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41.

Two experiments investigated the role of lithium-mediated environmental conditioning on instrumental performance. Experiment 1 demonstrated that a novel taste consumed in one arm of a T maze prior to lithium-induced toxicosis reduced performance in this environment whereas similar aversions conditioned in the home cage failed to alter maze performance. Experiment 2 showed that maze performance in a straight alleyway was decremented during extinction only in a group that actually traversed the alley prior to drinking saccharin and receiving lithium injections. This demonstrated that the instrumental decrement observed in Experiment 1 was due not only to the presence of an unpalatable flavor in the goalbox during the test.

  相似文献   
42.

Galef and his colleagues have repeatedly shown that one rat may transfer information regarding the type of food it has consumed to other conspecifics. Such experiments typically have been conducted in wire-mesh cages or a wooden maze. The present experiments sought to extend this paradigm to the open-field foraging situation having six food patches to choose from. Following interaction with a demonstrator that had consumed either a cocoa or a cinnamon diet, single observers (Experiment 1) were tested in the foraging situation. Food-consumption scores indicated that observers consumed significantly more of their specific demonstrator’s diet than a second diet that was available also. Experiment 2 involved the simultaneous testing of two observers in the foraging laboratory. In Experiment 3 two observers were once again tested, but each had been provided a different food-type message prior to foraging. Positive results, mirroring those of Experiment 1, were obtained in both Experiments 2 and 3. The results of these three experiments underscore the robustness of this phenomenon and its generalizability to other testing conditions.

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43.
One of the possible adaptive costs of coping with stress is diminished capacity to respond to subsequent adaptive demands. This paper examined the complex interplay between major life events and one source of chronic strain. Residents of the greater Los Angeles metropolitan area exposed to higher levels of smog, who had also experienced a recent stressful life event, exhibited poorer mental health than those exposed to pollution who had not experienced a recent stressful life event. There were, however, no direct effects of smog levels on mental health. These patterns of results were replicated in both a cross-sectional and a longitudinal study. The interplay of psychosocial vulnerability and environmental conditions is discussed.  相似文献   
44.
45.
Previous experimental investigation of the effects of repeating an unfamiliar stimulus suggests that mere exposure breeds attraction (e.g., Zajonc, 1968). On the other hand, correlational work with naturally occurring stimuli such as names, music, or landscapes suggests that there is also an overexposure effect: the preference function does rise with familiarity at first but then reaches a turning point and diminishes. The study (N=72) demonstrates this inverted-U relationship in an experimental setting. The stimuli were synthetic nonsense speech, permitting exact control of exposure durations and interstimulus intervals. The critical factors for demonstrating the effect are probably (1) the inclusion of a large number of repetitions, and (2) blocked repetition of each stimulus in a homogeneous sequence not interspersed with other more or less frequent stimuli.  相似文献   
46.
47.
The past fifteen years, in particular, have seen a major increase in the extent to which both adolescents and young adults are engaging in sexual intercourse. While several studies call attention to the increasing incidence among college/university students, the concomitant shifts in the sociopsychological realms of sexuality are also important dimensions which impact upon sexual concerns of youth. Hence, the purposes of this study are to examine the behaviors, attitudes, and concerns of students who have engaged in coitus, as well as any changes they seek in their sex lives. The sample consisted of 123 never-married male and 205 never-married female undergraduate students from a state university. The data were obtained by utilizing an anonymous questionnaire administered to volunteers during regular university classes. Among the coitally active, 67.4% of males were psychologically satisfied after their first sexual experience, but only 28.3% of females. In contrast, 80.9% of males and 28.3% of females reported current psychological satisfaction with their sexual experiences. Significant differences between genders focused on male dissatisfaction with infrequent opportunities for sexual intercourse, lack of variety of sex partners, and insufficient oral-genital stimulation, whereas females expressed concerns relating to lack of stimulation to their breasts, painful sexual intercourse, lack of orgasm during sexual intercourse, and feelings of guilt and fear. An increasing awareness of current sexual behaviors, attitudes, and concerns of university students can help family life educators to meet student needs as they react to changes in interpersonal relationships, families, and society.  相似文献   
48.
Testicular self-examination (TSE) can lead to early diagnosis and treatment of testicular cancer, the third leading cause of death in young men. We evaluated the effectiveness of a brief and specific checklist for teaching TSE skills. Ten men were videotaped while performing testicular self-examinations before and after training. The TSE training resulted in large and significant increases in the number of TSE steps completed and duration of the TSE. Two urological validation measures supported the improvements observed in the mens' self-examinations. Subjects reported continued performance of TSE during a follow-up telephone interview. This pilot study indicates that a brief and specific checklist is an effective strategy for teaching early cancer detection skills.  相似文献   
49.
The purpose of this paper is to examine the usefulness of factor analysis in developing and evaluating personality scales that measure limited domain constructs The approach advocated follows from several assumptions that a single scale ought to measure a single construct, that factor analysis ought to be applied routinely to new personality scales, and that the factors of a scale are important if it can be demonstrated that they are differentially related to other measures A detailed study of the Self-Monitoring Scale illustrates how factor analysis can help us to understand what a scale measures A second example uses the self-esteem literature to illustrate how factor analysis can clarify the proliferation of scales within a single content domain Both examples show how factor analysis can be used to identify important conceptual distinctions Confirmatory techniques are also introduced as a means for testing specific hypotheses It is concluded that factor analysis can make an important contribution to programmatic research in personality psychology  相似文献   
50.
There are very few women who take up careers as engineers - especially at the non-professional level. The present research attempts to throw some light on this issue, examining by means of a postal questionnaire the educational experiences of 22 young women craft and technician apprentices in a variety of engineering jobs. Comparisons are made with 33 similar young women who have chosen more traditional 'female' occupations. The results show significant differences between engineers and non-engineers in terms of their subject choices and curriculum opportunities at school and their perceptions of the attitudes of parents to wards their careers. Possible implications of the findings for developments in curriculum planning and careers guidance are explored.  相似文献   
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