Phonetic correlates of laryngeal and place contrasts of Burushaski

Abstract

Burushaski is an endangered language isolate spoken in Hunza, Nager, and Yasin valleys of Gilgit, Northern Pakistan. The present study investigates the acoustic correlates of Hunza Burushaski’s three-way stop laryngeal contrast (voiceless unaspirated, voiceless aspirated, and voiced unaspirated) across five places of articulation (bilabial, dental, retroflex, palatal, and velar). A wide range of acoustic correlates were measured, including Voice Onset Time (VOT), fundamental frequency (f0), first four formants (F1, F2, F3, and F4), spectral moments of stop release bursts (spectral center of gravity, spectral standard deviation, spectral skewness, and spectral kurtosis), and spectral tilt (H1*–H2*, H1*–A1*, H1*–A2*, and H1*–A3*). The data were collected from four Burushaski speakers. The findings indicated that voiceless aspirated consonants exhibited longer Voice Onset Time and higher spectral tilt onsets than their voiceless unaspirated and voiced unaspirated counterparts. The fundamental frequency was raised in both voiceless series. Some acoustic measures (e.g., Voice Onset Time and fundamental frequency) were better indicators of the laryngeal contrasts while others (spectral moments) more reliably distinguished the place contrasts. The results of Linear Discriminant Analysis (LDA) showed that a combination of spectral tilt and Voice Onset Time are the best descriptors of the three laryngeal categories of Burushaski.