The effects of noise on speech movements in young, middle-aged, and older adults

Abstract

People often talk in noisy environments, which can influence the effectiveness of communication. This study examined the impact of several types of noise on speech production by measuring lip movements during a sentence repetition task. Sixty participants in three age groups ranging from 20 to 70 repeated a sentence under five noise conditions (silence, one person reading aloud, two readers, six readers, and pink noise). A head-mounted strain gauge system tracked vertical lip movements. With the presentation of noise during a speaking task, the intensity increased due to the Lombard effect in all of the noise conditions. The utterance duration for the 1-talker condition was significantly shorter when compared to the silent condition. The peak velocity of a selected lip-closing gesture increased in all of the noise conditions compared to silence. Speech movement variability in the pink noise and 6-talker conditions was lower than in the silent condition. The repetitive nature of the sentence repetition task may not have required a high level of self-monitoring, resulting in speech output that was more automatic in the noise conditions. Speech movement differences as a function of the type of noise suggest that hearing speech while talking may be more distracting than speaking in the presence of continuous (e.g., pink) noise. Because people communicate in noisy environments every day, an increased understanding of the effects of noise on speech may have value from both theoretical and clinical perspectives.