Department of Physiology, College of Medicine, The University of Arizona, Tucson, AZ, 85724, USA.
Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, USA.
Sci Rep. 2016 Dec 6;6:38686. doi: 10.1038/srep38686.
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.
富含社会和情感内容的视频会引起灵长类动物的自然社交行为。事实上，猴子在观看同类的视频时，会进行眼神接触、目光跟随，并回应面部表情。我们假设眨眼的频率和时间也取决于视频中包含的社交信号。我们监测了四只成年雄性猕猴在观看同类表现出直接或回避目光的面部表情时的眨眼情况。四只动物的即时眨眼率在观看视频时都降低了。然而，眨眼的时间同步性在回应针对观看者的安抚或攻击面部表情的片段时增加了。在这四只猴子中，有两只猴子会系统地回应刺激猴子的直接注视，它们还表现出眨眼同步，这是在进行二元互动的社交伙伴之间的眨眼时间协调。总之，我们的结果表明，在猕猴中，与人类一样，眨眼不仅取决于保护眼睛和在角膜上散布泪膜的生理需要，还取决于几个社会情感因素。
