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991.
McCarty CA Rhew IC Murowchick E McCauley E Vander Stoep A 《Psychology of addictive behaviors》2012,26(2):351-357
This study aimed to evaluate whether emotional health factors, including anxiety and depression, stress, and social support, are associated with earlier youth initiation of alcohol and illicit substances during middle school (from the sixth to the eighth grade). Data for this study were from the Developmental Pathways Project, a longitudinal study of 521 youth sampled from the Seattle Public Schools. Discrete time survival analyses were used to assess the effects of depression, anxiety, stress, and support on initiation of substance use, measured every 6 months at five time points between sixth and eighth grade. Youth who had initiated prior to sixth grade had significantly higher levels of depressive symptoms. In multivariate survival analyses controlling for child race/ethnicity, gender, and socioeconomic status, and accounting for conduct problems, youth who reported higher levels of separation anxiety/panic symptoms were at decreased risk for early alcohol initiation. Children with higher levels of perceived teacher support had a significantly lower risk of alcohol initiation during early follow-up periods. Recent stressful life events in Grade 6 were associated with significantly greater risk of initiating an illicit substance by Grade 8. The current findings highlight the role of stress in the initiation of illicit substance use and suggest that teacher support is associated with lower risk for very early alcohol use. Future research examining anxiety as a predictor of substance use should distinguish between subtypes of anxiety. 相似文献
992.
Giving difficult news to patients represents a common dilemma for health care professionals. Based on three decades of research, various authors have proposed guidelines outlining the ideal setting, delivery, and timing. Existing publications focus on patients of European descent and may not be applicable in cross-cultural settings. We explored perceptions of Spanish-speaking mothers who have a child with Down syndrome and how they preferred to receive the news of their child's diagnosis. We conducted semi-structured qualitative interviews (n?=?14), which were coded and analyzed by thematic networks to identify common themes. Six significant themes emerged: Cultural Belief System, Communication, Support/Lack of Support, Feelings Engendered, Medical Issues, and Medical System. One overarching theme of mother-child bonding encompassed all sub-themes. The mothers desired the news in a more positive, balanced light and with more complete explanations about the condition. Mothers felt excluded from the diagnostic process and wanted to be better informed about the need for diagnostic studies. Participants used religious beliefs to explain the reason for their child's condition. Many factors influenced Latina mothers' ability to bond initially with their children with Down syndrome. Ideally, these factors should be acknowledged during informing interviews to assist Latino families in adjustment. 相似文献
993.
Previous work on social support and stress tolerance using laboratory-based cardiovascular stress response paradigms has suggested that perceived social support may be effective in building resilience in recipients. However, such paradigms are often socially de-contextualized insofar as they fail to take account of the social aspects of stress itself. Using 90 healthy college women, the present study sought to examine the association between self-reported perceived social support and cardiovascular stress tolerance. Participants underwent two consecutive exposures to a mental arithmetic task. On second exposure to the stressor, participants completed the task under either social threat or control conditions. Social threat was manipulated using socially salient instructions, to create a high social context. Adaptation to stress was established in terms of comparisons between cardiovascular responses to successive exposures. Results showed that cardiovascular responses tended to habituate across time, with perceived social support associated with the degree of habituation, but only under certain contextual conditions; high perceived support was associated with effective habituation under control conditions only. This response pattern is consistent with the view that high perceived social support buffers against stress in healthful ways, but only in asocial contexts. 相似文献
994.
Post-acquisition release of glutamate and norepinephrine in the amygdala is involved in taste-aversion memory consolidation 总被引:1,自引:0,他引:1
Guzmán-Ramos K Osorio-Gómez D Moreno-Castilla P Bermúdez-Rattoni F 《Learning & memory (Cold Spring Harbor, N.Y.)》2012,19(6):231-238
Amygdala activity mediates the acquisition and consolidation of emotional experiences; we have recently shown that post-acquisition reactivation of this structure is necessary for the long-term storage of conditioned taste aversion (CTA). However, the specific neurotransmitters involved in such reactivation are not known. The aim of the present study was to investigate extracellular changes of glutamate, norepinephrine, and dopamine within the rat amygdala using in vivo microdialysis during the acquisition and 1-h post-acquisition of CTA paradigm. Microdialysis monitoring showed a significant norepinephrine increase related to novel taste exposure and a glutamate increase after gastric malaise induction by i.p. LiCl administration. Interestingly, we found a spontaneous concomitant increase of glutamate and norepinephrine, but not dopamine, 45 min after conditioning, suggesting the presence of aversive learning-dependent post-acquisition signals in the amygdala. These signals seem to be involved in CTA consolidation process, since post-trial blockade of N-methyl-D-aspartate or β-adrenergic receptors impaired long- but not short-term memory. These data suggest that CTA long-term storage involves post-acquisition release of glutamate and norepinephrine in the amygdala. 相似文献
995.
