Do Face Masks Inhibit Yawning? An Important Consideration in Sleep Studies

The COVID-19 pandemic has led to the widespread use of face masks to reduce disease transmission, but one unintended consequence is that this may negatively impact sleep and arousal by altering the expression of yawning. Yawns are defined by an involuntary and powerful gaping of the jaw with inspiration, and the typical design of face masks may restrict and/or disrupt the mandibular jaw movement and counter-current heat exchange during this behavior. Face masks additionally impair the contagious nature of yawning by disrupting the recognition of yawning in others within social/community settings. Given that the neurophysiological consequences of yawning function in facilitating changes in state and arousal, and most notably transitions in waking and sleeping via thermoregulation, face mask usage could be an important variable to consider within sleep studies. We briefly outline these connections, highlight some important factors to consider, and discuss the implications for both prior and current research on sleep.