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71.
Potentiation and overshadowing in preweanling and adult rats   总被引:1,自引:0,他引:1  
Four experiments compared the aversion acquired by 18-day-old and 60-day-old rats to a flavor that was either tasted alone or in combination, simultaneously or successively, with another flavor when paired with illness. The purpose was to study temporal variables and theoretical issues pertinent to potentiation and overshadowing while investigating ontogenetic differences in these phenomena. When either the preweanlings or the adults were presented a simultaneous compound flavor (sucrose/coffee) followed by lithium chloride-induced illness, greater sucrose aversions were found than for animals conditioned on sucrose alone--that is, potentiation. Preweanlings demonstrated greater potentiation than did adults, whether the conditioned stimulus-unconditioned stimulus (CS-US) delay was 0 or 1 hr. This potentiation was eliminated by nonreinforced presentations of the alternative CS element. Potentiation was not seen when the two flavors were presented successively as the CS; instead, overshadowing occurred. Tests of configuring by extinction procedures indicated a tendency for these animals to form a configured representation of the simultaneous compound solution. This disposition for configuring tended to be more pronounced for preweanlings than for adults. Ontogenetic differences in response to configuration, CS saliency, and generalization decrement seem consistent with at least one model of potentiation and the ontogenetic differences in potentiation seen in the present experiments.  相似文献   
72.
This article reviews studies on the relation between social motives and susceptibility to physical illness. The motives examined in the studies include power motivation and affiliation motivation and their related syndromes such as inhibited power and relaxed affiliation. The subject populations include college students as well as adults. Blood pressure, self-reports of illnesses, catecholamines, and parameters of immunologic functioning are among the indices of health outcomes investigated. Taken together, these studies suggest that social motives may be importantly related to susceptibility to illness, that the power motive may be related to heightened susceptibility to illness, particularly when the person is under stress, whereas the affiliation motive may be related to diminished susceptibility to illness.  相似文献   
73.
The present study examined the similarities between four auditory adaptation techniques to determine whether the effects were correlated. The four adaptation techniques compared were: Simultaneous Dichotic Loudness Balance technique (SDLB; Hood, 1950), Magnitude Estimated Binaural technique (MEB; Botté, Canévet, & Scharf, 1982), Magnitude Estimated Monaural technique, (MEM; Weiler, Sandman, & Pederson, 1981), and the Monaural Reaction Time technique (RT; Davis & Weiler, 1976). Results did not show significant correlations between the four techniques, except (r = 0.39) between MEB and MEM procedures. This correlation was much less than the reliability of the measures would allow (r = 0.98 and r = 0.99, respectively). Thus, it appears that the different methods either produced different adaptation effects or measured different aspects of auditory adaptation. The normal ear apparently shows several forms of adaptation, which reduces the perceptual strength of a continuing stimulus, in favor of an intermittent, less redundant one.  相似文献   
74.
The effects of anxiety management training were evaluated by allocating 66 generally anxious clients to either a wait list condition, non-directive counselling, or a combination of relaxation and brief cognitive therapy. Anxiety management was significantly more effective than the wait list condition on a number of relevant measures at post-treatment, but there were relatively few differencs between anxiety management and non-directive counselling, either at post-treatment or at 6 months follow-up. Those differences which were found could plausibly be explained in terms of the demand characteristics of training in relaxation or cognitive therapy. It was concluded that anxiety management is clearly better than a non-treatment control condition, but that its superiority to plausible alternatives which lack the specific components thought to be responsible for improvement has yet to be demonstrated.  相似文献   
75.
In this study we combined daily diary data with interview data to investigate individual differences in the impact of stressful daily events on mood. Using a sample of 96 women in an urban community, we examined perceived neighborhood quality and major life events as possibly potentiating the effects of stressful daily events, and we viewed social supports as potentially buffering this daily process. Results confirmed that the presence of chronic ecologic stress (neighborhood perceptions) exacerbated the immediate effects of stressful daily events on mood and also increased the likelihood of enduring effects of daily stressors on next day's mood. Contrary to expectations, previous exposure to major life events decreased the impact of stressful daily events. The availability of social supports, although not buffering the impact of stressful daily events on mood, did mitigate the enduring effects of these events on next day's mood. This study also presents a method for analyzing daily time-series data, while correcting for potential problems of autocorrelated error terms. As such, this study represents a significant advance over previous analytic approaches to time-series data in the study of the stress process.  相似文献   
76.
The influence of sexual experience on preference behavior was investigated in adult female rats. In the first experiment, preference behavior for sexually active males versus estrous females was investigated in female rats who were experienced with mounting behavior. Preference of these mount experienced females was compared to preference of females who were naive in this respect. Mount experience with estrous females induced a female-directed preference in ovariectomized female rats, irrespective of whether the females were treated with OIL or with testosterone-propionate (500 micrograms TP, injected once 48 h prior to testing). Sexually naive, OIL-treated females did not show a preference for males or females, but TP induced a preference for a male. Individual differences in mount frequency were not correlated with preference behavior. In the second experiment, the influence of experience with feminine sexual responses on preference behavior was investigated. OIL-treated and TP-treated females oriented equally toward males and females when they had been given the opportunity to copulate with males prior to the preference tests. The results strongly suggest that prior sexual experience is an important determinant of preference behavior. The female's behavior during sexual interactions was, however, not predictive of later preference.  相似文献   
77.
This study compared the predictive validity of two types of overall assessment center ratings (clinical and mechanical) and two types of performance ratings (supervisor and subordinate). Data were gathered on approximately 50 law enforcement agency managers over a four-year time span. Results indicated that clinical predictions were not significantly better than mechanical ones and that prior performance ratings were better predictors of future performance ratings than were assessment centers. Further, dimension ratings within the assessment center were found to be unrelated to ratings of the same dimensions on the job four years later, supporting the notion of subtle criterion contamination (Klimoski & Strickland, 1977) and raising questions about the central assumptions underlying the assessment center approach.  相似文献   
78.
79.
This article deals with appropriate communication and interpersonal skills that nurses may use in order to support patients who are experiencing self-concept changes related to their health problems. Three areas of patient need related to self-concept are explored. The stages of adaptation to loss and the crucial task of grief work are reviewed, and nursing interventions designed to strengthen the self-concept and support patients as they adapt to loss are suggested. Sensitive communication, although a low-visibility nursing skill, is cited as critical in assisting the patient to achieve an optimum level of wellness.  相似文献   
80.
REMINISCENCES,YOU SAY?   总被引:2,自引:2,他引:0       下载免费PDF全文
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