Live interaction distinctively shapes social gaze dynamics in rhesus macaques

Abstract

The dynamic interaction of gaze between individuals is a hallmark of social cognition. However, very few studies have examined social gaze dynamics after mutual eye contact during real-time interactions. We used a highly quantifiable paradigm to assess social gaze dynamics between pairs of monkeys and modeled these dynamics using an exponential decay function to investigate sustained attention after mutual eye contact. When monkeys were interacting with real partners compared with static images and movies of the same monkeys, we found a significant increase in the proportion of fixations to the eyes and a smaller dispersion of fixations around the eyes, indicating enhanced focal attention to the eye region. Notably, dominance and familiarity between the interacting pairs induced separable components of gaze dynamics that were unique to live interactions. Gaze dynamics of dominant monkeys after mutual eye contact were associated with a greater number of fixations to the eyes, whereas those of familiar pairs were associated with a faster rate of decrease in this eye-directed attention. Our findings endorse the notion that certain key aspects of social cognition are only captured during interactive social contexts and dependent on the elapsed time relative to socially meaningful events.

Oxytocin under opioid antagonism leads to supralinear enhancement of social attention

“…For testing the behavioral impact of combined delivery of OT and NAL, pairs of monkeys sat directly across from each other while the eye positions from both monkeys were simultaneously and continuously recorded (32) (Fig. S1 A and B).…”

“…Before starting to record gaze behavior, each animal underwent a systematic calibration procedure (details are provided in SI Materials and Methods, Behavioral Tasks and ref. 32). During the calibration and until the beginning of each session, the two animals had no visual access to each other, with a screen fully separating the view of both animals.…”

New perspectives on the neurophysiology of primate amygdala emerging from the study of naturalistic social behaviors

“…Most importantly, these results pave the way for future experiments that will replace videos with live interactions with conspecifics as already pioneered by a few laboratories. 70,78,81,82 The ideal development would be to implement in the laboratory closed-loop social interactions. The social brain evolved to process social signals and make social decisions in closed-loop interactions—and neural activity monitored under such conditions holds the promise of further exciting discoveries.…”

Social determinants of eyeblinks in adult male macaques

“…Indeed, the two monkeys that showed eyeblink entrainment also looked longer at the eyes of the stimulus monkeys, reciprocating more often their direct gaze. Looking insistently at the eyes and returning eye contact are indicative of dominant social status in macaque societies30. The failure of the viewer monkeys to reciprocate the blinks of their social partner might therefore represent an active form of avoiding social engagement with a dominant individual.…”