Interaction between Speech Variations and Background Noise on Speech Intelligibility by Mandarin-Speaking Cochlear Implant Patients

In this study, the effect of varying speaking rates and styles and background noise on speech understanding was investigated in Mandarin-speaking CI and normal-hearing (NH) listeners. Thirteen (5 male and 8 female, age 19 to 62 years) Mandarin-speaking, post-lingually deafened adult CI patients using their clinical processors and 9 (5 male and 4 female, age 23 to 59 years) NH subjects listening to unprocessed speech. Five different types of speech variations, including 3 speaking rates (slow, normal, fast) and 2 speaking styles (emotional, shouted) were presented with two masking noises (speech-shaped steady state noise-SSN or six-talker babble). Speech reception threshold, defined as the signal-to-noise ratio producing 50% correct word-in-sentence recognition using Mandarin Speech Perception materials was measured. NH listeners performed significantly better (16.7dB) than CI patients across all conditions regardless of speech variations and noise types. CI patients’ performance deficit was highly dependent on speech rate and noise type; the deficit was smallest (11.7dB) when slowly-spoken speech was presented in SSN and largest (20.6dB) when shouted speech was presented in six-talker speech babble. NH listeners performed significantly better in speech babble than in SSN for all speech variations, while CI patients performed similarly in both noise types. The use of clear and slowly-spoken speech in the laboratory setting may largely underestimate CI patients’ performance...
Source: Speech Communication - Category: Speech-Language Pathology Source Type: research