Frontal electroencephalogram (EEG) asymmetry reactivity: Exploring changes from baseline to still face procedure response

Abstract

Electroencephalogram (EEG) asymmetry has been widely studied across the lifespan, with multiple studies conducted in infancy. However, few have investigated frontal EEG asymmetry in the context of emotional-eliciting tasks, controlling for baseline to focus on an experimental episode response. The present study was designed to address this gap in research, predicting frontal EEG asymmetry response in the context of the Still Face procedure (SFP), examining mother–infant interaction quality and infant temperament attributes as potential contributors. Moderation by infant temperament was also considered. Results indicated that intensity and tone of parent–child interactions as well as Surgency/Positive Affectivity (and component scales of Approach and Activity Level) predicted frontal EEG asymmetry during SFP, controlling for baseline. Importantly, moderation was noted for Surgency/Positive Affectivity and its Approach component, reflected in significant interaction terms and follow-up simple slope tests. That is, the effect of intensity in mother–infant interactions was qualified by child overall surgency, and approach more specifically – infants demonstrating higher levels of Surgency/Positive Affectivity and Approach in particular were protected from the right frontal EEG response to SFP noted in the context of intense concurrent exchanges with mothers.

Development and validation of the Mindful Parenting in Infancy Scale (MPIS)

“…Results of the SEM analysis provided support for this association, with higher levels of mindfulness contributing to greater left frontal activation in the context of a mild stressor. This pattern of results, observed controlling for infant sex, age, and baseline asymmetry, also speaks to the protective role of caregiver mindfulness, as relative left frontal activation is generally interpreted as indicative of approach emotions/motivation, as well as regulation efforts and resilience (Curtis & Cicchetti, 2007; Gartstein, 2019), especially in the context of responding to a challenging situation (Coan et al, 2006).…”

“…The second SFP trial is a standard option commonly employed (DiCorcia et al, 2016; Handal et al, 2017; Lowe et al, 2017) since the initial publication documenting this procedural adaptation (Haley & Stansbury, 2003). The second trial of SFP was initially introduced to facilitate the assessment of physiological responsiveness (e.g., cortisol levels) in the context of a challenging situation and was leveraged to collect EEG data herein (Gartstein, 2019). SFP began with the experimenter instructing the mother to play with her infant utilizing stacking cups (provided by the experimenter) for 2 minutes and then to display a “still face” (i.e., emotionless, flat facial expression) for an equivalent duration (or stopping after 15 seconds of hard crying), refraining from any vocal expressions.…”

“…Briefly, left frontal EEG asymmetry is associated with approach, positive affect, and resilience, whereas relative right frontal activation is thought to provide neurophysiological basis for negative affect and withdrawal‐related emotions/motivation (Curtis & Cicchetti, 2007; Hane et al, 2008; Reznik & Allen, 2018). Parenting/parent–child interactions have been linked with asymmetry (Hane & Fox, 2006; Swingler et al, 2014), including in the context of the Still Face procedure (Gartstein, 2019).…”

Consistency of EEG asymmetry patterns in infants of depressed mothers

“…There were no specific requirements about the acceptable minimum amount of artifact‐free EEG in some infant frontal EEG asymmetry publications (e.g., Diego et al., 2006; Jones et al., 2009; Smith et al., 2016). Among others that applied a threshold, the cut‐off point was highly inconsistent, varying from 5 s to 60 s (e.g., Gartstein, 2020; Howarth et al., 2016; Schmidt, 2008). More reports assessing the reliability of infant resting and task EEG with differing amounts of artifact‐free data are needed to guide future research.…”

Electroencephalogram frontal asymmetry changes during emotion‐eliciting tasks and parent–child interaction dynamics

“…The second SFP trial is a standard option commonly employed (e.g., DiCorcia, Snidman, Sravish, & Tronick, 2016;Handal et al, 2017;Lowe et al, 2017) since the initial publication documenting this procedural adaptation (Haley & Stansbury, 2003). The second trial of SFP was initially introduced to facilitate the assessment of physiological responsiveness (e.g., cortisol levels) in the context of a challenging situation, and was leveraged to collect EEG data herein (Gartstein, 2019).…”