Processing of speech in complex listening environments by individuals with obscure auditory dysfunction

Abstract

Obscure auditory dysfunction (OAD) is a disorder for which patients report excessive amounts of difficulty understanding speech in the presence of background noise, despite no obvious evidence of hearing loss. It has been hypothesized that OAD may be the result of mild cochlear dysfunction, central auditory processing deficits, and/or psychological disorders. We evaluated 10 persons with self-reported problems understanding speech in noisy environments and 10 controls. Both groups had normal-hearing sensitivity and excellent word recognition in quiet. The following tests were administered to each participant: DPOAE and ABR assessment, central auditory processing screening, personality inventory, and tests involving speech recognition in complex environments. The speech recognition measures were a subset of tests reported in Hawley et al. [J. Acoust. Soc. Am. 115, 833–843 (2004)] and were designed to probe binaural processing ability, as well as spectral and temporal processing of speech in complex environments. The OAD participants had poorer overall speech recognition ability than did the controls in both single- (1.5 dB, p=0.017) and two-competitor environments (0.9 dB, p>0.05). However, the reported problems in these OAD participants are not attributable to poor binaural processing. [Funding provided by NIDCD.]