title: Sensorineural hearing loss enhances auditory sensitivity and temporal integration for amplitude modulation.
abstract: Amplitude-modulation detection thresholds (AMDTs) were measured at 40 dB sensation level for listeners with mild-to-moderate sensorineural hearing loss (age: 50-64 yr) for a carrier frequency of 500 Hz and rates of 2 and 20 Hz. The number of modulation cycles, N, varied between two and nine. The data were compared with AMDTs measured for young and older normal-hearing listeners [Wallaert, Moore, and Lorenzi (2016). J. Acoust. Soc. Am. 139, 3088-3096]. As for normal-hearing listeners, AMDTs were lower for the 2-Hz than for the 20-Hz rate, and AMDTs decreased with increasing N. AMDTs were lower for hearing-impaired listeners than for normal-hearing listeners, and the effect of increasing N was greater for hearing-impaired listeners. A computational model based on the modulation-filterbank concept and a template-matching decision strategy was developed to account for the data. The psychophysical and simulation data suggest that the loss of amplitude compression in the impaired cochlea is mainly responsible for the enhanced sensitivity and temporal integration of temporal envelope cues found for hearing-impaired listeners. The data also suggest that, for AM detection, cochlear damage is associated with increased internal noise, but preserved short-term memory and decision mechanisms.
authors.affiliation: UMR CNRS LSP 8248, Institut d'Etude de la Cognition, Ecole normale supérieure, Paris Sciences et Lettres Research University, 29 rue d'Ulm, 75005 Paris, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Wallaert
authors.affiliation: Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, United Kingdom.
authors.forename: Brian C J
authors.initials: BC
authors.lastname: Moore
authors.affiliation: Medizinische Physik and Cluster of Excellence Hearing4All, Universität Oldenburg, 26111 Oldenburg, Germany.
authors.forename: Stephan D
authors.initials: SD
authors.lastname: Ewert
authors.affiliation: UMR CNRS LSP 8248, Institut d'Etude de la Cognition, Ecole normale supérieure, Paris Sciences et Lettres Research University, 29 rue d'Ulm, 75005 Paris, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Lorenzi