Oxytocin enhances inter-brain synchrony during social coordination in male adults

Abstract

Recent brain imaging research has revealed oxytocin (OT) effects on an individual's brain activity during social interaction but tells little about whether and how OT modulates the coherence of inter-brain activity related to two individuals' coordination behavior. We developed a new real-time coordination game that required two individuals of a dyad to synchronize with a partner (coordination task) or with a computer (control task) by counting in mind rhythmically. Electroencephalography (EEG) was recorded simultaneously from a dyad to examine OT effects on inter-brain synchrony of neural activity during interpersonal coordination. Experiment 1 found that dyads showed smaller interpersonal time lags of counting and greater inter-brain synchrony of alpha-band neural oscillations during the coordination (vs control) task and these effects were reliably observed in female but not male dyads. Moreover, the increased alpha-band inter-brain synchrony predicted better interpersonal behavioral synchrony across all participants. Experiment 2, using a double blind, placebo-controlled between-subjects design, revealed that intranasal OT vs placebo administration in male dyads improved interpersonal behavioral synchrony in both the coordination and control tasks but specifically enhanced alpha-band inter-brain neural oscillations during the coordination task. Our findings provide first evidence that OT enhances inter-brain synchrony in male adults to facilitate social coordination.

On the Same Wavelength: Exploring Team Neurosynchrony in Undergraduate Dyads Solving a Cyberlearning Problem With Collaborative Scripts

“…A subsample of 80 participants (40 dyads) took part in the team neurosynchrony portion of the study. Prior EEG hyperscanning studies have employed anywhere from 12 participants (Dikker et al, in a group neurosynchrony study) to 68 participants (Mu et al, in a dyadic neurosynchrony study). Neurosynchrony study participants were all right‐handed, and reported no history of brain trauma and current prescriptions for medications that affect mental activity.…”

“…Team neurosynchrony was assessed by calculating phase synchrony of continuous alpha‐band activity in the participants' EEG using PLV, an established measure of across‐brain neurosynchrony (Dumas et al, ; Linkenkaer‐Hansen, Nikouline, Palva, & Ilmoniemi, ; Mu et al, ). First, we identified time windows when both participants in each dyad were silent between conversations and computer usage.…”

“…In previously published research using PLV as a measure of across‐brain synchrony and Morlet wavelets as a time frequency representation of the signal (e.g., Mu et al, ), 10 trials were completed by 17 dyads in each experimental condition, producing good signal‐to‐noise ratios. After the segmentation and artifact removal, PLVs were quantified based on a wavelet decomposition of the alpha signal (between 8 and 13 Hz) in 1 Hz steps, similar to prior studies (Linkenkaer‐Hansen et al, ; Mu et al, ; Mu, Fan, Mao, & Han, ; Mu & Han, , ). The signal was then convoluted by the complex Morlet wavelet w ( t, f 0 ) with a Gaussian shape in time ( SD σ t ) and frequency ( SD σ f ) domains around its central frequency f 0 with σ f = 1/2 πσ t , as depicted in Figure .…”

“…Using complexity science as the framework, Stevens and Galloway () defined teams as self‐organized flows of information that consolidate periodically around a common goal and change form as the task and environment evolve. As teammates adjust their cognition and behavior, their information exchanges synchronize across different systems including gestural (Ashenfelter, ), postural (Shockley, Santana, & Fowler, ), verbal (Drew, ), physiological (Guastello, Pincus, & Gunderson, ), and, more recently, neurophysiological (Mu, Guo, & Han, ; Poulsen, Kamronn, Dmochowski, Parra, & Hansen, ; Stevens & Galloway, ).…”

“…Mu et al () employed a hyperscanning dual‐EEG setup and PLV to explore dyadic neurosynchrony during a coordination game in which two participants were asked to synchronize with a partner (coordination task) or with a computer (control task) by counting in mind rhythmically in order to make a button press at the same time after counting. Greater across‐brain synchrony of alpha‐band neural oscillations was observed during the coordination (vs. control) task in female but not male dyads.…”