title: Social determinants of eyeblinks in adult male macaques.
abstract: Videos with rich social and emotional content elicit natural social behaviors in primates. Indeed, while watching videos of conspecifics, monkeys engage in eye contact, gaze follow, and reciprocate facial expressions. We hypothesized that the frequency and timing of eyeblinks also depends on the social signals contained in videos. We monitored the eyeblinks of four male adult macaques while they watched videos of conspecifics displaying facial expressions with direct or averted gaze. The instantaneous blink rate of all four animals decreased during videos. The temporal synchrony of blinking, however, increased in response to segments depicting appeasing or aggressive facial expressions directed at the viewer. Two of the four monkeys, who systematically reciprocated the direct gaze of the stimulus monkeys, also showed eyeblink entrainment, a temporal coordination of blinking between social partners engaged in dyadic interactions. Together, our results suggest that in macaques, as in humans, blinking depends not only on the physiological imperative to protect the eyes and spread a film of tears over the cornea, but also on several socio-emotional factors.
authors.affiliation: Department of Physiology, College of Medicine, The University of Arizona, Tucson, AZ, 85724, USA.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Ballesta
authors.affiliation: Department of Physiology, College of Medicine, The University of Arizona, Tucson, AZ, 85724, USA.
authors.forename: Clayton P
authors.initials: CP
authors.lastname: Mosher
authors.affiliation: Department of Physiology, College of Medicine, The University of Arizona, Tucson, AZ, 85724, USA.
authors.forename: Jeno
authors.initials: J
authors.lastname: Szep
authors.affiliation: Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Kate D
authors.initials: KD
authors.lastname: Fischl
authors.affiliation: Department of Physiology, College of Medicine, The University of Arizona, Tucson, AZ, 85724, USA.
authors.forename: Katalin M
authors.initials: KM
authors.lastname: Gothard
mesh_terms: D000367:Age Factors; D000818:Animals; D001522:Behavior, Animal; D001767:Blinking; D008253:Macaca mulatta; D008297:Male; D012737:Sex Factors; D012919:Social Behavior