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31.
Approximately 50% of all institutionalized, mentally retarded adults receive psychotropic medication to control inappropriate behavior. In this study, behaviors exhibited by five retarded adults were formally observed while they were on and off medication. Each subject had been receiving chlorpromazine for six or more years prior to the start of the study. The drug was withdrawn and readministered using a double-blind B-A-B (drug-placebo-drug) design. Effects were highly individualized. Some desirable behavior emerged when chlorpromazine was discontinued.  相似文献   
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General catastrophic thinking styles about uncomfortable bodily sensations may predispose the development of common health pathologies, such as persistent headache. The purpose of this research was to explore the relationships between the Pain Catastrophizing (PC) Scale and Anxiety Sensitivity (AS) Index, which measure tendencies to catastrophize pain- and anxiety-related somatic sensations, respectively. A non-clinical sample completed the PC Scale, AS Index, and health outcome questionnaires regarding headache (n = 1018). Results revealed that: (i) AS and PC are empirically separate constructs; (ii) the overlap between PC and AS lies within the domain of fearing physical catastrophe; (iii) AS independently predicts weekly headache, headache pain intensity, and the number of a wide range of physical symptoms associated with headache; and (iv) PC independently predicts the presence of weekly headache. Limitations and implications of this research, as well as recommendations for future research directions are discussed.  相似文献   
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We examined the ontogeny of the corticosterone response to (+)-methamphetamine in neonatal rats. In experiment-1, animals were injected with 10 mg/kg of (+)-methamphetamine or saline and plasma corticosterone levels were examined in separate groups 30 or 105 min later on postnatal day (P) 1, 3, 5, 7, 9, 11, 13, 15, 17, or 19. The adrenal response to methamphetamine was best described by a U-shaped function with the nadir of corticosterone release occurring between P7 and P13. Experiment-2 was similar except that the effect of four consecutive days of exposure to (+)-methamphetamine (four times daily at 2 h intervals with 10 mg/kg) was assessed with a single final dose early on the fifth day (i.e. P1-5, 3-7, 5-9, 7-11, 9-13, 11-15, 13-17, 15-19). The 30 min corticosterone response after multiple methamphetamine doses was augmented compared to single exposures, with the exception of the two earliest dosing intervals ending on P5 and P7, where the responses were lower. In addition, at 105 min, the levels of corticosterone were attenuated relative to a single drug administration. With the exception of animals receiving methamphetamine from P15 to P19, thymus weights were unaffected. The data demonstrate that (+)-methamphetamine is a robust activator of corticosterone release in developing animals and this release is extensively modified by age and previous drug exposure.  相似文献   
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OBJECTIVE: According to the American Psychiatric Association, 3% to 7% of the school-age population has ADHD and many children continue to display significant symptoms throughout adolescences and adulthood. Relative to the childhood literature, less is known about ADHD in adults, especially college students with ADHD. The principle purpose of this review articles is to summarize the major research findings concerning ADHD in the college student population with regard to prevalence of symptoms, neuropsychological and psychological functioning. Overall, findings suggest that college students with ADHD are at greater risk for academic and psychological difficulties, and they perform similar to non-ADHD controls on many neuropsychological tasks. These findings are preliminary, however, and are tempered by the small number of studies that have been conducted as well as the methodological limitations of these studies. CONCLUSION: Future research using larger sample sizes, rigorous assessment criteria, and a longitudinal design is needed to better understand the psychological, academic, and neuropsychological functioning of college students with ADHD. Studies are also needed to elucidate the effects of pharmacological and nonpharmacological effects of treatment on the functioning of college students with this disorder.  相似文献   
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The current investigations build upon previous ethnographic research, which identified a social norm for adolescent females to engage in “fat talk” (informal dialogue during which individuals express body dissatisfaction). In Study 1, participants were shown a vignette involving women engaging in fat talk dialogue and were subsequently asked to chose one of three self-presentational responses for a target female: (1) self-accepting of her body, (2) providing no information, or (3) self-degrading about her body. Male and female participants believed the target would be most likely to self-degrade, and that this would lead women to like her, while the self-accepting response would lead men to like her most. Study 2 used the same vignette but participants were asked to respond in an open-ended fashion. Participants again expected the target female to self-degrade. The present findings suggest college students perceive fat talk self-degradation of body image as normative.  相似文献   
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Curiously, studies using the remember/know paradigm to measure recollective experience show that people often vividly remember events that never occurred, a phenomenon referred to asillusory recollection. Two experiments tested the hypothesis that false remember responses in the converging associates, or Deese/Roediger-McDermott (DRM) paradigm, reflect accurate memory for the study episode, rather than false recollection of critical lures. To test this hypothesis, we used standard remember instructions that emphasized recollection of the study context by allowing participants to use memory of surrounding list items as evidence for recollection, or we used modified instructions that did not include memory for surrounding list items as a basis for recollection. Results showed that, as compared with the standard instruction condition, the modified instructions selectively reduced reports of false remember responses to critical lures, but did not affect remember responses to studied items. By contrast, remember responses to critical lures were unaffected by an instruction condition that excluded the use of voice information as evidence for remembering. These results suggest that remember responses to falsely recognized items are driven partly by retrieval of studied items, rather than illusory recollection of the critical lures themselves. They further point to the importance of instructions in influencing subjective reports.  相似文献   
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To measure people’s reaction times to the nearest millisecond, it is necessary to know exactly when a stimulus is displayed. This article describes how to display stimuli with millisecond accuracy on a normal CRT monitor, using a PC running Linux. A simple C program is presented to illustrate how this may be done within X Windows using the OpenGL rendering system. A test of this system is reported that demonstrates that stimuli may be consistently displayed with millisecond accuracy. An algorithm is presented that allows the exact time of stimulus presentation to be deduced, even if there are relatively large errors in measuring the display time.  相似文献   
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