EEG Hyperscanning: Maternal-Newborn Neural Activation in Response to Skin-to-Skin Affectionate Touch
Poster No:
2532
Submission Type:
Abstract Submission
Authors:
Grace Kromm1, Kelly Pammenter2, Andrea Edwards2, Stanimira Georgieva3, Mohammed Adnan Azam3, Victoria Leong3, Topun Austin2
Institutions:
1University of Cambridge, Cambridge, United Kingdom, 2Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom, 3Nanyang Technological University, Singapore, Singapore
First Author:
Co-Author(s):
Introduction:
Affectionate touch is a fundamental aspect of the human experience from the very start of life. The sensory pathway for affectionate touch is anatomically segregated, primarily transmitted by unmyelinated, slow-conducting C-tactile (CT) afferents optimally activated by gentle stroking at 1-10 cm/s. In the neonatal period, skin-to-skin and stroking touch tune long-term somatosensory development, autonomic reactivity, social cognition, and bonding; however, neonatal neural processing of affectionate touch is not well understood. We aimed to examine neonatal brain activation in response to social/nonsocial and CT-targeted/non-CT-targeted touch stimuli and to interrogate the neural underpinnings of touch-mediated mother-infant interaction by recording simultaneous or "hyperscanning" maternal-newborn electroencephalography (EEG) at the neonatal cotside.
Methods:
Before recruitment, we piloted with 14 mother-newborn dyads and incorporated their perspectives to develop a participant-driven paradigm. Our refined paradigm compares neural activation across touch context and touch mechanism in a 2x3 factorial design with order counterbalanced (Figure 1). For touch context, mothers and infants are skin-to-skin ("social") or separate ("nonsocial"). For touch mechanism, the infant receives still touch ("static"), slow stroking (~1-10 cm/s, "CT-optimal"), or fast stroking (~20 cm/s, "non-CT-optimal") across the back. Touch conditions are of 3-minute duration with alternating 3-minute periods of baseline (no touch) before and after. Simultaneous maternal-newborn EEG is recorded at 500 Hz on LiveAmp wireless amplifiers with actiCAP electrodes (Brain Products). With EEGLAB, recordings are highpass filtered at 0.5 Hz and lowpass filtered at 40 Hz, and artefacts are manually rejected. Hand position information is monitored with open-source QR pose estimation markers (ArUco) and a synchronised high frame rate video camera. Stroking speed is calculated from ArUco position information with a custom algorithm.
·Figure 1. EEG hyperscanning paradigm at the neonatal cotside.
Results:
We applied EEG hyperscanning to study 43 mother-newborn dyads in the days after birth. Clean data from at least one touch condition was present in 30 healthy term-born newborns (11 female; mean 3409 grams, 39+4 weeks gestation, 1.7 days old) with their mothers (mean 32.0 years old). Stroking speed was calculated across stroking touch conditions. Average stroking speed was within 1-10 cm/s for all CT-optimal touch conditions and above this range for all non-CT-optimal touch conditions. We calculated neonatal broadband EEG power (μV²/Hz) across 1-10 Hz in frontal, central, and parietal regions, subtracting baseline (N = 30). We found significant differences in EEG power between social and nonsocial contexts for static and CT-optimal, but not non-CT-optimal, touch (Figure 2). Specifically, we found decreased neonatal broadband EEG power, representing increased neural activation, in the social context as compared to the nonsocial context for static touch and CT-optimal touch conditions.
·Figure 2. Neonatal EEG responses to touch conditions.
Conclusions:
We established and refined an EEG hyperscanning paradigm at the neonatal cotside across types of affectionate touch. Preliminary results indicate that static and CT-targeted touch stimuli elicit different neural activation responses in the newborn depending on the social context of the touch. Our findings are consistent with reports of decreased EEG power, or event-related desynchronization, during social as compared to nonsocial conditions in older infants. Additional recruitment and analyses of maternal-newborn neural synchronicity are currently underway. We hope our results will help elucidate the roles of social touch stimuli and the CT afferent pathway in early brain development as well as help characterise the beginnings of the mother-child inter-brain network.
Emotion, Motivation and Social Neuroscience:
Social Interaction
Lifespan Development:
Normal Brain Development: Fetus to Adolescence 2
Novel Imaging Acquisition Methods:
EEG
Perception, Attention and Motor Behavior:
Perception: Tactile/Somatosensory 1
Keywords:
Development
Electroencephaolography (EEG)
Experimental Design
NORMAL HUMAN
PEDIATRIC
Perception
Social Interactions
Somatosensory
Touch
1|2Indicates the priority used for review
Provide references using author date format
Löken, L. (2009), ‘Coding of pleasant touch by unmyelinated afferents in humans’, Nature Neuroscience, vol. 12, no. 5, pp. 547-548.
McGlone, F. (2014), ‘Discriminative and affective touch: sensing and feeling’, Neuron, vol. 82, no. 4, pp. 737-755.
St. John, A.M. (2016), ‘Variation in infant EEG power across social and nonsocial contexts’, Journal of Experimental Child Psychology, vol. 152, pp. 106-122.
Turk, E. (2022), ‘Brains in sync: practical guideline for parent-infant EEG during natural interaction’, Frontiers in Psychology, vol. 13, 833112.