title: Effects of spectral smearing on the identification of speech in noise filtered into low- and mid-frequency regions.
abstract: Léger et al. [J. Acoust. Soc. Am. 131, 1502-1514 (2012)] reported deficits in the identification of consonants in noise by hearing-impaired listeners using stimuli filtered into low- or mid-frequency regions in which audiometric thresholds were normal or near-normal. The deficits could not be fully explained in terms of reduced audibility or temporal-envelope processing. However, previous studies indicate that the listeners may have had reduced frequency selectivity, with auditory filters broadened by a factor of about 1.3, despite having normal or near-normal audiometric thresholds in the tested regions. The present study aimed to determine whether the speech-perception deficits could be explained by such a small reduction of frequency selectivity. Consonant identification was measured for normal-hearing listeners in quiet and in unmodulated and modulated noises using the same method as Léger et al. The signal-to-noise ratio was set to -3 dB for the masked conditions. Various amounts of reduced frequency selectivity were simulated using a spectral-smearing algorithm. Performance was reduced only for spectral-smearing factors greater than 1.7. For all conditions, identification scores for hearing-impaired listeners could not be explained by a mild reduction of frequency selectivity.
authors.affiliation: Equipe Audition, Institut d'Etudes Cognitives, École Normale Supérieure, Paris Sciences et Lettres, 29 rue d'Ulm, 75005 Paris, France. agnes.leger@ens.fr
authors.forename: Agnès C
authors.initials: AC
authors.lastname: Léger
authors.forename: Brian C J
authors.initials: BC
authors.lastname: Moore
authors.forename: Dan
authors.initials: D
authors.lastname: Gnansia
authors.forename: Christian
authors.initials: C
authors.lastname: Lorenzi
mesh_terms: D000465:Algorithms; D001309:Auditory Threshold / Q000502:physiology; D006801:Humans; D009622:Noise; D010469:Perceptual Distortion / Q000502:physiology*; D010470:Perceptual Masking / Q000502:physiology*; D010700:Phonetics; D059629:Signal-To-Noise Ratio; D013018:Sound Spectrography; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult