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The role played by the neonatal 5-hydroxytryptamine (5HT) system in the organization and sexual differentiation of adult agonistic behavior was investigated in rats. Focus was on the 5HT2 receptor subtype, which has been demonstrated to be involved in agonism control in the adult. 5HT2 activity was experimentally manipulated by administration of a specific agonist [1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane HCl (DOI)] or antagonist (ritanserin) during the second week of life, when serotonin is known to concur to anatomical and behavioral sexual differentiation. Interactions between early 5HT2 activity, genetic sex, and neonatal circulating testosterone (T) were studied by administering the ligands to males, females, and androgenized females. At adulthood, the animals were tested for both aspects of agonism, i. e., aggression and defense, in a 20-min confrontation with an unfamiliar conspecific of the same sex, age, body weight, and social experience. Neonatal administration of the 5HT2 antagonist ritanserin increased aggression independently of sex; it also increased defense, but this effect was confined to males. The agonist DOI had no effect on aggression, but enhanced defense in males and androgenized females, with an effect which depended therefore more on neonatal T than genetic sex. Females appeared in general less sensitive to neonatal 5HT2 manipulation than both androgenized females and males; this suggests that neonatal T is crucial for experimental modifications of neonatal 5HT2 activity to have any consistent effect on adult agonistic behavior. On the other hand, effects observed in males and androgenized females were dependent on the behavior considered and the drug administered. This was especially evident for defense, enhanced by ritanserin in males only, and in both males and androgenized females by DOI. Neonatal 5HT2 activity seems therefore to play a role in the modulation of adult agonistic behaviors, which depends on the behavior considered and is under multiple control of genetic sex and hormonal neonatal substrate. © 1994 Wiley-Liss, Inc.  相似文献   
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Sanders et al.'s proposal for a management framework for conflicting interests among program developers is very welcome. The underlying principles of such a framework must nevertheless prioritise the need for researchers and commissioners of services to make objective assessments of the impact of interventions reported in journal articles. This is particularly important in the field of randomised trials which may influence public sector expenditure. Using a strict definition derived from known financial conflict of interest, we have demonstrated that child-based effect sizes are much lower for independent studies than for studies with developer involvement. On this basis, we propose that journals publishing evaluations of psychosocial interventions should agree a standardised format for declarations of conflicts of interest based on that recommended by the International Committee of Medical Journal Editors.  相似文献   
105.
Children with autism spectrum disorder (ASD) who have limited speech are often taught to communicate using a speech-generating device (SGD). We evaluated procedures for teaching a mand for information (i.e., Where is [item]?) using an interrupted behavior chain procedure. In Experiment 1, all participants (3 children with ASD who communicated using an SGD) acquired the target mand but transfer to a novel stimulus did not occur. In the second experiment, 2 participants were taught to approach alternative communication partners when the first partner did not provide the information. The second experiment also included procedures to test whether the responses were under the control of appropriate motivating operations (MOs). Generalization across communication partners occurred with both participants, but transfer across behavior chains with only 1 participant. The results of both experiments suggest that teaching multiple behavior chains and evaluating MO control may be necessary to establish generalized manding for information.  相似文献   
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Married couples with a female agoraphobic spouse (n = 22) were compared with demographically similar community control couples (n = 21) on self-report and observational measures of marital interaction. Consistent with hypotheses, husbands of agoraphobic women were more critical of their wives than were control husbands, and clinical couples were less likely to engage in positive problem solution than control couples. Contrary to hypothesis, clinical husbands were not less supportive than control husbands. Where general measures of marital distress were concerned, clinical couples, relative to control couples, evinced more distress by self-report, by their higher rate of negative nonverbal behavior, and by their longer sequences of negative exchanges.  相似文献   
108.
This paper describes the relations of psychological distress with 11 ecological factors (5 community, 4 family, and 2 individual) among 423 older urban adolescents who are predominantly people of color. Data were obtained by means of self-report via group-administered questionnaires given between 1994 and 1996; most scales are multi-item. There is wide variation in distress. There are very few statistically significant relationships between the ecological factors and distress, and those are negligible. Girls whose parents have less education and live in extended families have higher distress; family and individual domains are correlated .04 and .03 with distress and the community domain .00, so this ecological model accounts for a mere 7%, of the common total variance in distress.  相似文献   
109.
The absence or diminution of light is potentially an anxiety-arousing situation for, perhaps, all of us. Even a cursory look at the origin myths of many cultures reveals the chaotic, destructive, and dangerous aspects of darkness. Additionally, language reflects the same qualities metaphorically and symbolically. Developmentally, the arrival of the darkness of evening potentially signals object loss and ego regression. But factors other than ubiquitous references to a consideration of light and darkness are relevant. Can it be that we are all at least prone to depression due in part to this factor? Questions regarding possible biological causes of depression are perhaps unanswerable at this time. Is the seratonin level really associated with depression and light deprivation? Research is as yet inconclusive. If a relationship exists, another question must be asked: Will certain psychological situations affect a person's seratonin production? The answer to this question of how depression is associated with biological causes is certainly beyond the scope of this paper. Yet the preceding case history reveals at least some psychological causes of depression that were initially seen as biologically based. The SAD proponents would have treated Mr. B with light therapy. The quick solution of light therapy, based on a shaky theoretical base and lacking sturdy research, has too often replaced the psychoanalytic approach. In all too many situations psychoanalysts are being replaced by lightbulbs.  相似文献   
110.
This study provides a comprehensive picture of age differences in self-esteem from age 9 to 90 years using cross-sectional data collected from 326,641 individuals over the Internet. Self-esteem levels were high in childhood, dropped during adolescence, rose gradually throughout adulthood, and declined sharply in old age. This trajectory generally held across gender, socioeconomic status, ethnicity, and nationality (U.S. citizens vs. non-U.S. citizens). Overall, these findings support previous research, help clarify inconsistencies in the literature, and document new trends that require further investigation.  相似文献   
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