Significant Within-group Effects Research Articles

A Longitudinal Study of the Impact on Young Children of Maternal HIV Serostatus Disclosure

A longitudinal analysis of the psychological well-being of 81 young children ages 6–11 living with their HIV symptomatic or AIDS diagnosed mothers was conducted. Specifically, the relationship among mothers’ disease severity, maternal disclosure of HIV, and children’s psychological well-being was investigated. The children were assessed over three time points (i.e. baseline assessment, 6- month and 1-year follow-up). Two categories of maternal disclosure (disclosed before baseline, no disclosure at any of the three time points over 1-year), and two categories of disease severity (< 500 T-cell count across all assessments, 500+) were created. A series of 2 × 2 × 3 repeated measures MANOVAs was used to assess the effects of the maternal disclosure and disease severity across time on children’s psychological well-being. Results showed significant within-group time effects for child depression, suggesting a decrease in depression over time. Interaction results of time and maternal disclosure revealed only a few significant changes over time. However, significant decreases over time for child depression were noted among children whose mothers’ CD4 cell counts remained at 500+ across the three assessment periods. Implications for future research and for psychosocial needs of these families are discussed.

Peripheral Pulses of Oxytocin Increase Partner Preferences in Female, but Not Male, Prairie Voles

Centrally administered oxytocin (OT) facilitates social behaviors including the partner preferences that characterize the monogamous social system of prairie voles. In contrast peripherally administered OT generally has been ineffective in influencing central processes including behavior. OT from the posterior pituitary gland is released in pulses into the peripheral circulation. We hypothesized that peripherally administered OT, if delivered in repeated injections mimicking these pulses, would influence behavior. Male and female prairie voles received three subcutaneous injections of OT, a single injection of OT, or isotonic saline. Animals then were placed with an adult member of the opposite sex, designated as a “partner,” for a 1-h period of cohabitation, and subsequently tested for preference for the familiar partner versus a comparable stranger. Females treated with pulses of peripheral OT (1, 5, or 20 μg) displayed a significant preference for the partner compared to control females, while females receiving a lower dose of OT (0.1 μg) or a single injection (20 μg) did not. There was also a significant within-group effect as pulsed OT-treated females spent more time with the partner when compared to the stranger, while control females spent equal amounts of time with the partner and stranger. Peripheral pulses of OT were no longer effective in inducing partner preferences when females were pretreated with a selective OT receptor antagonist, administered either peripherally or centrally. In contrast to females, peripheral treatment with OT did not facilitate the formation of partner preferences in males.