title: Inherent envelope fluctuations in forward maskers: Effects of masker-probe delay for listeners with normal and impaired hearing.
abstract: Forward-masked thresholds increase as the magnitude of inherent masker envelope fluctuations increase for both normal-hearing (NH) and hearing-impaired (HI) adults for a short masker-probe delay (25 ms). The slope of the recovery from forward masking is shallower for HI than for NH listeners due to reduced cochlear nonlinearities. However, effects of hearing loss on additional masking due to inherent envelope fluctuations across masker-probe delays remain unknown. The current study assessed effects of hearing loss on the slope and amount of recovery from forward maskers that varied in inherent envelope fluctuations. Forward-masked thresholds were measured at 2000 and 4000 Hz, for masker-probe delays of 25, 50, and 75 ms, for NH and HI adults. Four maskers at each center frequency varied in inherent envelope fluctuations: Gaussian noise (GN) or low-fluctuation noise (LFN), with 1 or 1/3 equivalent rectangular bandwidths (ERBs). Results suggested that slopes of recovery from forward masking were shallower for HI than for NH listeners regardless of masker fluctuations. Additional masking due to inherent envelope fluctuations was greater for HI than for NH listeners at longer masker-probe delays, suggesting that inherent envelope fluctuations are more disruptive for HI than for NH listeners for a longer time course.
authors.affiliation: Department of Speech-Language-Hearing Sciences, University of Minnesota, 164 Pillsbury Drive Southeast, Minneapolis, Minnesota 55455, USA.
authors.forename: Adam
authors.initials: A
authors.lastname: Svec
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, MSC 550, Charleston, South Carolina 29425, USA.
authors.forename: Judy R
authors.initials: JR
authors.lastname: Dubno
authors.affiliation: Department of Speech-Language-Hearing Sciences, University of Minnesota, 164 Pillsbury Drive Southeast, Minneapolis, Minnesota 55455, USA.
authors.forename: Peggy B
authors.initials: PB
authors.lastname: Nelson
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D001307:Auditory Perception; D001309:Auditory Threshold; D016022:Case-Control Studies; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise / Q000009:adverse effects*; D010470:Perceptual Masking; D019986:Persons with Hearing Disabilities / Q000523:psychology*; D013997:Time Factors; D055815:Young Adult