EFFECT OF SENSORINEURAL HEARING LOSS ON THE TIME-COMPRESSED SPEECH TEST

Abstract

Background: The comprehension of spoken language is based on the analysis of complex acoustic signals by the cen- tral auditory system. Cognitive declines and deficits in speech understanding are seen in aged individuals and also in the hearing impaired. The Time-Compressed Speech Test is a low redundancy central auditory processing test that evaluates the closure ability to recognise degraded acoustic speech, words, or sentences. Material and Methods: In this work, we evaluated the difficulties in understanding compressed speech. Volunteer pa- tients, both with normal hearing and with hearing loss, took part in the experiments. Also a group of hearing aid users were included. The stimuli consisted of speech words that were either unmodified in duration or time-compressed and presented at the most comfortable level. Results: An inverse relationship was seen between the compression ratio and the capacity to identify correctly the words presented. Compressed words were worse perceived by hearing-aid users than by patients with flat audiograms and with a high-frequency hearing loss. Conclusions: In patients with a flat audiogram, a deficit in the mechanism of temporal resolution exists. Furthermore, hear- ing aids facilitate the audibility of sound even though they do not act efficiently with speech at high ratios of presentation. Background