Dental Aptitude Test and academic grade point average have been shown to be poor predictors of clinical performance by dental students. To refine predictors of psychomotor skills, a wire-bending test was given to 105 freshmen at the beginning of their dental education. Grades from seven restorative preclinical courses in their freshman and sophomore years were compared to scores on wire bending and the three traditional predictors: GPA, academic aptitude, and perceptual aptitude scores. Wire-bending scores correlated significantly with six out of seven preclinical restorative courses. The predictive power for preclinical performance was doubled when wire bending was added to traditional predictors in stepwise multiple regression analysis. Wire-bending scores identified students of low performance. These preliminary results suggest that the wire-bending test shows some potential as a screening test for identifying students who may hae psychomotor difficulties, early in their dental education. 相似文献
987.
Reaction time (RT) for two three-segment target-striking responses involving changes in direction of movement was studied as a function of differences in their additive index . . . index of difficulty (A-ID). In one condition the A-ID was 9.96 and in the other, 6.76. For 16 right-handed university students, mean RT was significantly faster for the condition in which the index was 6.76. Movement times were consistent with Fitts' Law. The data support Sidaway, Christina, and Shea's 1988 prediction that for target-striking movements with changes of direction, RT is a function of the cumulative series of movement constraints. 相似文献
988.
This study is a systematic replication of the effects of insulin doses on operant behavior reinforced (in an earlier study) by fixed-ratio schedules of microwave (MW) reinforcement. In this study, insulin and dextrose doses were administered (ip) prior to fixed-interval 2-min. schedules of MW reinforcement in rats tested in a cold environment. Six Sprague-Dawley rats were conditioned to regulate their thermal environment with 5-sec. exposures of MW radiation (SAR = 0.34 Watts/kg/(mW/cm2) under the FI-2' schedules. Humulin-regular insulin and 50% solutions of dextrose were administered (ip) alternately with saline control sessions for 8-hr. durations. A within-subjects, repeated-measures 4 x 8 x 3 factorial analysis of variance design showed that insulin doses suppressed operant responding for heat, which confirmed the results of the earlier study under a different schedule. In addition, high doses of dextrose had similar suppressing effects on operant responding for heat. The data are interpreted in terms of the discriminative properties of increased thermogenesis produced by the insulin and dextrose doses. The suppressing effects were more pronounced for the first two hours, yet they persisted for approximately six hours of the 8-hr. sessions. 相似文献
989.
AN EXAMINATION OF THE EFFECTS OF USING BEHAVIOR CHECKLISTS ON THE CONSTRUCT VALIDITY OF ASSESSMENT CENTER DIMENSIONS 总被引:3,自引:0,他引:3
Although research has established the criterion-related validity of assessment centers for selection purposes, the construct validity of dimension ratings has not been demonstrated. A quasi-experimental design was used to investigate the influence of retranslated behavior checklists on the construct validity of dimension ratings for two assessment center exercises. Assessor use of behavior checklists increased the average convergent (i.e., same dimension across exercise) validity from .24 to .43 while decreasing the average discriminant (i.e., different dimension within exercise) validity (.47 to .41). Behavior checklist sums were moderately correlated with corresponding dimension ratings and demonstrated a comparable level of construct validity. It is suggested that using behavior checklists may improve dimension construct validity by reducing the cognitive demands placed on raters. 相似文献
990.
W Freier 《Psychiatrie, Neurologie, und medizinische Psychologie》1990,42(1):51-4; discussion 55-7