title: A psychophysical imaging method evidencing auditory cue extraction during speech perception: a group analysis of auditory classification images.
abstract: Although there is a large consensus regarding the involvement of specific acoustic cues in speech perception, the precise mechanisms underlying the transformation from continuous acoustical properties into discrete perceptual units remains undetermined. This gap in knowledge is partially due to the lack of a turnkey solution for isolating critical speech cues from natural stimuli. In this paper, we describe a psychoacoustic imaging method known as the Auditory Classification Image technique that allows experimenters to estimate the relative importance of time-frequency regions in categorizing natural speech utterances in noise. Importantly, this technique enables the testing of hypotheses on the listening strategies of participants at the group level. We exemplify this approach by identifying the acoustic cues involved in da/ga categorization with two phonetic contexts, Al- or Ar-. The application of Auditory Classification Images to our group of 16 participants revealed significant critical regions on the second and third formant onsets, as predicted by the literature, as well as an unexpected temporal cue on the first formant. Finally, through a cluster-based nonparametric test, we demonstrate that this method is sufficiently sensitive to detect fine modifications of the classification strategies between different utterances of the same phoneme.
authors.affiliation: Lyon Neuroscience Research Center, CNRS UMR 5292, Auditory Language Processing (ALP) research group, Lyon, France; Laboratoire sur le Langage le Cerveau et la Cognition, CNRS UMR 5304, Auditory Language Processing (ALP) research group, Lyon, France; Université de Lyon, Université Lyon 1, Lyon, France.
authors.forename: Léo
authors.initials: L
authors.lastname: Varnet
authors.affiliation: Stem Cell and Brain Research Institute, INSERM U 846, Integrative Neuroscience Department, Bron, France.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Knoblauch
authors.affiliation: Université Libre de Bruxelles, UNESCOG, CP191, Bruxelles, Belgique.
authors.forename: Willy
authors.initials: W
authors.lastname: Serniclaes
authors.affiliation: Laboratoire sur le Langage le Cerveau et la Cognition, CNRS UMR 5304, Auditory Language Processing (ALP) research group, Lyon, France; Université de Lyon, Université Lyon 1, Lyon, France.
authors.forename: Fanny
authors.initials: F
authors.lastname: Meunier
authors.affiliation: Lyon Neuroscience Research Center, CNRS UMR 5292, Auditory Language Processing (ALP) research group, Lyon, France; INSERM U1028, Lyon Neuroscience Research Center, Brain Dynamics and Cognition Team, Lyon, France; Université de Lyon, Université Lyon 1, Lyon, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Hoen
mesh_terms: D000465:Algorithms; D003463:Cues; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D011571:Psychoacoustics; D059629:Signal-To-Noise Ratio; D013060:Speech; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult