The eye contact smile: The effects of sending and receiving a direct gaze

Eye contact often elicits a smiling response. We investigated whether an individual's awareness that the recipient perceives their direct gaze during eye contact has an influence on this smiling response. Participants wore glasses with either clear or dark lenses (preventing the other person from seeing their eyes). Measurements of electromyographic activity from the zygomatic and periocular muscle regions showed that the smiling responses were greater to seeing the other's direct versus averted gaze. The participants' own gaze direction had also an effect, and this effect was modified by the visibility of their eyes. Zygomatic responses were greater when the participants were aware that their eyes were visible. Thus, awareness of sending a direct gaze to another plays a role in the smiling response. In addition, participants' self-evaluated level of social anxiety was positively correlated with the magnitude of the zygomatic responses to the other person's direct versus averted gaze.