Cross-linguistic vowel category formation: a comprehensive study of formant dynamics and intelligibility in Arabic and English vowel systems

This study explores vowel inherent spectral change and intelligibility across languages, focusing on differences between Arabic and English vowel systems. The aim of the research is to identify phonetic variation in cross-linguistic vowel acoustics that will provide the basis for Cross-Linguistic Vowel Category Formation. The paper scientific novelty is determined by obtaining new evidence that vowel category formation and intelligibility are shaped by language-specific weighting of either spectral change or duration. Static and dynamic formant properties were assessed to evaluate their contribution to the formation of vowel categories and resulting perceptual robustness across the two languages. Cross-language identification performance was significantly poorer (Arabic listeners on English vowels: 72%; English listeners on Arabic vowels: 70%), with errors characterized by static overlap and loss of dynamic contrast. Trajectory metrics were strong predictors of noise robustness, especially for English vowels. The results provide novel evidence for the expansion of frameworks accounting for cross-linguistic phonetic interaction by integrating dynamic formant cues into the Speech Learning Model (and Perceptual Assimilation Model) model framework.