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931.
Do alcoholic Korsakoff's syndrome patients acquire affective reactions?   总被引:1,自引:0,他引:1  
In this study we report two experiments that investigate the acquisition of affective reactions. In Experiment 1, unfamiliar melodies were played to Korsakoff's syndrome patients and alcoholic and nonalcoholic control subjects who were matched with them according to age and education. Following a retention interval of 5 min, subjects received a preference test on old and new melodies. Korsakoff's syndrome patients showed the same increase in preference for old melodies as a consequence of prior exposures as control subjects did, but their recognition of melodies was significantly impaired in comparison with controls. In Experiment 2, the same subjects saw photographs of two men. Fictional biographical information depicted one as a "good guy" and the other as a "bad guy." After a retention interval of approximately 20 days, Korsakoffs recalled virtually none of the biographical information; however, 78% preferred the good guy, and impression ratings were less favorable for the bad guy. Korsakoff patients developed preferences and impressions even though they did not have voluntary access to the information on which the preferences were based. However, their impression ratings were less extreme than those of controls. The pattern of results of the two studies is discussed in terms of Johnson's (1983) MEM model of memory.  相似文献   
932.
Effects of luminance and contrast on direction of ambiguous apparent motion   总被引:1,自引:0,他引:1  
S M Anstis  G Mather 《Perception》1985,14(2):167-179
A study is reported of the role of luminance and contrast in resolving ambiguous apparent motion (AM). Different results were obtained for the short-range (SR) and the long-range (LR) motion-detecting processes. For short-range jumps (7.5 min arc), the direction of ambiguous AM depended on brightness polarity, with AM only from white to white and from black to black. But for larger jumps, or when an interstimulus interval (ISI) was introduced, AM was less dependent on polarity, with white often jumping to black and black jumping to white. Two potential AMs were pitted against each other, one carried by a light stimulus and the other by a dark stimulus. The stimulus whose luminance differed most from the uniform surround captured the AM. Visual response to luminance was linear, not logarithmic. When the stimulus was modified to give continuous AM in one direction it was followed by a negative aftereffect of motion only when the spatial displacement was 1 min arc. A larger displacement (10 min arc) gave good AM but no motion aftereffect. Thus only short-range motion adapts motion-sensitive channels.  相似文献   
933.
Stephen  Timothy D.  Harrison  Teresa M. 《Sex roles》1985,12(1-2):195-206
The present study was designed to investigate the relationship experience of males and females who do not conform to sex-typical orientations to intimacy. One hundred sixty-three couples' and 88 nondating singles' (total N=414) responses to the Relationship World Index—Version 2 (RWI-2) were analyzed via discriminant analysis to determine if subjects' sex could be predicted accurately upon the basis of their RWI-2 scores. One discriminant function was found which was significant by the Wilks' lambda test [x2(60)=140.57, p<.001]; the procedure correctly classified 76% of the respondents. Those who were classified correctly were considered sex-typical and the remaining 24% of the sample was considered non-sex-typical in their orientations to intimacy. Additional analyses using data from a 6-month longitudinal study located qualities which significantly distinguished sex-typical from non-sex-typical subjects and couples in which at least one member was non-sex-typical from couples in which both members were classified as sex-typical.  相似文献   
934.
John M. McMaster 《Sex roles》1985,13(7-8):393-403
A structured questionnaire based on Rest's Defining Issues Test format was adopted to investigate the reasons used by 50 Black African males and 50 Black African females to explain their degree of acceptance of sex-role reversals. Both males and females showed little acceptance of sex-role reversals. The organization of the reasons they used to explain their degree of acceptance of sex-role reversals was most parsimoniously explained by Rest's complex stage model rather than the model suggested by Ullian, which is based on Piagetian stage criteria.  相似文献   
935.
The effects of dopaminergic depletion of the nucleus accumbens was tested in various behavioral tasks such as alternation, spatial discrimination, and reversal learning, and in an extinction paradigm in a T maze. Animals with lesions showed impairment of spontaneous alternation behavior, disturbances in the acquisition of spatial discrimination, and great difficulty in reversing previously learned habits. In the extinction phase, experimental animals are unable to adjust their behavior, and continue to choose the previously reinforced arm of the T maze. It is suggested that the nucleus accumbens plays an important role in the transition of motivation into action, and that dopamine has a facilitatory influence on the mediation of these processes.  相似文献   
936.
