Vocalic and intervocalic intervals in the speech of educated Idoma speakers of English

Abstract

The measurement of vocalic and intervocalic intervals, which has been proposed as a more reliable acoustic correlate of rhythm than inter-stress intervals or syllable duration, is usually not included in the description of the rhythm of Nigerian English, and little is known about how this contributes to the impression of rhythm in the speech of educated Idoma speakers of English. This study therefore investigated the speech rhythm of educated Idoma speakers of English by measuring vocalic and intervocalic intervals as acoustic correlates of speech rhythm. A carefully selected passage, read by 50 educated Idoma speakers of English, was analysed acoustically and statistically. The normalised pairwise variability index (nPVI) was employed to account for vocalic and intervocalic intervals in the speech of the participants in order show how this contributes to the impression of rhythm in their speech. The study indicated that there was no durational variability between successive vowels, in addition to low variability index values for vocalic and intervocalic intervals. These results showed syllable-timing rhythm. However, patterns from female participants along the continuum were less syllable timed than the male participants. There were also indications of sentence type variations with compound sentences, in some cases, less syllable timed than simple sentences.