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831.
The effect of sound on visual apparent movement   总被引:1,自引:0,他引:1  
Twelve subjects found the longest possible interstimulus interval (ISI) at which they perceived continuous apparent motion of one light instead of partial motion or succession between two lights. In the visual condition, two lights only were presented. In the bimodal conditions, binaurally presented tones were presented synchronously with the lights, and the lights and tones were either spatially congruent (in phase) or incongruent (180 degrees out of phase). Bimodal presentations lowered the upper ISI threshold for the perception of visual apparent motion, and the reduction was greater when the tones and lights were spatially congruent. The threshold reduction may be caused by a perceptual inference about localization of the lights in space or by a change in visual persistence.  相似文献   
832.
833.
The Menstrual Symptom Questionnaire was administered to initial and cross-validation samples of college-age women. Factor analyses performed on the data from each sample failed to support Dalton's distinction between spasmodic and congestive forms of primary dysmenorrhea. Instead, a more complicated factor structure evolved, closely resembling Webster's findings, with factors representing menstrual pain, pre-menstrual negative affect, pre-menstrual water retention, pre-menstrual pain, menstrual backache and menstrual gastrointestinal symptoms. Oral contraceptive use was negatively related to menstrual pain and backache. Neuroticism scores were positively related to all six factors, and negative life changes to four of these factors, suggesting a role for psychogenic factors in both pre-menstrual and menstrual symptomatology.  相似文献   
834.
de Silva and Rachman (1981) have recently suggested that although non-reinforced exposure of a fear-evoking stimulus constitutes a sufficient condition for unlearning fears, it does not represent a necessary condition. This conclusion was reached, in part, by examples they provide which appeared to them to suggest that fear-reduction can occur in the absence of exposure to the fear stimulus. They then call for an extended search for non-exposure types of intervention, especially those involving ‘sources of information’ and ‘expectations’. After reviewing in detail the arguments advanced, the present authors adopt the position that de Silva and Rachman's conclusions are premature and unwarranted. To abandon or lose sight of one of the most effective and perhaps most important therapeutic principles, CS exposure, would be myopic and detrimental to the advancement of effective behavior change. At this point in time what is needed is a more careful analysis of the extinction process especially at the stimulus level so the effectiveness of this principle can be maximized.  相似文献   
835.
Twenty-six agoraphobics were randomly assigned to either Paradoxical Intention (PI) or Self-Statement Training (SST) which consisted of 12 weekly 90-min group sessions with 4–5 patients per group. Major assessments were carried out at pre-treatment, 6th week and 12th week of treatment, and at 1- and 6-month follow-ups. Measures included clinical ratings of severity of condition, phobia, anxiety and depression. Furthermore, a behavioral test was administered during which changes in subjective units of discomfort and cognitions were assessed. The results indicated statistically-significant improvement over time with both treatments. ANCOVAs performed revealed superior effects on several agoraphobia measures for the PI condition at post-treatment. However, by the 6-month follow-up assessment, the groups were equivalent due to marked improvement during the follow-up phase in the SST condition. Cognitive changes were marked by a decrease in self-defeating statements without concomitant increase in coping statements. These results and recommendations for future research are discussed.  相似文献   
836.
Certain reliable findings from research on directed forgetting seem difficult to accommodate in terms of the theoretical processes, such as selective rehearsal or storage differentiation, that have been put forward to account for directed-forgetting phenomena. Some kind of "missing mechanism" appears to be involved. In order to circumvent the methodological constraints that have limited the conclusions investigators could draw from past experiments, a new paradigm is introduced herein that includes a mixture of intentional and incidental learning. With this paradigm, a midlist instruction to forget the first half of a list was found to reduce later recall of the items learned incidentally as well as those learned intentionally. This result suggests that a cue to forget can lead to a disruption of retrieval processes as well as to the alteration of encoding processes postulated in prior theories. The results also provide a link between intentional forgetting and the literature on posthypnotic amnesia, in which disrupted retrieval has been implicated. With each of these procedures, the information that can be remembered is typically recalled out of order and often with limited recollection for when the information had been presented. It therefore was concluded here that retrieval inhibition plays a significant role in nonhypnotic as well as in hypnotic instances of directed forgetting. The usefulness of retrieval inhibition as a mechanism for memory updating was also discussed.  相似文献   
837.
The role of marking when reward is delayed   总被引:1,自引:0,他引:1  
Two-choice spatial discrimination by rats is enhanced if a salient stimulus marker occurs immediately after every choice response and again after a delay interval (Lieberman, McIntosh & Thomas, 1979). Three experiments further explore this effect. Experiment 1 found that the second marker is unnecessary. Experiment 2 found that a marker presented before a response is as effective as one presented after. Both effects could be explained in terms of markers focusing attention on subsequent cues. Experiment 3, however, found that markers after choice enhance learning even when no discriminative cues are present following the marker. Markers thus appear to initiate both a backward search through memory and attention to subsequent events; both processes help to identify events that might be related to the unexpected marking stimulus.  相似文献   
838.
An experiment is reported designed to test the hypothesis that female rats might discriminate between males that differed in the quantity of odor deposited by scent marking. Male odor donors were selected by prior screening for high or low rates of scent marking in an open arena. Females were then tested to determine whether they showed any preference for males that marked at a high rate. It was found that female rats did discriminate, but that they preferred to remain near males selected for low rates of scent marking.  相似文献   
839.
Impaired retention of an inhibitory avoidance response was observed in rats subjected to adrenalectomy (ADX) up to 120 hr before the single learning trial. Corticosterone substitution failed to normalize this behavioral deficit. Rats ADX 240 hr prior to the learning trial showed a normalized behavior. Adrenomedullectomy (ADXM) 48 or 240 hr before learning caused a similar impairment as in short-term ADX rats. The 240-hr ADX rats subjected to corticosterone substitution showed the same behavioral deficit as short-term ADX rats or ADXM ones. Immediate postlearning subcutaneous injection of adrenaline in a dose range of 0.005-5.0 micrograms/kg or of noradrenaline (0.005-0.5 microgram/kg) to 48-hr ADX rats resulted in a dose-related improvement of later retention behavior. Higher doses of catecholamines were less or ineffective. Postlearning treatment of 48-hr ADXM rats with adrenaline (0.5-500 micrograms/kg) caused a similar pattern of behavioral changes. It is concluded that adrenal catecholamines play an important role in the modulation of consolidation of memory. In addition, the high circulating ACTH levels that follow long-term ADX may correct for the behaviorial deficit induced by the absence of adrenomedullary catecholamines.  相似文献   
840.
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