People with psychopathic personality traits, such as remorselessness, are less likely to yawn after seeing another person yawn, according to new research published in Scientific Reports.
Contagious yawning is well-documented in humans, and previous research has provided evidence that there is a positive link between empathy and the susceptibility to contagious yawning. Psychopathy is characterized by callous and domineering behavior as well as deficits in empathy, which might cause those with psychopathic traits to be less susceptible to contagious yawning.
“In recent years, there has been growing interest in understanding the factors that contribute to variation in yawn contagion. However, previous psychological studies examining individual differences in the contagiousness of yawning have produced mixed results,” said study author Andrew C. Gallup, an associate professor of Psychology at the State University of New York Polytechnic Institute.
“In addition, many of these studies have been conducted on relatively small and homogenous samples. Recruiting the largest and most diverse sample in the study of contagious yawning to date, the current research aimed to replicate and extend upon previous research suggesting a negative relationship between contagious yawning and psychopathic personality traits.”
In the new study, 458 participants from 50 different countries watched a 3-minute video depicting 49 yawns from humans and 1 yawn from a dog. They were then asked to indicate whether they had yawned while watching the video. Afterward, the participants completed multiple assessments of psychopathic traits.
Approximately 63% of the participants reported yawning contagiously in response to the video. The researchers found that individuals who reported yawning tended to score lower on the psychopathy assessments compared to those who did not yawn.
“People who score higher on psychopathic personality traits tend to be less likely to yawn contagiously,” Gallup told PsyPost. “These findings support previous research suggesting that psychopathy is associated with a generalized impairment in behavioral contagion and biobehavioral synchrony. In addition, our results show that, similar to spontaneous yawning, yawn contagion is enhanced by participant fatigue/tiredness.”
The findings held even after the researchers controlled for gender, age, prior sleep the previous night, self-reported tiredness, and objective and subjective levels of attention to the video. But the study, like all research, includes some caveats. “This study was conducted online, and the reliance on self-reported data and the inability to monitor participant attention towards the contagious yawning stimulus were the biggest limitations,” Gallup said.
The new results, however, are in line with a previous study, which used facial electromyography and galvanic skin response as objective measures of yawn contagion.
But the researchers noted that the strongest predictor of contagious yawning was actually self-reported tiredness. “Thus, we should not immediately write somebody of as a psychopath when he or she does not yawn in response to seeing someone else yawn,” remarked co-author Jorg J. M. Massen in a news release. “He or she might just not be tired enough.”
The new study, “People that score high on psychopathic traits are less likely to yawn contagiously“, was authored by Andrew C. Gallup, Mariska E. Kret, Omar Tonsi Eldakar, Julia Folz, and Jorg J. M. Massen.