Scientists from Yale provide evidence brainwaves in a specific brain region synchronize mother-child neural activity, which may direct future research on the social brain.
Written by Brett Weiss
An emergent understanding of how humans coordinate social interactions develops as neuroscience research moves beyond studying one brain’s function to two-brain communication. Studies assessing brainwave and behavioral synchronization-induced bonding between two individuals—dyads—provides insight into how affiliative members coordinate group responses. The mother-child dyad lays a crucial neurological template in our brains that facilitates the capacity to form such group affiliations and intimate relationships later in life.
Feldman and colleagues from Yale published a study in Social Cognitive and Affective Neuroscience where they identified an active brain region critical in mother-child bonding called the superior temporal sulcus. The researchers identified gamma brainwaves—a type of brain electrical impulse oscillation—correlated with short-term memory and attention that synchronize in the mother-child bond.
Interactions between mother and child that included laughs, giggles, and excitement were considered instances of behavioral synchronization. Comparing brain activity during behavioral synchronization to non-synchronous behavior—where neither mother nor child displayed positive interactions—allowed the scientists to parse out what regions activated during synchrony. The superior temporal sulcus area on the right side of the brain became activated during positive behavioral synchrony with prevalent gamma wave oscillations. Since social neuroscience models indicate the mother-child pairing in early life lays the neurological template for future group interactions, the results suggest subsequent research can examine brainwaves in this region.
Their analyses suggested the positive behavioral and communicative synchrony between the mother-child dyad induced brainwave synchrony rather than a shared psychological perspective doing so. In other words, rhythmic effects of communication and nonverbal behavior—sensory bottom-up neural processing—may have prompted the mother-child synchrony as opposed to thinking about the other’s perspective. Superior temporal sulcus gamma brainwave synchronization occurred exclusively during behavioral synchrony and not non-synchronous periods, implying no concretely shared psychological perspective between child and mother.
“To our knowledge this is the first study to use the mother-child context to assess neural coordination by utilizing individually tailored stimuli collected in the natural habitat, focus on brain rhythms and anchor neural coupling in moments of behavioral synchrony,” stated Feldman and colleagues in their publication. “We further found that neural coupling in both partners’ brain rode on fast, bottom-up gamma-band rhythms and was anchored in second-by-second coordination of non-verbal social signals.”
“Gamma oscillations are bottom-up-directed, and [superior temporal sulcus] is a key node in bottom-up processing of social processing,” added the scientists in their article. At the same time, the superior temporal sulcus integrates the use of general knowledge to interpret sensory perceptions—top-down processing. Researchers assume gamma oscillations are top-down controlled, so in this way, split-second events in mother-infant synchrony integrate into higher-order verbal dialogue, perspective taking, and conflict negotiation in later childhood. Mother-child brain synchronizations integrate bottom-up sensory information with top-down interpretations to create future synchronizing behavioral coordination with social partners.
“Consistent with the notion that the parent-infant bond provides the neurobiological template for pair bonding in both humans and animals, our findings indicate the neural signature detected in the context of the mother-child bond translates into other meaningful relationships throughout life.” The study’s findings can contribute to research on the brain basis of human social life, potentially pointing to superior temporal sulcus gamma waves to guide studies of the social brain. Following this direction may enrich human social brain research.
Levy J, Goldstein A, Feldman R. Perception of social synchrony induces mother-child gamma coupling in the social brain. Soc Cogn Affect Neurosci. 2017 Jul 1;12(7):1036-1046. doi: 10.1093/scan/nsx032. PMID: 28402479; PMCID: PMC5490671.