UEL Baby Dev Lab

Measuring the temporal dynamics of inter-personal neural entrainment in continuous child-adult EEG hyperscanning data

I.Marriott Haresign, E.A.M.Phillips, M.Whitehorn, L.Goupil, V.Noreika, V.Leong, S.V.Wass 2022. Developmental Cognitive Neuroscience

Current approaches to analysing EEG hyperscanning data in the developmental literature typically consider interpersonal entrainment between interacting physiological systems as a time-invariant property. This approach obscures crucial information about how entrainment between interacting systems is established and maintained over time. Here, we describe methods, and present computational algorithms, that will allow researchers to address this gap in the literature. We focus on how two different approaches to measuring entrainment, namely concurrent (e.g., power correlations, phase locking) and sequential (e.g., Granger causality) measures, can be applied to three aspects of the brain signal: amplitude, power, and phase. We guide the reader through worked examples using simulated data on how to leverage these methods to measure changes in interbrain entrainment. For each, we aim to provide a detailed explanation of the interpretation and application of these analyses when studying neural entrainment during early social interactions.

Gaze onsets during naturalistic infant-caregiver interaction associate with ‘sender’ but not ‘receiver’ neural responses, and do not lead to changes in inter-brain synchrony

I. Marriott Haresign, E.A.M Phillips, M. Whitehorn, F. Lamagna, M. Eliano, L. Goupil, E.J.H. Jones, S.V. Wass 2022. bioRxiv

Temporal coordination during infant-caregiver social interaction is thought to be crucial for supporting early language acquisition and cognitive development. Despite a growing prevalence of theories suggesting that increased inter-brain synchrony associates with many key aspects of social interactions such as mutual gaze, little is known about how this arises during development. Here, we investigated the role of mutual gaze onsets as a potential driver of inter-brain synchrony. We extracted dual EEG activity around naturally occurring gaze onsets during infant-caregiver social interactions in N=55 dyads (mean age 12 months). We differentiated between two types of gaze onset, depending on each partner's role. 'Sender' gaze onsets were defined at a time when either the adult or the infant made a gaze shift towards their partner at a time when their partner was either already looking at them (mutual) or not looking at them (non-mutual). 'Receiver' gaze onsets were defined at a time when their partner made a gaze shift towards them at a time when either the adult or the infant was already looking at their partner (mutual) or not (non-mutual). Contrary to our hypothesis we found that, during a naturalistic interaction, both mutual and non-mutual gaze onsets were associated with changes in the sender, but not the receiver's brain activity and were not associated with increases in inter-brain synchrony above baseline. Further, we found that mutual, compared to non-mutual gaze onsets were not associated with increased inter-brain synchrony. Overall, our results suggest that the effects of mutual gaze are strongest at the intra-brain level, in the 'sender' but not the 'receiver' of the mutual gaze.

Applying gaze-contingent training within community settings to infants from diverse SES backgrounds

Ballieux, H., Wass, S., Tomalski, P., Kushnerenko, E., Karmiloff-Smith, A., Johnson, M., & Moore, D. 2016. Journal of Applied Developmental Psychology

Even in infancy children from low-SES backgrounds differ in frontal cortex functioning and, by the start of pre-school, they frequently show poor performance on executive functions including attention control. These differences may causally mediate later difficulties in academic learning. Here, we present a study to assess the feasibility of using computerized paradigms to train attention control in infants, delivered weekly over five sessions in early intervention centres for low-SES families. Thirty-three 12-month-old infants were recruited, of whom 23 completed the training. Our results showed the feasibility of repeat-visit cognitive training within community settings. Training-related improvements were found, relative to active controls, on tasks assessing visual sustained attention, saccadic reaction time, and rule learning, whereas trend improvements were found on assessments of short-term memory. No significant improvements were found in task switching. These results warrant further investigation into the potential of this method for targeting ‘at-risk’ infants in community settings.

Anxious parents show higher physiological synchrony with their infants

Smith, C., Jones, E., Charman, T., Clackson, K., Mirza, F., & Wass, S. 2019. Psychological Medicine

Background
Interpersonal processes influence our physiological states and associated affect. Physiological arousal dysregulation, a core feature of anxiety disorders, has been identified in children of parents with elevated anxiety. However, little is understood about how parent–infant interpersonal regulatory processes differ when the dyad includes a more anxious parent.

Methods
We investigated moment-to-moment fluctuations in arousal within parent-infant dyads using miniaturised microphones and autonomic monitors. We continually recorded arousal and vocalisations in infants and parents in naturalistic home settings across day-long data segments.

Results
Our results indicated that physiological synchrony across the day was stronger in dyads including more rather than less anxious mothers. Across the whole recording epoch, less anxious mothers showed responsivity that was limited to ‘peak’ moments in their child's arousal. In contrast, more anxious mothers showed greater reactivity to small-scale fluctuations. Less anxious mothers also showed behaviours akin to ‘stress buffering’ – downregulating their arousal when the overall arousal level of the dyad was high. These behaviours were absent in more anxious mothers.

Conclusion
Our findings have implications for understanding the differential processes of physiological co-regulation in partnerships where a partner is anxious, and for the use of this understanding in informing intervention strategies for dyads needing support for elevated levels of anxiety.

Parental frontal brain activity tracks infants’ attention during shared play

Wass, S., Marriott-Haresign, I., Whitehorn, M., Clackson, K., Georgieva, S., Noreika, V., & Leong, V. 2020. PsyArXiv

Previous research has suggested that similar patterns of neural activity occur between watching someone else perform an action and performing it oneself. Here, we demonstrate a comparable phenomenon: that, while engaged in free-flowing naturalistic parent-child play, parents’ oscillatory activity recorded overfrontal areas co-varies with their infants’ attention patterns, independent of their own attention patterns. We also found weaker evidence for the opposite relationship: that infants’ brain activity tracks adults’ attention. We demonstratethis by recording dual EEG in 12-month-old infants and their parents while they were engaged in joint and solo tabletop play with toys, andanalysing the time-lagged temporal associations between infants’ attention towards play objects and adults’ neural activity, and vice versa. We discuss how these inter-dyadic brain-behaviour correspondences relate to actor-observer relationships previously been documented, and consider their role asdriversof inter-personal neural synchrony.