The results suggest that short-term testosterone administration enhances cognitive function in healthy older men. However, it remains unclear whether these improvements in cognition are attributable to increased testosterone or estradiol levels, or both. The potential role of testosterone vs its metabolites on cognition requires further research.

Background-Adolescence has been identified as a critical period with regard to the initiation and early escalation of alcohol use. Moreover, research on familial risk and protective processes provides independent support for multiple domains of parental influence on adolescent drinking; including parents' own drinking behaviors, as well as the practices they employ to socialize their children. Despite this prevalence of findings, whether and how these distinct associations are related to one another is still not entirely clear.

No abstract

These results confirm that elevated insulin without hyperglycemia enhances memory in adults with AD, and indicate that insulin is essential for hyperglycemic memory facilitation. These results also suggest a potential therapeutic role for somatostatin in AD.

Context As we identify genes involved in psychiatric disorders, the next step will be to study how the risk associated with susceptibility genes manifests across development and in conjunction with the environment. We describe analyses aimed at characterizing the pathway of risk associated with GABRA2, a gene previously associated with adult alcohol dependence, in a community sample of children followed longitudinally from childhood through young adulthood. Objective To test for an association between GABRA2 and trajectories of externalizing behavior from adolescence to young adulthood and for moderation of genetic effects by parental monitoring. Design Data were analyzed from the Child Development Project, with yearly assessments conducted since that time. A saliva sample was collected for DNA at the 2006 follow-up, with a 93% response rate in the target sample. Growth mixture modeling was conducted using Mplus to identify trajectories of externalizing behavior and to test for effects of GABRA2 sequence variants and parental monitoring. Setting Nashville and Knoxville, Tennessee, and Bloomington, Indiana. Participants A community-based sample of families enrolled at 3 sites as children entered kindergarten in 1987 and 1988. Analyses for the white subset of the sample (n=378) are reported here. Main Outcome Measures Parental monitoring measured at 11 years of age; Child Behavior Checklist youth reports of externalizing behavior at ages 12, 14, 15, 16, 17, 19, 20, 21, and 22 years. Results Two classes of externalizing behavior emerged: a stable high externalizing class and a moderate decreasing externalizing behavior class. The GABRA2 gene was associated with class membership, with subjects who showed persistent elevated trajectories of externalizing behavior more likely to carry the genotype previously associated with increased risk of adult alcohol dependence. A significant interaction with parental monitoring emerged; the association of GABRA2 with externalizing trajectories diminished with high levels of parental monitoring. Conclusions These analyses underscore the importance of studying genetic effects across development and of identifying environmental factors that moderate risk.

Higher fasting plasma insulin levels and reduced CSF-to-plasma insulin ratios, suggestive of insulin resistance, have been observed in patients with Alzheimer’s disease (AD) who do not possess an apolipoprotein E (APOE)-Ε4 allele. We examined the relationship of APOE and gender to peripheral insulin action and hyperinsulinemic memory facilitation in patients with AD using a sensitive measure of insulin-mediated glucose disposal. Participants were 32 patients with AD (9 without an Ε4 allele, 23 with an Ε4 allele) and 25 healthy age-matched adults (16 without an Ε4 allele, 9 with an Ε4 allele). AD subjects without an Ε4 allele had significantly lower insulin-mediated glucose disposal rates than AD patients with an Ε4 allele (p < 0.03), or than normal adults without an Ε4 allele (p < 0.02). Female AD subjects showed lower insulin-mediated glucose disposal rates than did male AD subjects (p < 0.02). No significant interaction was observed between APOE group and gender, suggesting that these effects are independent. AD subjects without an Ε4 allele also showed significant memory facilitation in the hyperinsulinemic condition (p < 0.04), whereas the AD-Ε4 group did not. Also in the hyperinsulinemic condition, AD patients without an Ε4 allele had lower insulin levels than patients with an Ε4 allele (p < 0.02), and women with AD had lower insulin levels than did men with AD despite similar insulin infusion rates and body mass (p < 0.004). No gender or genotype effects were observed in either condition for normal subjects. These results provide in vivo evidence of differences in insulin-mediated energy metabolism between Ε4 and non-Ε4 AD, and suggest that defective insulin action may be of particular pathophysiologic significance for patients without an Ε-4 allele.

Among adolescents, many parenting practices have been associated with the initiation and development of drinking behaviors. However, recent studies suggest discrepancies in parents’ and adolescents’ perceptions of parenting and their links with adolescent use. In this study, we derive two independent sets of underlying parenting profiles (based on parent and adolescent reported behaviors at age 11–12 years), which were then examined in relation to adolescents’ drinking behaviors at ages 14 and 17½. Results indicated that the two sets of profiles accounted for little shared variance, with those based on adolescents’ reports being stronger predictors of adolescent drinking. Moreover, comparisons of drinking levels across profiles pointed to multiple parenting strategies that may effectively reduce adolescent alcohol experimentation, including simply sustaining a moderate level of awareness of adolescents’ whereabouts and activities, and avoiding excessive conflict and strictness.

This study was focused on contextual variations in the parenting dimensions salient for preadolescent adjustment. The sample consisted of 614 sixth graders from two communities, one low and the other high income. Parenting dimensions included those known to be significant in each socioeconomic context: isolation from parents emotional and physical!, and parents' emphasis on achievements~overall expectations and emphasis on integrity over success!. Adjustment outcomes included subjective well-being as well as school competence. Contradicting stereotypes, results showed that on average, very affluent children can perceive their parents as emotionally and physically unavailable to the same degree that youth in serious poverty do. The ramifications for adjustment also seem to be largely similar: Closeness to parents was beneficial for all, just as criticism was deleterious. Even after considering the quality of parent-child relationships, parents' physical absence~e.g., at dinner! connoted vulnerability for distress and for poor school performance in both groups. The connotations of a few parenting dimensions varied by context and gender; these variations are discussed as are overall implications for future research and practice.