Noise-induced differences in the complexity of spoken language.

Although speaking in noisy environments is a common occurrence, few studies have investigated how noise affects language production beyond the acoustic level. In seeking to differentiate between speaker- and listener-oriented modifications, this study examines the effect of noise on the complexity of language production and examines whether cognitive control predicts noise-induced modifications. Participants completed a picture description task via videoconferencing software while both the speaker (the participant) and listener (the experimenter) were exposed to multi-talker babble. Speakers produced fewer T-units, clauses, and words as well as fewer, but longer, unfilled pauses in noise. The degree of reduction in number of clauses, words, and unfilled pauses was significantly associated with weaker cognitive control. Thus, we consider these modifications to be speaker-oriented, driven by the distracting nature of noise. However, participants also produced fewer filled pauses and mazes in noise. These modifications were not significantly correlated with cognitive control, and they diverge from prior work demonstrating that speakers tend to produce disfluencies when they alone shoulder the burden of a noisy environment. This pattern of results suggests that speakers may alter their speech to alleviate cognitive burden on themselves as well as to facilitate comprehension for their listener.