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In two experiments, right-handed men and women were tested for ear differences in report of dichotically presented digits, with their heads straight ahead, turned 90 degrees to the left, and turned 90 degrees to the right. In Experiment 1, head turn was controlled simply by asking the subjects to fixate an appropriately located point; a right-ear advantage occurred under all conditions of head turn among the men, but only in the head-straight condition among the women. In Experiment 2, head turn was controlled by having the subjects direct a flashlight attached to their heads toward the fixation point. This eliminated the right-ear advantage under all head conditions for the men, but for the women the right-ear advantage was, if anything, more pronounced when their heads were turned than when straight. These results suggest that auditory asymmetry depends in part on whether space is perceived as divided into left and right sides, and in part of the balance between spatial and verbal requirements. Both factors, and the asymmetry itself, may interact with sex. 相似文献
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We carried out a randomized controlled trial to determine whether an intensive intervention after a suicide attempt could decrease by half the risk of a repeat attempt in the following two years. After initial assessment and randomization, experimental subjects attended 18 therapy appointments over one year, including one home visit, and measures to improve attendance. Control subjects received the usual care. Of 63 experimental subjects, 35% made a repeat attempt, and so did 30% of 63 control subjects. The study had a 99% power to detect the desired decrease of risk (30% to 15%). Clearly, the intervention did not achieve its objective. 相似文献
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