Objective: The chronicity of the problem of conductive pathologies, the lack of improvement with treatment, and the progression of hearing loss are seen as important criteria for using hearing aids. In the event of delay in the intervention of conductive hearing losses, the lack of sound transmission may cause auditory deprivation. In conduction pathologies, word discrimination scores are maintained in quiet while performance decreases in the presence of noise. The aim of this study is to evaluate the effect of hearing aid use on speech discrimination in quiet and noise in conduction pathologies by using the Turkish matrix test as well as its effect on temporal processing.

Methods: Sixty-eight patients with mild to moderate conductive hearing loss participated: 23 patients were bilateral hearing aid users, 22 patients were unilateral users and 23 patients who did not use hearing aids. Thirty-one normal-hearing subjects were also included as a control group. Acoustic immitancemetry (tympanogram and acoustic reflexes) and pure-tone audiometry (air and bone conductions) were measured. The Turkish matrix test was performed at +5, 0 and -5 dB signal-to-noise ratio (SNR) with supra-aural headphone (TDH-39). In addition, the gaps in noise, duration pattern and frequency pattern tests were also performed to assess temporal processing.

Results: In the Matrix test performed at all SNRs, a significant difference was found between the scores of the conductive-loss group that did not use hearing aids and the groups that used bilateral or unilateral hearing aids. When the ears of the group with unilateral hearing aids were compared with and without the device, no significant difference was found between the test scores. In addition, temporal processing performance for those with long-term conductive hearing loss who had never used hearing aids was significantly worse than those that used one or two hearing aids.

Conclusion: These results indicate that although the cochlea and auditory nerve can be initially intact in conduction pathologies, the existing hearing loss may lead to auditory deprivation and the speech discrimination performance in noise may be affected. Early intervention with appropriate amplification in conductive pathologies may contribute to speech in noise performance as well as basic temporal processing.