This paper presents a study examining whether self-efficacy and intrinsic motivation are related to environmentally responsible behavior (ERB). The study analysed past environmental behavior, self-regulatory mechanisms (self-efficacy, satisfaction, goals), and intrinsic and extrinsic motivation in relation to ERBs in a sample of 156 university students. Results show that all the motivational variables studied are linked to ERB. The effects of self-efficacy on ERB are mediated by the intrinsic motivation responses of the participants. A theoretical model was created by means of path analysis, revealing the power of motivational variables to predict ERB. Structural equation modeling was used to test and fit the research model. The role of motivational variables is discussed with a view to creating adequate learning contexts and experiences to generate interest and new sensations in which self-efficacy and affective reactions play an important role. 相似文献
996.
Sexual attraction was considered a component of sexual orientation from the beginning of the second half of the 20th century to present times. However, some recent researchers have studied sexual attraction as an independent field measuring it by the Sexual Attraction Questionnaire (SAQ). This study analyzes sexual attraction through the SAQ in 400 university students from a Peruvian catholic university. These participants -191 women and 209 men- show a very diverse curricular background. The following hypotheses were tested: a) the structure of the SAQ, pointing out two concepts: attraction to men and attraction to women; b) the high inverse correlation between these two concepts or factors; c) the specific impact of this context in sexual attraction: higher percentage of attracted by none of the sexes and lower percentage of attracted to the opposite sex, in comparison with other contexts; and d) the Lippa prediction (2006, 2007), regarding a higher polarization of sexual attraction for men than for women. Results support the first three hypotheses. Clarifications are laid down with regard to the fourth one. Discussion focuses on theoretical and applied advantages of using the SAQ as opposed to the frequent use of a single item of sexual attraction for each sex. 相似文献
997.
Benetti F da Silveira CK da Silva WC Cammarota M Izquierdo I 《Neurobiology of learning and memory》2012,97(1):54-58
Early partial maternal deprivation causes long-lasting neurochemical, behavioral and brain structural effects. In rats, it causes a deficit in memory consolidation visible in adult life. Some of these deficits can be reversed by donepezil and galantamine, which suggests that they may result from an impairment of brain cholinergic transmission. One such deficit, representative of all others, is an impairment of memory consolidation, clearly observable in a one-trial inhibitory avoidance task. Recent data suggest a role of brain histaminergic systems in the regulation of behavior, particularly inhibitory avoidance learning. Here we investigate whether histamine itself, its analog SKF-91844, or various receptor-selective histamine agonists and antagonists given into the CA1 region of the hippocampus immediately post-training can affect retention of one-trial inhibitory avoidance in rats submitted to early postnatal maternal deprivation. We found that histamine, SKF-91844 and the H2 receptor agonist, dimaprit enhance consolidation on their own and reverse the consolidation deficit induced by maternal deprivation. The enhancing effect of histamine was blocked by the H2 receptor antagonist, ranitidine, but not by the H1 receptor antagonist pyrilamine or by the H3 antagonist thioperamide given into CA1 at doses known to have other behavioral actions, without altering locomotor and exploratory activity or the anxiety state of the animals. The present results suggest that the memory deficit induced by early postnatal maternal deprivation in rats may in part be due to an impairment of histamine mediated mechanisms in the CA1 region of the rat hippocampus. 相似文献
998.
Villarejo C Fernández-Aranda F Jiménez-Murcia S Peñas-Lledó E Granero R Penelo E Tinahones FJ Sancho C Vilarrasa N Montserrat-Gil de Bernabé M Casanueva FF Fernández-Real JM Frühbeck G De la Torre R Treasure J Botella C Menchón JM 《European eating disorders review : the journal of the Eating Disorders Association》2012,20(3):250-254
999.
Since modernity, the concept of subject supposes both an anthropocentric and a dualistic view of life and reality. In this study, we carry out an analytic interpretation of the Descartes’ notion of subject, in order to build a different dimension of the concept of subject. We discuss the activity of computing, as the manner by which the living subject relates with and in-forms the world. We further examine computing in the aging yeast as an example of living subject and we try to comprehend the maturity of the subjectivity in Descartes’ res cogitans and in our proposed res computans. 相似文献
1000.
An experiment was conducted using a human instrumental learning task with the goal of evaluating the mechanisms underlying the deleterious effect of context-switching on responding to an unambiguous stimulus when contexts are informative to solve the task. Participants were trained in a context-based reversal discrimination in which two discriminative stimuli (X and Y) interchange their meaning across contexts A and B. In context A, discriminative stimulus Z consistently announced that the relationship between a specific instrumental response (RI) and a specific outcome (O1) was in effect. Performance in the presence of stimulus Z was equally deteriorated when the test was conducted outside the training context, regardless of whether the test context was familiar (context B) or new (context C). This result is consistent with the idea that participants code all the information presented in an informative context as context-specific with the context playing a role akin to an occasion setter. 相似文献