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Visual acuity for the detection of gratings at four orientations was measured for groups of ten boys and ten girls aged five to seven years, from the following four populations: Scots in Glasgow, Pakistanis in Glasgow, Gaels in Stornoway (Outer Hebrides) and East Anglians in Littleport (Cambridgeshire fenlands). The Glaswegians, both Scottish and Pakistani, showed the normal pattern of anisotropy, with poorest acuity for oblique orientations; the East Anglians showed no significant anisotropy; while the Gaels were unusual in showing poorest horizontal acuity. A group of fourteen Pakistani children in Stornoway differed slightly from a matched group of Gaels. The group differences bore little relation to the visual environments, and were probably due to genetic or cultural factors. The relatively poor horizontal acuity of the Gaels was not correlated with astigmatism. Sex differences were also found, with the boys showing higher mean acuity and a higher ratio between vertical and oblique acuity. 相似文献
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M J Nissen J L Ross D B Willingham T B Mackenzie D L Schacter 《Brain and cognition》1988,8(1):117-134
We studied an individual with multiple personality disorder in whom each of several personalities claimed to have no direct awareness of the others and to be unable to consciously remember the experiences of other personalities. A broad selection of implicit and explicit memory tests was used to determine the extent to which one personality had access to knowledge acquired by another and the circumstances in which that knowledge would be expressed. The implicit assessment of memory was a necessary but not sufficient condition for demonstrating interpersonality access. The degree of compartmentalization of knowledge in this patient depended largely on whether the interpretation of presented information was likely to differ across personalities. 相似文献
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Two experiments investigated the effects of successive reinforcement contexts on choice. In the first, concurrent variable-interval schedules of primary reinforcement operated during the initial links of concurrent chains. The rate of this reinforcement arranged by the concurrent schedules was decreased across conditions: When it was higher than the terminal-link rate, preference for the higher frequency initial-link schedule increased relative to baseline. (During baseline, a standard concurrent-schedule procedure was in effect). When the initial-link reinforcement rate was lower than the terminal-link rate, preference converged toward indifference. In the second experiment, a chain schedule was available on a third key while a concurrent schedule was in effect on the side keys. When the terminal link of the chain schedule was produced, the side keys became inoperative. Availability of the chain schedule did not affect choice between the concurrent schedules. These results show that only when successive reinforcement contexts are produced by choice responding do those successive contexts affect choice in concurrent schedules. 相似文献
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The Australian study investigated condom-specific assertiveness and condom use as a means of prevention infection from sexually transmitted diseases. 211 men participated including 83 homosexual men (aged 19-62 years) and 128 heterosexual men (aged 17-49) who completed a questionnaire that comprised demographic details such as age, monogamy, and sexual activity as well as attitudinal and assertiveness measures. General assertiveness was measured by the Rathus Assertiveness Schedule (RAS) which had been widely used across a wide range of social situations. Assertiveness relating specifically to situations involving condoms was measured by the Condom Assertiveness Scale (CAS). Intention to use condoms was positively related to favorable attitudes, which were related to condom-specific assertiveness for both groups. For the heterosexual men only, general social assertiveness was negatively related to attitudes toward condoms. For both groups, the condom-specific measure of assertiveness was positively correlated with attitudes toward condoms. Condom-specific assertiveness was positively related to general social assertiveness as measured by the Rathus Assertiveness Schedule for the homosexual, but not for the heterosexual men. The negative relationship between general assertiveness and attitude to condoms among the heterosexual men implies that the risk reducing behavior of condom use did not seem to accord with the perceptions of masculinity and social assertiveness among heterosexual men. Thus, female partners of such heterosexual men exhibiting negative attitudes toward condom use combined with assertiveness would have to overcome resistance to insist on the use of condoms. Recently some advertising campaigns have been directed at women. The promotion of condom use among heterosexual men has to deal with the perceptions of condom use as unmasculine behavior. 相似文献
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