Brains in Synch: Using Neuroimaging to Study Parent-Infant Interaction

• In Event: Understanding Dyadic Biobehavioral Synchrony: Developmental Precursors and Functions

Abstract

Background. Altricial mammals have a biological predisposition to respond to social distress calls (i.e. crying). Crying infants actively and instinctively seek and maintain their caregiver’s proximity and care, and caregivers also instinctively seek and respond to their infants. In human and other non-human primates (i.e. marmosets) these early caregiver-infant interactions give rise to caregiver-infant bonding, which shapes brain development influencing physiological and psychological processes throughout the lifespan. A potential avenue of investigating the caregiver-infant relationship lies in caregiver-infant synchrony, which refers to the coordinated interplay of behavioral and physiological signals reflecting the bi-directional attunement of one individual to another’s psychophysiological, cognitive, emotional and behavioral state.
Objective. We aim to study how early naturalistic caregiver-infant interactions give raise to caregiver-infant attachment, which influences physiological and psychological processes by modulating brain sensitivity. Furthermore, we aim to study how caregiver-infant bond shapes neural pathways involved in socio-emotional regulation.
Methods. Different experiments, employing different methodologies (fMRI, fNIRS, TMS) in humans (N = 135) that draw parallels with findings from animal studies, were used to investigate the interrelations between genetic, hormonal, and environmental factors in caregiver-infant interactions across different cultural contexts. Additionally, we will focus on new evidence from fNIRS hyperscanning studies, where we measured simultaneous caregiver (mother (N=29) and father (N=36) and child brain activity (N=65). In the hyperscanning studies, the caregiver and child went through two different tasks together: watching a series of animated video clips, and engaging in a joint free play session with a set of standardized toys.
Results/Conclusions. From the mother-child hyperscanning study (Azhari et al., 2019), we have found that higher levels of parenting stress experienced by the parent is correlated to lower mother-child brain-to-brain synchrony, especially in the areas of the medial left prefrontal cortex. Additionally, maternal anxious attachment (Azhari et al., 2020a) also correlated in lower mother-child synchrony in the frontal and medial left prefrontal regions. These areas contain structures implicated in the inference of mental states and social cognition, highlighting the role of psychological factors such as parenting stress and attachment style in the influence of caregiver-infant bond formation during naturalistic interactions.
From the combined mother- and father-child free play sessions (Azhari et al., 2020b), behavioural data revealed that parenting stress and caregivers’ recall of their past bonding experiences their own parents interact with each other to influence the eventual quality of dyadic interaction with their child. Specifically, parenting stress is moderated by recalled maternal overprotection, and this relationship is predictive of the level of non-hostility shown by the caregiver during free play.
In conclusion, bond formation is influenced by multiple systems, including environmental factors, as well as parenting and genetic factors, such as vulnerability to risk factors and temperament. Current approaches to the study of caregiver-infant attachment should consider its multi-level nature, from the individual psychological processes to the broader environmental and social contexts within which the caregiver and infant interact.

Author

• Gianluca Esposito, University of Trento
  Presenting Author