The effect of cognitive load on temporal and disfluency patterns of speech

Abstract

Abstract This paper investigates how variation in the complexity of speech tasks is reflected in the temporal characteristics and disfluency patterns of speech. We examined temporal characteristics (speech rate, global articulation rate, ratio of pauses, frequency of pauses, and mean duration of pauses) and disfluency markers (overall frequency of disfluencies; frequency of filled pauses, filler words, whole-word repetitions, part-word repetitions, broken words, prolonged sounds, and revisions; frequency of disfluency clusters) in four speech production tasks (consecutive interpreting, sight translation, spontaneous speech and extemporaneous speech) with twelve speakers. Our hypothesis, according to which the examined parameters will differ across the four tasks, was partly confirmed by the data; even though not all speech tasks differed significantly in all the examined parameters, our investigation revealed that there were significant differences between some tasks in four parameters, and between others in nine out of the fourteen parameters examined. Our data also suggest that in terms of the temporal characteristics and disfluency markers examined, the four tasks can be represented on a continuum based on the cognitive load associated with each task. At one end of the continuum and generating the least cognitive load is spontaneous speech, and at the other, generating the most cognitive load, is sight translation.