This study reports the first experimental exploration of possible contagious yawning in monkeys. Twenty-two stumptail macaques (Macaca arctoides) were presented with video clips of either yawns or control mouth movements by conspecifics. At a group level, monkeys yawned significantly more often during and just after the yawn tape than the control tape. Supplementary analysis revealed that the y...

Fatigue could be detected or predicted by the dynamic facial expression event: yawn. Facial expression parameters are extracted from real time video containing faces and used as observations for the underlying Hidden Markov Model for recognizing the yawn event. Promising results from tests by many users and their evaluations are reported.

In humans, the distribution of yawn contagion is shaped by social closeness with strongly bonded pairs showing higher levels of contagion than weakly bonded pairs. This ethological finding led the authors to hypothesize that the phenomenon of yawn contagion may be the result of certain empathic abilities, although in their most basal form. Here, for the first time, we show the capacity of bonob...

Contagious yawning has been reported for humans, dogs and several non-human primate species, and associated with empathy in humans and other primates. Still, the function, development and underlying mechanisms of contagious yawning remain unclear. Humans and dogs show a developmental increase in susceptibility to yawn contagion, with children showing an increase around the age of four, when als...

Contagious yawning, the onset of a yawn triggered by seeing, hearing, reading, or thinking about another person yawn is a well-documented phenomenon. The mechanisms that drive contagious yawning are as yet unknown, but there is recent evidence of a link between contagious yawning and self-processing (S.M. Platek, S.R. Critton, T.E. Myers, G.G. Gallup Jr., Contagious yawning: the role of self-aw...

In all the species of nonhuman primates for which data on sex differences in the frequency of yawning are reported, males yawn much more than females (Bertrand 1969; Deputte 1978; Goy and Resko 1972; Hadidian 1980; HA and DeVore 1965; Redican 1975; Rinaldi 1985; Wolfheim and Rowell 1972). This différence has been related to sexual dimorphism in canine size: The larger size of male canines may m...

In humans, the susceptibility to yawn contagion has been theoretically and empirically related to our capacity for empathy. Because of its relevance to evolutionary biology, this phenomenon has been the focus of recent investigations in non-human species. In line with the empathic hypothesis, contagious yawning has been shown to correlate with the level of social attachment in several primate s...