Speech rate and rhythm in cerebellar dysarthria: an acoustic analysis of syllabic timing.

Auditory-perceptual studies reported inconsistent data with respect to syllabic timing in cerebellar dysarthria, i.e. both reduced and increased variability of syllable durations. The present study performed a comprehensive analysis of syllabic timing during sentence utterances in 14 subjects with a pure cerebellar syndrome (CA). First, the CA patients presented with reduced speech tempo in terms of syllable and utterance durations. Second, a tendency for intrautterance syllabic isochrony, being an aspect of the percept of 'scanning speech', characterized a subgroup of patients with cerebellar dysarthria. Third, increased interutterance durational variability was found in three out of the five syllables considered. Thus, both reduced intrautterance and increased interutterance variability of syllable durations may pertain to cerebellar dysarthria. The latter dimension, however, seems to be more prominent.