Unveiling the Unheard: Acoustic vs. Perceptual Insights into the Occurrence of Intrusive Vowels in Initial Consonant Clusters of Algerian Arabic

The phonetic nature of consonant clusters is much more intricate than what a human ear may perceive. In this scope, the present research paper aims to experimentally examine biconsonantal complex onsets in Algerian Arabic to unveil the presence of subtle vocalic intervals within these clusters. To this end, both acoustic and perceptual experiments were conducted to investigate the distribution and phonetic properties of intrusive vowels. Results revealed that certain onset clusters exhibited brief, elusive vocoids that do not stem from an epenthesis process but rather serve as transitional elements to coordinate consonantal gestures. These intrusive vowels were observed to surface only in the acoustic record while maintaining audibly intact clusters. Notably, their distribution was constrained by speech rate, degree of voicing, and the sonority profile of the juxtaposed consonants. Besides, they were found to possess a phonetic quality distinct from that of the adjacent lexical vowels.