Quinine causes a temporary disruption of outer hair cell (OHC) function, and thus can be used to examine the role of OHCs on auditory perception. In the present study, frequency selectivity, temporal resolution, and speech recognition were measured before, during, and after a quinine‐induced hearing loss. Normal‐hearing listeners ingested 5.76–11.43 mg/kg body weight of quinine, resulting in 5–15 dB of hearing loss. Frequency selectivity was estimated by comparing the level of a noise masker needed to mask a fixed‐level, 2‐kHz signal when the masker contained a spectral gap at 2 kHz and when it contained no gap. Similarly, temporal resolution was estimated by comparing the masker level needed to mask the 2‐kHz signal when the noise masker contained a temporal gap and when it did not. Speech recognition thresholds were measured in quiet and in the presence of a masker (speech‐shaped noise or time‐reversed speech) fixed at 70‐dB SPL. Signal level was varied adaptively to estimate 50% correct recognition. Quinine resulted in reduced frequency selectivity and reduced temporal resolution. Quinine also elevated speech recognition thresholds in quiet (by 7 dB on average), but the thresholds in the presence of the maskers were unaffected. [Work supported by NIDCD and AAA.]