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281.
This study is one in a series investigating the relationship between impulsive behavior on a Continuous Performance Test (i.e., the Immediate and Delayed Memory Task) and other cognitive deficits measured by clinical instruments. Forty-two adolescents were selected for two groups, controls and hospitalized patients with disruptive behavior disorders. Each adolescent completed the Immediate and Delayed Memory Task and the Benton Visual Retention Test. Our main findings were that, even when controlling for IQ, the Immediate and Delayed Memory Task commission errors were associated with adverse Benton performance, but only in the patient group. These results may be explained by a shared association between processes of impulsivity and other deficits of executive control that may interfere with successful performance of the Benton.  相似文献   
282.
Studies of the hypothalamic-pituitary-adrenal (HPA) axis in persons with posttraumatic stress disorder (PTSD) have produced variable findings. This review focuses on the factors likely to have affected the outcome of these studies, including population characteristics and experimental design. Also discussed is a possible role for the adrenal neurosteroid dehydroepiandrosterone (DHEA) as a mediator of HPA axis adaptation to extreme stress and the psychiatric symptoms associated with PTSD. The antiglucocorticoid properties of DHEA may contribute to an upregulation of HPA axis responses as well as mitigate possible deleterious effects of high cortisol levels on the brain in some PTSD subpopulations. The neuromodulatory effects of DHEA and its metabolite DHEAS at gamma-aminobutyric acid and N-methyl-D-aspartate receptors in the brain may contribute to psychiatric symptoms associated with PTSD. The possible importance of other neurohormone systems in modulating HPA axis and symptom responses to traumatic stress is also discussed. Understanding the complex interactions of these stress-responsive neurosteroid and peptide systems may help explain the variability in patterns of HPA axis adaptation, brain changes, and psychiatric symptoms observed in PTSD and lead to better targeting of preventive and therapeutic interventions.  相似文献   
283.
The literature contains inconsistent data on the effects of acute sleep deprivation on the superior cognitive functions. The primary purpose of this study is to determine the effectiveness of inhibition, one of the functions of the working memory executive centre (EC), over an extended, 36-hour waking period. Inhibition is a cognitive mechanism whereby individuals ignore non-relevant information recorded in their working memory. We also tested the effects of a 36-hour period of acute sleep deprivation on simple reaction time. Twelve young, healthy volunteers (M = 21.5 years, sigma = 2.3) performed a random generation task involving letters and a simple reaction time psychomotor test over four sessions held at 10-hour intervals. Each participant was assigned a "constant routine." Participants were kept awake in a prone position within a room whose environment was held strictly constant (light, noise, temperature, meals, etc.). This control procedure provided assurance that any variation in participant performance was solely caused by sleep deprivation. The random generation task, nearly two minutes in length, consisted in verbally producing a sequence of 100 letters in a random fashion (i.e. by inhibiting, for example, alphabetical order) and by keeping to a set rhythm. Our assumption was that capacity for inhibition diminished as the number of hours of sleep deprivation increased. The simple reaction test, 10 minutes in length, involved pressing a button as swiftly as possible to cause a black square to disappear from a screen. In this case our assumption was that acute sleep deprivation alters simple reaction time. Analysis of variance (ANOVA) through repeated measures using the "sessions" factor as an intra-subject variable showed no significant changes in randomization indices of the random generation task, contrary to analysis of average simple reaction times. Participants' reaction times deteriorated over the first two minutes of the test during the night they were deprived of sleep. It would seem that the contradictory results of previous studies of the effects of acute sleep deprivation on the inhibition function would be due to errors in factor identification. In conclusion, the inhibition function, as measured during the performance of a brief task, seems to remain intact during an extended, 36-hour waking period. Simple reaction time assessed by means of a brief psychomotor test is affected during a night of sleep deprivation. The working-memory inhibition executive function shows greater resistance to acute sleep deprivation than does psychomotor reaction time for the performance of short tasks.  相似文献   
284.
Social identity theory (SIT) proposes that the more strongly individuals identify with their group, the less favorable attitudes they hold toward dissimilar groups. In contrast, multicultural theory proposes that affirmation toward one's group--particularly with respect to ethnicity--should correspond with higher levels of acceptance toward dissimilar groups. These competing theories were examined with 486 non-Hispanic White, African American, and Hispanic/Latino university students to determine if support would be found for either theory. Consistent with SIT, levels of ethnic identity correlated significantly with levels of ethnocentrism for Whites and Hispanics but not for African Americans. African Americans obtained significantly higher ethnic identity and self-esteem scores than the other 2 groups. Implications of the findings are discussed.  相似文献   
285.
