The effects of lexical tone contour on Mandarin sentence intelligibility among adult hearing aid users

Abstract

This study investigated the effect of lexical tone contour on the speech intelligibility of Mandarin sentences among hearing aid users in quiet and in noise. Stimuli were synthesized Mandarin sentences with each word carrying the original lexical tone, flattened tone, or randomized tone selected from the four Mandarin lexical tones. Thirty-two people with moderate to severe sensorineural hearing loss participated and they wore hearing aids binaurally during the experiment. Significant declines in speech intelligibility were found in manipulated tone conditions no matter in quiet or in noise. Our results were consistent with previous findings to some extent and further suggested the importance of lexical tone contour hearing aid users, and that the effect of distorted lexical tone contour may not be compensable by other cues.