When to Laugh, When to Cry: Display Rules of Nonverbal Vocalisations

Nonverbal vocalisations like laughter, sighs, and groans are a fundamental part of everyday communication. Yet surprisingly little is known about the social norms concerning which vocalisations are considered appropriate to express in which context (i.e., display rules). Here, in two pre-registered studies, we investigate how people evaluate the appropriateness of different nonverbal vocalisations across locations and relationships with listeners. Study 1, with a U.S. sample (n = 250), showed that certain vocalisations (e.g., laughter, sighs, cries) are consistently viewed as more socially acceptable than others (e.g., roars, groans, moans). Additionally, location (private vs. public) and interpersonal closeness (close vs. not close) significantly influenced these perceptions, with private locations and close relationships fostering greater expressive freedom. Study 2 extended this investigation into four cultural contexts (n = 1120 in total): the U.S. (for direct replication), Türkiye, China, and the Netherlands. Findings largely replicated those from Study 1 and supported the existence of cross-culturally consistent patterns in display rules for nonverbal vocalisations, though with some variation across cultures. This research expands our understanding of how social norms affect auditory communication, extending beyond the visual modality of facial expressions to encompass the rich world of nonverbal vocalisations.