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391.
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The prevalence of postural orthostatic tachycardia syndrome (POTS) in adolescents and young adults has been increasing during the past decade. Despite this increase, documentation regarding treatment of these patients is just beginning to emerge. In addition, despite a call for a multidisciplinary or interdisciplinary approach, no studies have examined the efficacy of such an approach to treatment. This paper describes a case study of a 19-year-old male with debilitating POTS seen at a tertiary clinic for evaluation and subsequent intensive interdisciplinary treatment. The treatment approach is described and outcomes are presented.  相似文献   
394.
Swiss-Webster mice living in a visible burrow system (VBS) reacted to presentation of a live cat in the surface area of the VBS by retreat to the burrows and reductions in nondefensive behaviors such as eating and drinking. Live eat-exposed subjects remained in the burrows 14 hr or more, while subjects exposed to a toy (plush) cat prior to live cat exposure reemerged almost immediately and made many contacts with the toy cat. However, subjects exposed first to the cat and later to a toy cat showed intermediate surface reemergence times and cat contacts during toy cat tests, indicating strong sensitization effects of prior live cat exposure. Previous studies indicated that rats in this situation show retreat to the burrows, surface avoidance, and reduction in nondefensive behaviors. The mouse pattern was similar, with the notable exception that in the first 5min block after cat presentation, mice rapidly alternated retreat to the burrow chambers with reappearance in the tunnel segment near the surface, to scan the surface visually and sniff. Movement during this time block involved a stretch attend posture characteristic also of risk assessment activities in rats. Such visual and olfactory inspection of the cat is not seen in rats in the VBS. This difference may be related to the finding that rats, but not mice, emit ultrasonic “alarm cries” during and after cat exposure. © 1995 Wiley-Liss, Inc.  相似文献   
395.
To estimate frequencies of behaviors not carried out in public view, researchers generally must rely on self‐report data. We explored 2 factors expected to influence the decision to reveal: (a) privacy (anonymity vs. confidentiality) and (b) normalization (providing information so that a behavior is reputedly commonplace or rare). We administered a questionnaire to I55 undergraduates. For 79 respondents, we had corroborative information regarding a negative behavior: cheating. The privacy variable had an enormous impact; of those who had cheated, 25% acknowledged having done so under confidentiality, but 74% admitted the behavior under anonymity. Normalization had no effect. There were also dramatic differences between anonymity and confidentiality on some of our other questions, for which we did not have validation.  相似文献   
396.
Previous experiments have demonstrated that presenting independently established discriminative stimuli in compound can substantially increase operant responding maintained by food reinforcement or shock avoidance. Recently, this phenomenon was also shown to occur with cocaine self-administration. The present study further assessed the generality of these stimulus-compounding effects by systematically replicating them with heroin self-administration. Rats' nose-poke responses produced intravenous heroin (0.025 mg/kg per infusion) on a variable-ratio schedule when either a tone or a light was present. In the absence of these stimuli, responding was not reinforced. Once discriminative control by the tone and light had been established, the stimuli were presented in compound under extinction (with heroin discontinued) or maintenance conditions (with heroin available during test-stimulus presentations). In extinction, the tone-light compound increased responding approximately threefold compared to tone or light alone. Under maintenance conditions, compounding increased heroin intake approximately twofold. These effects closely matched those obtained earlier with cocaine. This consistency across pharmacological classes and across drug and nondrug reinforcers further confirms that (a) self-administered drugs support conditioning and learning in a manner similar to that supported by other reinforcers; and (b) multiple drug-related cues interact in lawful and predictable ways to affect drug seeking and consumption.  相似文献   
397.
In an attempt to determine whether hypnotically induced affect could be reliably discriminated from simulations, three hypnotically trained female undergraduate subjects were presented with posthypnotic cues to either experience or simulate varying degrees of anxiety and pleasure. Facial expressions generated by subjects in response to these cues were recorded on videotape and coded by means of the Facial Action Coding System (FACS). It was hypothesized that simulated emotional expressions, requiring greater cortical processing, would be marked by longer onset latencies and greater irregularity or fluctuation in muscular contraction than the presumably automatic changes in facial behavior accompanying posthypnotic emotions. Statistical analyses confirmed both expectations. The results were viewed as reflecting support for the validity of posthypnotically cued affect.  相似文献   
398.
To determine whether a "children-of-holocaust-survivors syndrome" could more parsimoniously be explained as an "immigration effect," we performed a comparative study on a sample of 25 children of holocaust survivors, 25 children of immigrants, and 25 children of American-born parents. Subjects were matched on age and educational level and were assessed with four measures of mental health. Contrary to the findings of some researchers whose data supported such a syndrome, our data indicate no significant differences between children of holocaust survivors and the children of other immigrants. These data are suggestive of an immigration effect that is common to the children of immigrants and not limited to the children of holocaust survivors, rather than a survivors syndrome. The children of American-born parents showed greater alienation, less religiosity, and a tendency toward feelings of less guilt than the other two groups. Our data underscore the need to control immigrant status in multiple samples and studies before definitive conclusions can be drawn in this area.  相似文献   
399.
The hypothesis that subsatiating levels of internal food stimuli can arouse and potentiate feeding behavior was examined in the mollusc Aplysia californica. Animals were fed a small quantity of seaweed and their latencies to show biting responses were determined after food arousal was permitted to partially decay. Control animals were stimulated with food, but were not permitted to ingest it, or were fed nonnutritive glass-fiber filter paper. Compared to controls, animals that were fed showed significantly shorter latencies to respond when tested up to 80 min after previous exposure to food. These results indicate that internal stimuli can function like external stimuli to enhance responsiveness to food and suggest the hypothesis that satiation may be viewed as an interactive process involving the interplay of excitatory and inhibitory influences arising from the alimentary system.  相似文献   
400.
In Experiment 1, a light and a tone were correlated independently with water reinforcement of bar pressing by rats. With different naive subjects in Experiment 2, one of these stimuli was correlated with food and the other with water reinforcement (counterbalanced). In both experiments the absence of tone and light signaled extinction. Tests of stimulus-reinforcer independence in Experiment 2 indicated that tone and light controlled behavior whose rate was specifically affected by deprivation state. In the stimulus-compounding tests of both experiments, response rates were higher to tone-plus-light than to tone or light presented alone (additive summation). This is the first report of additive summation produced through compounding stimuli paired with different reinforcers. The results are discussed in the context of the effects of incentive motivation on operant performance.  相似文献   
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