Biobehavioral Synchrony and Hormonal Correlates of Parenting from Pregnancy to Toddlerhood: A Longitudinal, Multi-Method Study of First-Time Fathers and Mothers

Abstract:

Psychological, hormonal, and neural adaptations during the transition to parenthood shape early caregiving behaviors and may set the course for children’s long-term socioemotional and physical health. A growing body of research highlights biobehavioral synchrony, the coordination of behavioral and neural responses between caregivers, as a key mechanism supporting early family functioning. However, little is known regarding how biobehavioral synchrony between parents emerges during pregnancy, how it evolves through infancy and toddlerhood, and how it may contribute to child outcomes. This K99/R00 project addresses these gaps by investigating father–mother biobehavioral synchrony in the prenatal period, its role in shaping early caregiving, and its subsequent associations with postnatal triadic biobehavioral synchrony and child health-related outcomes. Using a novel, multi-method approach, the project will integrate functional near-infrared spectroscopy (fNIRS) and microanalytic coding to assess neural and behavioral synchrony. In addition, salivary hormone assays (cortisol reactivity and testosterone) during structured family interactions will measure hormonal changes. During the proposed K99 training phase, a small pilot sample of ~10 expectant couples will complete prenatal neural, hormonal, and behavioral assessments and be followed postnatally at 8 months as triads, providing an opportunity to refine the multi-method protocol, assess feasibility, and gain hands-on training in all study procedures. Building on this foundation, the R00 phase will scale the study to ~80 families assessed at four time points: prenatally, and at 8, 20, and 30 months postpartum. The project is guided by three aims: (1) pilot assessments of prenatal father–mother neural and behavioral synchrony and hormonal reactivity; (2) test longitudinal associations between prenatal dyadic synchrony and postnatal triadic synchrony, caregiving behaviors, and parent–child interactions; and (3) examine how pre- and postnatal synchrony and hormonal reactivity may shape children’s socioemotional functioning and health-related behaviors. By incorporating both parents and focusing on the prenatal emergence of synchrony, this proposal advances current models of family systems and child health. It also supports NICHD’s mission by identifying modifiable, biologically embedded processes that promote healthy family relationships and child outcomes. I will receive interdisciplinary training in fNIRS (Dr. Koraly Pérez-Edgar), hormonal analysis (Dr. Darby Saxbe), microanalytic behavioral coding of interparental and parent–child interactions (Dr. Natasha Cabrera), and intensive longitudinal modeling (Dr. Zachary Fisher). My training plan includes graduate-level coursework, advanced statistics workshops, a salivary data collection and assay bootcamp, and hands-on experience conducting neural, hormonal, and behavioral data collection. Together, this training—supported by an outstanding team of mentors—will prepare me to launch an independent, translational research program focused on biobehavioral dynamics in early family development and child health.