Psychoacoustic forward masking Gaussian–Noise disruption measured across a range of hearing levels

Abstract

Recent work suggests that listeners with both normal hearing (NH) and sensorineural hearing loss (SNHL) exhibit more forward masking for a highly fluctuating Gaussian noise (GN) masker relative to a low-fluctuation noise (LFN) masker. This difference in masked thresholds, referred to as GN disruption, is affected by small differences in hearing sensitivity when measured using a brief (10-ms) probe signal and relatively short delays between masker offset and signal onset. We hypothesize that cochlear-gain control mediated by the medial olivocochlear (MOC) efferent system contributes to GN disruption. The current study used a behavioral forward-masking paradigm to measure GN disruption in human participants with hearing sensitivity ranging from normal to moderate SNHL. Results from one masker presentation level (80 dB SPL), two masker-signal delays (25 and 75 ms), and two masker types (GN and LFN) centered at 2000 Hz will be presented. This study is part of a series of experiments using physiological and otoacoustic-emission measures to assess GN disruption and the role of the MOC. Completion of these studies will improve our understanding of the mechanisms that contribute to excessive GN disruption in listeners with a range of hearing-sensitivity profiles.