Longitudinal patterns of neuroendocrine coupling from middle childhood to early adolescence.

Recent scholarship has highlighted the importance of understanding relations between hormones, rather than studying hormones in isolation. Considering neuroendocrine coupling, or the coordination of hypothalamic-pituitary-adrenal axis and hypothalamic-pituitary-gonadal axis hormones over time, is one way to investigate how systems governing stress responsiveness and pubertal development covary during critical periods. To date, however, most work has considered hormone coupling cross-sectionally. The current study investigated neuroendocrine coupling in a longitudinal sample from the Northeastern United States. Youth (N = 437, 53% male, 90% White) provided saliva samples for analysis of diurnal hormone activity at ages 9 (three samples per day across 3 days) and 12 (one sample per day on the same weekday for 4 weeks). At both timepoints, samples collected 30-min after waking were assayed for cortisol, dehydroepiandrosterone (DHEA), and testosterone. Multilevel growth modeling was used to determine how levels of morning cortisol changed in tandem with DHEA and testosterone. Morning cortisol-DHEA coupling varied by child sex, as males' cortisol-DHEA diminished over time, especially among pubertally advanced males. Females, in contrast, demonstrated strengthening cortisol-DHEA coupling over time, especially more pubertally advanced females. Morning cortisol-testosterone coupling did not vary by sex or pubertal status, demonstrating strengthening associations between ages 9 and 12. The current findings contribute to the literature on hormone coupling across development and expand this work into an earlier developmental phase than previously investigated.