Some actions are contagious among humans — the instant you see someone do it, you feel the need to do it yourself. They’re called echo phenomena, and (pardon the cheesy early-90s greeting card jingo) there’s nothing so contagious as the human smile. Unfortunately, feeling lonely might make it difficult for us to ‘catch’ others’ smiles and happy facial expressions.
Researchers from the University of California, San Diego, say this impairment might be contributing to the much-reported loneliness epidemic.
The study involved 35 students who took tests to determine their personality and levels of depression and loneliness. They then each watched video clips of men and women making facial expressions of joy, anger, sadness, and fear. At the same time, students wore facial sensors to detect even the slightest movement in the muscles devoted to expression.
Both students identified as lonely and not lonely had no trouble instinctively responding to videos of anger, fear, and sadness with what is known as spontaneous facial mimicry — an involuntary empathetic phenomenon in which an animal reflects another’s facial expression.
But in response to the video expressions of joy, only non-lonely students smiled. Personality traits and depression scores appeared to have no effect; loneliness was the only difference between the people who spontaneously smiled in response to a joyful expression and those who did not.
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In follow-up tests, the researchers determined the lonely group did have the physical ability to spontaneously mimic a smile, they just didn’t do it as expected. The lonely group also spontaneously smiled in response to positive images that did not contain humans (like nature scenes); only human expressions of joy elicited no echo.
Researchers aren’t entirely sure what to make of their findings. It was a tiny study and would need much larger and repeated follow-up experiments to confirm this relationship between feelings of loneliness and spontaneous smiling. The research team posits that lonely people respond less to others’ smiles, and in doing so, send a distancing vibe that helps create or at least further their isolation — but it’s only a theory at this point. “Given the serious problem of loneliness in society and its danger to health, more research on how it presents in everyday social interactions is useful for greater understanding of and treatment of the condition, ourselves and each other,” the study concluded.
