Attachment Reminders Trigger Widespread Synchrony across Multiple Brains.

Area of Science:

• Neuroscience
• Social Psychology
• Evolutionary Biology

Background:

• Infant stimuli activate adult brains, highlighting the evolutionary importance of primary attachment.
• Attachment reminders may induce cross-brain concordance and neural uniformity among observers.

Purpose of the Study:

• To investigate if attachment cues trigger cross-brain synchrony and neural uniformity in human mothers.
• To examine the role of social context in mother-infant interactions on neural synchrony.

Main Methods:

• fMRI imaging of mothers during oxytocin/placebo administration.
• Presentation of ecological videos depicting mother-infant interactions (alone vs. social).
• Theory-driven analysis of the parental caregiving network (PCN) and data-driven whole-brain analysis for cross-brain synchrony.

Main Results:

• Widespread cross-brain synchrony was observed in the PCN and across the neuroaxis.
• The social context significantly increased cross-brain concordance compared to the alone context.
• Real-time fluctuations in mother-infant social synchrony were mirrored by cross-brain concordance in the anterior cingulate cortex (ACC).

Conclusions:

• Social attachment stimuli evoke substantial interbrain concordance, suggesting a mechanism for social bonding.
• The mother-infant bond may unify individual experiences and bind individuals into social groups.
• Social synchrony in attachment cues enhances neural similarity, providing a template for social group consolidation.