Psychoanalysis has struggled with issues of touching and being touched, and of holding and being held, since Freud's early essays toward "taking hold" of elusive thoughts through various means. More recently, observations of early dyadic interchanges between caretaker and child have illuminated how facets of the analytic process, such as the quality of gaze, tone, or empathic resonance, affect feelings of "being held" within the object world. These studies interplay with other analytic depictions and the work of affect theorists to show how meanings become represented and manifested over time through verbal versus nonverbal means. The author uses this literature to explore how our capacity to receive and transmit information cross-modally creates an interpenetration of meanings between self and other in the absence of actual physical contact. Clinical illustrations explore some of the meanings and uses of nonphysical modes of touch within the analytic environment.  相似文献   
286.
Seventy-three college students participated in a study to assess the role of self-efficacy and imperatives in social anxiety. The students were asked to speak in front of a small group of their peers and their anxiety and length of time talking were measured. Neither lower self-efficacy nor higher levels of imperative thinking at Baseline were correlated with higher levels of anxiety. The critical finding was that subjects who showed higher levels of imperative thinking at Baseline spoke for a significantly shorter period of time. This suggests that the participant's anxiety was moderated by the performance of an instrumental response, in this situation by choosing to limit the amount of time spent talking. The results suggest the centrality of imperative thinking in shaping behavior in the domain of social anxiety.  相似文献   
287.
288.
Anxiety Symptomatology in Mexican-American Adolescents   总被引:3,自引:0,他引:3  
Mexican-American adults and adolescents in general have been reported to have high levels of anxiety symptomatology. In our study of a tri-ethnic sample of 2528 junior and senior high school students, the Youth Self Report (YSR) version of the Child Behavior Checklist (CBCL) and a sociodemographic questionnaire was used to assess the anxiety symptoms of Hispanic youth. We compared the ratings on anxiety symptoms, using Achenbach's anxiety subscale on the YSR, between two populations. The anxiety levels of youth in coastal southeast Texas (Galveston County) were compared to the anxiety levels of youth in the lower Rio Grande Valley. We found that Mexican-Americans of the Lower Rio Grande Valley scored higher on anxiety symptoms than the tri-ethnic population of Galveston County. Other factors associated with higher anxiety scores for Mexican-American youths included being born outside the US, linguistic fluency, father absent from the home, mother's education, and household size. Multiple regression analyses showed that socio-economic status (SES), family composition, and linguistic fluency had a greater relative impact on anxiety symptomatology than all other factors, both for the total sample as well as for the Mexican-American sample. These results parallel previous findings, with Mexican-American adults, which suggest either higher risk for anxiety symptomatology or a culturally related bias in the reporting of such symptoms.  相似文献   
289.
Taking time seriously. A theory of socioemotional selectivity   总被引:25,自引:0,他引:25  
Socioemotional selectivity theory claims that the perception of time plays a fundamental role in the selection and pursuit of social goals. According to the theory, social motives fall into 1 of 2 general categories--those related to the acquisition of knowledge and those related to the regulation of emotion. When time is perceived as open-ended, knowledge-related goals are prioritized. In contrast, when time is perceived as limited, emotional goals assume primacy. The inextricable association between time left in life and chronological age ensures age-related differences in social goals. Nonetheless, the authors show that the perception of time is malleable, and social goals change in both younger and older people when time constraints are imposed. The authors argue that time perception is integral to human motivation and suggest potential implications for multiple subdisciplines and research interests in social, developmental, cultural, cognitive, and clinical psychology.  相似文献   
290.
Nonstrategic subjective threshold effects in phonemic masking   总被引:1,自引:0,他引:1  
Three backward-masking experiments demonstrated that the magnitude of the phonemic mask reduction effect (MRE) is a function of subjective threshold and that the magnitude is also independent of stimulus-based response strategies. In all three experiments, a target word (e.g., bake) was backward masked by a graphemically similar nonword (e.g., BAWK), a phonemically similar nonword (e.g., BAIK), or an unrelated control (e.g., CRUG). Experiments 1 and 2 had a low percentage (9%) of trials with phonemic masks and differed only in baseline identification rate. Experiment 3 controlled baseline identification rate at below and above subjective threshold levels, with 9% phonemic trials. The results were that identification rates were higher with phonemic masks than with graphemic masks, irrespective of the low percentage of phonemic trials. However, the magnitude of the phonemic MRE became large only when the baseline identification rate was below subjective threshold. The pattern of the phonemic MRE was interpreted as a result of rapid automatic phonological activation, independent of stimulus-based processing strategies.  相似文献   
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