The effect of extroversion on communication: Evidence from an interlocutor visibility manipulation

• We compare people’s speech and gesture use when they can and cannot see their listener.
• We measure how extroverted-introverted speakers are.
• We find that people speak and more when they cannot see their listener.
• Extroversion affects how much speakers gesture but not how much they speak.
• These results suggest that extroversion affects how people interpret the nonverbal cues of their interlocutor.

In this study we test how introversion–extroversion affects language and gesture use depending on whether the interlocutor is visible to the speaker. Adults described arrays of objects, half the time with a screen occluding their interlocutor and half the time with the interlocutor visible. When participants could not see their listener, they used more words, particularly concrete words and tended to gesture more. This difference was moderated by extroversion for gestures (i.e., extroverts gestured more when their interlocutor was occluded) but not for speech. We argue that visibility of a listener may influence how speakers use nonverbal feedback from their interlocutors differentially according to extroversion. In particular, visibility and personality may impact how speakers use gestures when they do not know whether their interlocutor has understood them.