Resting-State Functional Connectivity of the Maternal Brain: Associations with Postpartum Timing and Maternal Structuring

• In Event: 3-077 - Multimodal Neuroimaging Approaches to Studies of Maternal Brain Adaptation: Parenting, Life Adversity and Psychopathology

Integrative Statement

In the postpartum period, the maternal brain experiences both structural and functional plasticity (Kim, Strathearn, & Swain, 2016; Lonstein, Lévy, & Fleming, 2015). The postpartum period has been shown to be associated with gray matter structural change (Kim et al., 2010), and greater postpartum months has been shown to be associated with greater cortical thickness in superior frontal and orbitofrontal regions (Kim, Dufford, & Tribble, 2018). However, the association between postpartum timing and resting-state functional connectivity (FC) remains unclear. Further, as structural and functional variations in maternal brain circuitry are hypothesized to support maternal behaviors (Lonstein et al., 2015), it is critical to examine the association between resting-state FC in the postpartum period with maternal behavior. Maternal structuring refers to a parent’s ability to support learning and exploration without overwhelming the child’s autonomy; maternal structuring also increases a child’s receptivity to learning (Biringen, 2000) and is related to several infant outcomes (Howes & Hong, 2008; Ziv, Gini, Guttman, & Sagi, 1997). However, the association between maternal structuring and FC during the postpartum period remains unclear.
In this study, we used resting-state fMRI to examine the relationship between later postpartum months and resting-state FC in the brain. We chose the amygdala as a seed region for FC analysis as evidence suggests its functional importance for maternal behaviors in the postpartum period (Champagne et al., 2004; Haim, Sherer, & Leuner, 2014; Kim et al., 2010; Lonstein et al., 2015; Swain et al., 2014). We recruited a sample of 47, socioeconomically diverse, first-time mothers with singleton pregnancies and obtained resting-state scans. For the left amygdala, later postpartum months were associated with greater connectivity with the anterior cingulate cortex (ACC), left nucleus accumbens (NAc), and right caudate (p < 0.05, FDR corrected, see Figure 1). For the right amygdala, later postpartum months were associated with greater connectivity with the bilateral caudate (see Figure 1). Further, FC between the left amygdala and left NAc was associated with greater maternal structuring during a mother child-interaction (r = 0.29, p < 0.05, Figure 1).
Overall, results provide evidence of relationships between later postpartum months and FC in the regions involved in salience detection and regions involved in reward/motivation; specifically, amygdala-NAc activity has a positive association with maternal structuring behavior. The amygdala and ACC are part of the salience network (Menon, 2015; Seeley et al., 2007), a higher-order system necessary for goal-directed behaviors (Menon, 2015). Thus, greater salience network FC may support salience detection and mothers’ response to infant cues, thus facilitating proper caregiving behavior (Corter & Fleming, 1995; Kim et al., 2016; Lonstein et al., 2015). Greater FC was also found between the left amygdala and left NAc and left caudate; further, left amygdala – left NAc FC had a positive relationship with maternal structuring. Thus, study findings with this sample of diverse, first-time mothers indicate a relationship between the postpartum period, resting-state FC, and maternal behaviors. Results provide a foundation for studies to examine these associations in clinical populations such as women experiencing postpartum depression or anxiety.

Authors

• Alexander Dufford, University of Denver
  Presenting Author

• Andrew J Erhart, University of Denver
  Non-Presenting Author

• Pilyoung Kim, University of Denver
  Non-Presenting Author