The subtle cue that can reveal whether someone is a narcissist

In Greek mythology, Narcissus is a vain young man who falls in love with his own reflection. Clinically speaking, narcissistic personality disorder is the figurative equivalent of that famous story: A narcissist places themselves on a high pedestal and engages in toxic behavior as a result. Hence, narcissists are typically chronically stubborn, entitled and envious, and/or oversensitive to criticism.

Most people want to avoid narcissists, whether in their work lives or in their personal lives; dating a narcissist, for example, means you will always be in love with a person who views others mainly as extensions of themselves. (That can have all kinds of deleterious mental health effects, and there is an entire cottage industry in publishing dedicated to recovering from a narcissistic partner.)

The challenge lies in the fact that saying you'll avoid narcissists is easier than actually detecting them. That's because narcissists are typically either oblivious or not forthcoming regarding their disposition.

Fortunately for anyone who is keen to avoid introducing a narcissist into their life, a recent study in the scientific journal Psychophysiology found that there's a secret "tell." Narcissists, psychologists say, hate being criticized; and it turns out that narcissists are prone to subtly disclosing their unusually acute discomfort that accompanies criticism.

Apparently it all comes down to their facial muscles.

"The results of our study show that people with narcissistic traits exhibit pronounced covert emotional reactivity to negative feedback regarding their performance," explained Dr. Ville J. Harjunen — a postdoctoral researcher of psychology and logopedics at the University of Helsinki, as well as the study's corresponding author — in an email to Salon.

"Covert emotional reactivity" means that, although the narcissist may not intentionally display their emotions, they nevertheless reveal in inadvertent and subtle ways that they are having an emotional reaction to criticism. 

"By measuring the electrical activity of the individuals' facial muscles, we were able to reveal that grandiose narcissism is associated with facial muscle activity related to anger and frustration when receiving self-threatening feedback even though they did not report being emotionally shaken by the feedback," Harjunen told Salon.

To learn this, the researchers found 57 individuals between the ages of 18 and 44, determined the extent to which they had narcissistic tendencies and then had them perform a pair of challenging cognitive tests. After they were finished, the participants were connected to machinery that monitored their biological responses while they were offered feedback — some of it neutral, some of it negative. Even though the more narcissistic individuals self-reported that they did not feel particularly upset by the negative feedback, they were much more likely than the less narcissistic participants to experience amplified activity in terms of eye constriction and frowning. That suggests the criticism appeared to upset them much more, and though they may not have admitted it, it was revealed in their physiological changes.

In addition, even the narcissistic participants could not deny that they felt somewhat diminished in terms of their sense of dominance and positive affect.

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"Individuals with higher levels of grandiose narcissism may not be willing to report overt emotional reactivity to self-threatening feedback, but physiological responses 'beneath their thin skin' reveal amplified threat-related facial muscle activity suggestive of a negative emotional state," the study's authors concluded.

While it may be tempting to use these findings to try to "prove" that a suspected or confirmed narcissist in your life knows they are wrong and is simply being stubborn, the researchers urge caution.

"Identifying narcissistic tendencies in people based on single encounters is very hard or even impossible," Harjunen wrote to Salon. "The results here are based on a controlled experiment with a sample of 57 individuals who were monitored in different feedback situations. So, detecting narcissism-related cues in a person's expressions or ways of interacting requires a lot of data gathered in a systematic manner."

At the same time, this does not mean that ordinary people are hopeless when trying to identify narcissists. They just need to use tried-and-true methods.

"Grandiose narcissism has been linked to seeking admiration, manipulativeness, and proneness to hostility when being criticized," Harjunen observed. "These behaviors and emotional tendencies occur in non-narcissistic individuals as well but to a lesser extent. Our study shows that grandiose narcissism increases emotional reactivity to self-threatening feedback. The reactions can, however, remain covert since these individuals seem to be very good at regulating their overt emotional reactions at least in contexts where they are monitored."

Going forward, the authors hope to study "whether the vigilance shows also in informal interactions with friends or colleagues and whether there is a certain threshold after the covert emotional burden turns into overt hostility."

The authors of the Psychophysiology paper are not the only experts to distinguish between normal human resistance to criticism and the behavior of narcissists. It is the difference between situational stubbornness, in which people are passionately invested in a certain opinion to a perhaps irrational degree, and the pathological stubbornness of those who never admit they are wrong because they wish to dominate others.

"You make the correct distinction between 'normal human stubbornness' and recalcitrance to an 'excessive degree' — or at least what psychiatrists such as myself concern themselves with, since distinguishing between health and disease is important," explained psychiatrist Dr. Bandy X. Lee in an email interview with Salon last month. "This is because healthy personality features will be life-affirming, no matter their direction in the marvelous tapestry of human diversity and resilience."

She added that when people refuse to admit they are wrong to a degree where it is downright maladaptive, "it can be defined as pathology."