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31.
The possibility that rats can navigate in the Morris water maze by reducing the difference between the memorized platform scene and the current sensory input was tested in nine blind rats. A computerized videosystem monitored the rats' movements in the pool and converted the rat-target distance into tones the frequency of which increased in 64 equal steps from 120 Hz at 128 cm to 7680 Hz at 0 cm. During 15 days of training to find a fixed platform position from different starting points (12 trials per day) average escape latencies decreased from 39.0 to 25.4 s. The performance significantly deteriorated when the acoustic distance signalization was omitted and/or when the target position was changed form trial to trial. It is concluded that blind rats solved the task by simultaneously employing search strategy based on position responses, mapping using acoustic background beacons, and distance reduction navigation. It is argued that the various strategies are additive and that their relative significance depends of the conditions of the experiment. 相似文献
32.
Despite widespread popular belief in the activation of recurrent lesions in genital herpes simplex virus (HSV) by psychosocial stress, little empirical evidence supports that contention. This study retrospectively examined the role of stress in activation of HSV lesions as mediated by social support. Participants were 59 volunteers who had self-reported culture-positive genital HSV for at least 10 months. Measures of stress proneness (State-Trait Anxiety Inventory; STAI-Trait), recent stressful events (Schedule of Recent Events; SRE), and subjective appraisal of stress (global self-rating) were administered along with measures of general social support and herpes-specific social support. When retrospective reports of HSV symptoms were examined using a multiple-regression approach, duration of disease and amount of herpes-specific social support were found to be significant moderators of the relation between stress and number of HSV recurrences in the preceding 12 months. When duration of disease was short (less than 4 years), stress (SRE) and number of recurrences were positively associated; when disease duration was longer, there was no relationship. Similarly, at low levels of herpes-specific social support, a positive relation between stress (SRE) and number of recurrences was found. However, at higher levels of herpes-specific social support, no association was found. No relation was found between stress proneness (STAI-Trait) and HSV symptoms. However, subjective appraisal (global rating) of stress in the preceding 12 months was positively and significantly correlated with reported number of recurrences. Results are discussed in terms of their clinical implications. 相似文献
33.
Black and White college students were studied to determine reactions to moral dilemmas when the race of the central character in the dilemma was changed. 相似文献
34.
James B. Wade Ph.D. Robert P. Hart Ph.D. Donald F. Kirby M.D. Peter R. Mills M.D. 《Group》1988,12(3):172-178
This study evaluated the efficacy of the Garren-Edwards Behavior Modification Program, which uses the Garren-Edwards Gastric Bubble as an adjunct to treatment. Group therapy sessions were conducted with 23 morbidly obese subjects for 6 months on a biweekly basis. Each therapy session used a five-stage problem-solving sequence designed to facilitate adaptive behavioral alternatives. In evaluating weight change, a multivariate analysis of variance was conducted along with two preplanned orthogonal comparisons. Patients lost significant amounts of weight between initial to 3-month (p<.0001) and 3- to 6-month intervals (p<0001). A similar treatment effect was noted in an additional sample of 24 morbidly obese subjects following 3 months of treatment (p<0005). The findings support the value of longer goal-oriented programs in promoting continued weight loss. Implications for treatment process and therapist interventions prompted by this new format are discussed. 相似文献
35.
This article explores how the sales budget is set in a business organization. Findings from a longitudinal participant observation study revealed that the sales budget is considered of great importance to the organization as sales estimates serve as premises for planning of production and supply and new product developments. It was observed that the sales budget was based on a narrow, inner-directed perspective, almost looking away from important environmental driving forces such as competitors and customers. The findings also showed that individuals involved in the sales budgeting process behaved opportunistically, influencing the budgetary process and outcomes. Theoretical and normative implications are highlighted. 相似文献
36.
37.
The belief is widely held that humor is related to recovery from, and perhaps an increased resistance to, coronary and other
stress-related diseases. Such generalizations do not typically distinguish between benign and hostile humor. In the present
research, the relationship between a measure of proneness to coronary heart disease (CHD) and appreciation of hostile and
nonhostile humor is examined. In two studies, one with college students and one with patients suffering from CHD, the relationship
between humor preferences and the coronary-prone (Type A) behavior pattern was examined. Each subject was given the Jenkins
Activity Survey as a measure of the coronary-prone personality type, and aggressive and nonaggressive jokes to rate for funniness.
Hostile humor was preferred to nonhostile humor by all groups, but among those suffering from CHD, those who could be classified
as “Type B’s” preferred nonhostile humor. The results indicate that those less prone to CHD appreciate both hostile and nonhostile
humor, while Type A’s seem to enjoy hostile humor only. 相似文献
38.
Fear of Success (FOS) was originally conceived as a unidimensional motive. However, there is both theoretical and empirical
support for the hypothesis that FOS is multidimensional. We factor analyzed the responses of 236 undergraduates to twenty-oneConcern Over the Negative Consequences of Success items and found four factors. Our four factors show considerable overlap with dimensions based on theoretical accounts of
FOS etiology as well as with the factor structures obtained from two other factor analytic studies. Thus, there is converging
evidence that FOS is multidimensional. The relationship between multidimensional FOS and a multidimensional approach to achievement
motivation is discussed. 相似文献
39.
The manipulation of stimulus significance, by instructions from the experimenter, may be taken as an example of verbal conditioning. Consideration of such a mechanism suggested that personality effects previously found in conditioning studies should be apparent in instructional manipulations of significance in a study of the orienting response (OR) to words. Because of recent changes in dimensioning of the personality structure, some of the items originally used to define Eysenck’s extraversion (E) dimension are now used to assess the new dimension of psychoticism (P), suggesting that at least some of the established effects of E upon conditioning may be associated now with P. Hence the P scale was focused on in this study. Words differing on the evaluative dimension of the semantic differential were presented in three blocks, the first under indifferent instructions, the second under instructions to rate the words for their affective impact, and the third under indifferent instructions again. These blocks correspond to baseline, conditioning, and extinction conditions respectively. Electrodermal activity indicated enhanced conditioning, together with greater carry-over effects in the extinction phase, for low-P compared with high-P subjects. The results indicate the importance of personality effects in studies of stimulus significance and illustrate the value of the verbal conditioning mechanism in this area of the OR field. They also suggest the need to re-examine previously obtained E-effects in conditioning studies in light of changing personality tests. 相似文献
40.