Smile (but only deliberately) though your heart is aching: Loneliness is associated with impaired spontaneous smile mimicry

ABSTRACT

As social beings, humans harbor an evolved capacity for loneliness – perceived social isolation. Loneliness is associated with atypical affective and social processing, as well as physiological dysregulation. We investigated how loneliness influences spontaneous facial mimicry (SFM), an interpersonal response involved in social connection and emotional contagion. We presented participants with emotional stimuli, such as video clips of actors expressing anger, fear, sadness, or joy, and emotional IAPS images. We measured participants’ zygomaticus major (“smiling”) muscle and their corrugator supercilii (“frowning”) muscle with facial electromyography (fEMG). We also measured self-reported loneliness, depression, and extraversion levels. For socially connected individuals we found intact SFM, as reflected in greater fEMG activity of the zygomaticus and corrugator to positive and negative expressions, respectively. However, individuals reporting higher levels of loneliness lacked SFM for expressions of joy. Loneliness did not impair deliberate mimicry activity to the same expressions, or spontaneous reactions to positive, negative, or neutral IAPS images. Depression and extraversion did not predict any differences in fEMG responses. We suggest that impairments in spontaneous “smiling back” at another – a decreased interpersonal resonance – could contribute to negative social and emotional consequences of loneliness and may facilitate loneliness contagion.

KEYWORDS:

• Loneliness
• facial mimicry
• mimicry
• electromyography (EMG)
• fEMG
• smile(s)
• social isolation
• isolation
• social connection

Author contributions

AJA developed the original idea of exploring how loneliness affects mimicry. Both authors contributed equally to the study design. Testing, data collection, and data analysis were performed by AJA under the supervision of PW. AJA drafted the manuscript and PW provided critical revisions. All authors approved the final version of the manuscript. Correspondence may be addressed to [email protected] or to [email protected].

Data are posted at OSF: https://osf.io/wv7gu/?view_only=c289e618970943f4876afc08c3472c7d

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by the Academic Senate, University of California, San Diego [059455].