Speech Rhythm in Individuals with Stuttering

Abstract

The objective of this study was to investigate speech rhythm in persons who stutter. Ten adults who stutter and ten age and gender matched controls participated in the study. Participants in both the groups were native speakers of Kannada. Five sentences were constructed in Kannada and the participants were asked to read out these sentences. Using Praat software, two kinds of rhythm metrics were calculated- pairwise variability indices and interval measures. Pairwise variability indices include normalized Pairwise Variability Index for vocalic intervals (nPVI - V) and raw Pairwise Variability Index for consonantal intervals (rPVI - C). Interval measures include percentage of vocalic intervals, standard deviation of the vocalic and consonantal intervals, and coefficient of variables for vocalic and consonantal intervals. Significant difference (p < 0.05) between the two groups was present for all the interval measures except coefficient of variables for vocalic intervals. However, there was no significant difference (p > 0.05) between the groups for Pairwise variability measures (nPVI - V and rPVI - C). The durational differences between the successive stressed and unstressed segments are taken into consideration in pairwise variability indices. The findings of the present study indicate that few measures of speech rhythm are deviant in persons who stutter while the others indicate that they follow the same rhythm pattern.