Poster #5 - The Family Biorhythm: Contributions of the HPA and HPG Axes to Neuroendocrine Attunement

• In Event: Poster Session 07

Abstract

Background. Biobehavioral synchrony between infants and their caregivers is important for attachment and emotional development and is influenced by environmental factors such as social support (Hibel et al., 2018). The calibration of infant neuroendocrine function, including activity of the hypothalamic-pituitary-adrenal axis (HPAa), largely depends on biological attunement with parents (Del Giudice et al., 2011). Although there is substantial evidence for mother-infant physiological attunement, little work has been done on the family biorhythm, and research on paternal biobehavioral influences remains especially sparse. Fathers may contribute to infant developmental outcomes by promoting mother-infant bonds, including HPAa attunement (Clauss 2018). These physiological associations have rarely been studied within the mother-father-infant triad, and the impacts of other hormonal moderators of behavior in families remain largely unexplored, including the products of the hypothalamic-pituitary-gonadal axis (HPGa), namely progesterone, which is associated with dyadic affiliation and relationship quality (Edelstein et al., 2016). This study aims to increase understanding of paternal influences on the biobehavioral dynamics of the family unit, using a multi-system approach.

Methods. Participants include 32 families (32 mothers; 21 fathers, 32 infants) recruited during pregnancy from community prenatal clinics. Mothers completed monthly questionnaires on couple satisfaction (Couple Satisfaction Index, Funk & Rogge, 2007). Home visits were conducted when the infant reached 4-, 12-, and 18-months and included semi-structured interaction tasks and saliva samples (3 time points) for cortisol and progesterone assays.

Results. Linear mixed-effects models (LMEs) were used to account for time-varying covariates (salivary hormones), missing observations across time (4-, 12-, and 18-months), and to measure the hormone changes of dyads (mother-infant, mother-father, father-infant) across time points. Results indicated that mothers and infants, but not fathers and infants, showed adrenocortical attunement, with the strongest mother-infant attunement at 18 months (b = 1.23, SE = .22, p = .004). Mothers’ couple satisfaction was not associated with infants’ cortisol levels or mother-infant cortisol attunement, but mothers’ progesterone moderated the relationship between couple satisfaction and infant cortisol levels (b=.005, SE=.001, p=.001). Specifically, mothers with low couple satisfaction but high progesterone had infants with lower cortisol levels. Finally, mothers’ and fathers’ progesterone levels were attuned across the time points (b=.27, SE=.07, p<.001).

Discussion. Findings suggest that mothers are physiologically attuned to their infants, consistent with previous research (Ruttle et al., 2011), as well as to their partners. In contrast to previous work (Clauss et al., 2018), we did not find an association between satisfaction within the parental relationship and maternal-infant adrenocortical attunement. We did find, however, that maternal progesterone moderated the relationship between couple satisfaction and infant cortisol such that mothers with lower couple satisfaction but higher progesterone had infants with lower cortisol. This suggests that progesterone plays a role in regulating affiliative behavior in the context of lower social support. To the extent that HPGa coordination reflects psychosocial synchrony, synchrony within couples may facilitate responsive caregiving to their infants, setting in motion a cascade of behavioral coordination mediated by neuroendocrine responses. In this way, fathers may play an indirect role in the establishment of mother-infant attunement.

Authors

• Lucia Ciciolla, Oklahoma State University - Stillwater
  Presenting Author

• Erin Wood, University of Illinois at Urbana-Champaign

• Ray Garza, Oklahoma State University-Stillwater

• Nikki Clauss, University of Texas Health Science Center at San Antonio

• Jennifer Byrd-Craven, Oklahoma State University