Cue Integration and Speech Rate in Arabic Stop-Vowel Sequences: A Multi-Parametric Acoustic Analysis

Abstract

The present study investigates how the variation of speech rate affects the acoustic cues across stop-vowel sequences in Bisha dialect (BD), an Arabic dialect spoken in the southern region of Saudi Arabia. Applying an acoustic approach, the study examines segmental duration (closure and following vowel), fundamental frequency (f0 onset), and voice quality (H1-H2 onset) on target stops taken from a sample of thirty native speakers of BD. The acoustic measures are evaluated using linear mixed-effects and logistic regression models. Results demonstrate that fast rate leads to substantial temporal compression, including more shortening of the vowels relative to the stops. Fast speech shows lower F0 at the beginning of the vowel, and this was larger in male speakers. Preceding stop voicing affects voice quality, with breathier onsets arising from voiced than voiceless stops at fast speech rates. Sex is a main source of prediction, with male speakers being less likely to be acoustically classified under the fast rate condition. These observations imply that the speakers implement unified articulatory mechanism to serve different speech tempos in BD for communicative efficiency and phonetic contrast. Compensation for faster speech in this study is not limited to temporal reduction; speakers also make acoustic adjustments such as pitch lowering and phonation modifications.