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Most studies of suicide in younger patients have demonstrated significant alterations in the serotonin system. Although a high percentage of completed suicides occur in late-life, to date very few studies of the biology of suicide have focused on this age group. This chapter describes age-related changes in the central nervous system pertinent to the biology of suicide, then reviews post-mortem biological studies of the brains of suicides and suicide attempters. As suicide attempts in the elderly are characterized by the use of violent means, biologic studies of impulsive violence are discussed. Finally we describe data on the effect of degenerative diseases on the serotonin system and the possible link to increased suicidal behavior in affected patients. This review underscores the need for further study of the biology of suicide in the geriatric age group. 相似文献
53.
Parent–adolescent conflict has been studied both as a precursor of long-term macrolevel developmental risks and as an outcome of microlevel, moment-to-moment interaction patterns. However, the family-level processes underlying the maintenance or regulation of conflict in daily life are largely overlooked. A meso-level understanding of parent–adolescent conflict offers important practical insights that have direct implications for interventions. The present study explores day-to-day reciprocal processes and carryover in parents’ and adolescents’ experiences of anger and conflict. Daily diary data provided by parent–adolescent dyads (N = 151) from two-caregiver households (adolescents: 61.59% female, mean age = 14.60 years) over 21 days were examined using a multivariate Poisson multilevel model to evaluate the circular causality principle in parents’ and adolescents’ daily conflict and anger. Findings offer empirical support for the theory, suggesting that parents’ and adolescents’ anger and conflict exist together in a feedback loop wherein conflict is both a consequence of past anger and also an antecedent of future anger, both within and across persons. Increased understanding of the daily interaction patterns and maintenance of parent–adolescent conflict can guide more informed, targeted, and well-timed interventions intended to ameliorate the consequences of problematic parent–adolescent conflict sequences. 相似文献
54.
Parents who experienced infertility have increasingly used medically assisted reproduction (MAR) to add children to their families over the past few decades. These parents will need to decide if they will tell their children about being conceived using MAR. Although MAR information sharing operates within family contexts, little is known about the role of conversation orientation—one family contextual factor—in child outcomes associated with MAR information sharing in middle childhood. Derived from the Family Communication Patterns Theory, this study proposes that conversation orientation moderates the associations between MAR information sharing and children's psychosocial adjustment. This proposal was tested using a sample of 81 6- to 12-year-old MAR-conceived children from 55 families and a structured observational measure of conversation orientation. Multiple regression analyses showed that MAR information sharing interacted with conversation orientation to influence children's behavioral and attention problems but not emotional problems. In families with high conversation orientation, MAR information sharing was not significantly associated with children's behavioral and attention problems. In families with low conversation orientation, MAR information sharing was significantly associated with an increase in children's behavioral and attention problems. Results of this exploratory study demonstrate the potential significance of general communication orientation in understanding child outcomes of MAR information sharing and highlight the needed family context nuances in MAR research. 相似文献
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Relationship of anxiety and depression to age and sex in an acute psychiatric population 总被引:1,自引:0,他引:1
R E Correll 《Psychological reports》1984,55(3):979-986
57.
Convergent and divergent stereo mechanisms were compared in their ability to recover structure from motion. Contrary to a recent result reported by Richards and Lieberman, no difference in their performance was found; both mechanisms appeared equally capable of supporting the perception of good structure from motion. Possible reasons for the disparate results are discussed. 相似文献
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