To test the generality, across modality and across species, of a bidirectional effect of photic stimulation in infant rats found in previous experiments, two experiments examined the effects on heart rate (HR) of onset and offset of auditory stimulation in rats and of photic stimulation in guinea pigs. Experiment 1 demonstrated a unidirectional, decelerative response in rats 17 and 21 days of age to the onset and offset of a 1-kHz tone, at both low (80 dB) and high (100 dB) intensity levels and at 14 days to the onset of the high-intensity tone. Experiment 2 demonstrated that infant guinea pigs, which unlike infant rats are precocial and not nocturnal, responded to the offset but not to the onset of light, and that this response was decelerative. These results indicated a lack of generality of the bidirectional HR effect, and were discussed in terms of the orienting/defensive reflex distinction.  相似文献   
937.
During 46 consecutive days the daily food intake and weight were recorded in 16 male Wistar rats. On Days 31-45 one mouse was presented each rat daily. Before any experience with mice (Days 0-27) the mousekiller rats, compared with the nonkiller rats, regulated their individual food intake more closely to their homeostatic equilibria, corrected for the linear trend. This result indicates a functional difference in food intake regulation between mousekiller rats and nonkiller rats prior to any experience with mice. However, no difference in the mean food intake was found between the mousekiller and the nonkiller rats.  相似文献   
938.
The effects on aggressive behavior, open-field activity, and pain threshold of bilateral microinjections of serotonin (20 micrograms) and quipazine (20 micrograms), the direct serotonergic receptor agonist, into the cortico-medial amygdala were investigated in Wistar rats. Both drugs significantly prolonged the attack latency in isolated killer rats (predatory aggression model), and suppressed the incidence of aggressive postures/attacks in shock-induced fighting test (affective aggression). The only difference in the open-field behavior was the lower number of central square entries in drug-treated compared to saline-injected rats. None of the substances produced any significant change in jump threshold. It is concluded that stimulation of serotonin receptors within the amygdala produces inhibition of affective and muricidal behavior in isolated rats. The effect does not seem to be dependent on changes in general activity and pain sensitivity.  相似文献   
939.
Individual differences in attribution have been little researched. Beliefs about locus of control have been taken to be stable and important differences between people. They may provide some of the background assumptions on which people base their explanations of actions, especially insofar as these explanations imply that the cause of an action was within the agent or his environment, and that the action was or was not under the agent's control. Respondents were therefore asked to fill in Rotter and Levenson locus of control questionnaires and to provide explanations or ask questions about several actions. It was hypothesized that internals would be inclined to go for explanations which were personal and implied high control, while externals would not. However, what emerged was the paradoxical finding that internals provided explanations which implied that the causes of the actions lay outside the agent, while externals provided ones which implied that the causes lay within. This result is discussed in terms of the difference between actions and outcomes, and the possibility that an important difference between people may be in the rigidity and simplicity of their beliefs about causality.  相似文献   
940.
The present study explored the factors that contribute to mothers' decisions to seek urgent medical attention for their children when symptoms are not of a traumatic nature. One hundred mothers seeking treatment for their children at a prepaid clinic completed a questionnaire eliciting their expectations regarding the course of their children's problems, seriousness of the problems, perceived responsibility for the symptoms, and extent to which a variety of factors contributed to their decisions to seek treatment. Demographic data and information about each child's symptoms and medical history were also obtained. Four major "reasons for seeking treatment" factors were identified: family history of the presenting complaint, worry regarding the symptoms, situational variables, and the extent of the child's illness behavior. The appropriateness of the visit, delay in seeking treatment, and frequency of mothers' use of the pediatric clinic were predicted by the nature of the presenting symptoms (particularly the presence of fever), the ages of the mother and child, and two of the reasons for seeking treatment factors (i.e., family history and child's illness behavior). The present study suggests that mothers pay more attention to presenting symptoms and to the children's behavior than to psychosocial stressors in deciding to seek urgent care.  相似文献   
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