Acoustic Correlates of Stress in Nepali Language

Abstract

Stress provides an acoustic cue to a syllable, word or a part of a sentence to convey different intents without changing the meaning. The acoustic correlates of stress comprises of increased fundamental frequency, intensity, duration and vowel quality. These acoustic measures vary according to the structure of the language. There are no reports on the acoustic correlates of stress in Nepali. Hence, the present study aims to investigate the acoustic correlates of stress in Nepali language. A total of 20 native speakers of Nepali language in the age range of 18 to 30 years participated in the study. Ten bi-syllabic words consisting of an adjective and a noun were chosen. The participants were asked to read the two word phrases with and without stress on the adjectives that were marked in italics. The variations in stressed and unstressed conditions were analyzed for the marked adjectives. The peak fundamental frequencies (Fo), peak intensity (dB), duration (msec) were extracted from the adjectives of the 10 phrases using PRAAT (Version 5.3.17) software. S-ratio was also computed for the acoustic measures of stress for both the stressed and unstressed conditions. Descriptive analysis revealed increase in the Means of peak fundamental frequency (Fo), peak intensity (Io) and duration (Do) and t-test revealed significant increase in Fo and Io in both conditions. However, Do revealed no statistical significance in stressed and unstressed conditions.