title: Impact of Audio-Visual Asynchrony on Lip-Reading Effects -Neuromagnetic and Psychophysical Study.
abstract: The effects of asynchrony between audio and visual (A/V) stimuli on the N100m responses of magnetoencephalography in the left hemisphere were compared with those on the psychophysical responses in 11 participants. The latency and amplitude of N100m were significantly shortened and reduced in the left hemisphere by the presentation of visual speech as long as the temporal asynchrony between A/V stimuli was within 100 ms, but were not significantly affected with audio lags of -500 and +500 ms. However, some small effects were still preserved on average with audio lags of 500 ms, suggesting similar asymmetry of the temporal window to that observed in psychophysical measurements, which tended to be more robust (wider) for audio lags; i.e., the pattern of visual-speech effects as a function of A/V lag observed in the N100m in the left hemisphere grossly resembled that in psychophysical measurements on average, although the individual responses were somewhat varied. The present results suggest that the basic configuration of the temporal window of visual effects on auditory-speech perception could be observed from the early auditory processing stage.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.|Laboratory of Rehabilitative Auditory Science, Tohoku University Graduate School of Biomedical Engineering, Sendai, Miyagi, Japan.|Department of Audiology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
authors.forename: Tetsuaki
authors.identifier: http://orcid.org/0000-0001-5100-7331
authors.initials: T
authors.lastname: Kawase
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
authors.forename: Izumi
authors.initials: I
authors.lastname: Yahata
authors.affiliation: Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan.
authors.forename: Akitake
authors.initials: A
authors.lastname: Kanno
authors.affiliation: Research Institute of Electrical Communication, Tohoku University, Sendai, Miyagi, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Sakamoto
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Takanashi
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
authors.forename: Shiho
authors.initials: S
authors.lastname: Takata
authors.affiliation: Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
authors.forename: Nobukazu
authors.initials: N
authors.lastname: Nakasato
authors.affiliation: Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan.
authors.forename: Ryuta
authors.initials: R
authors.lastname: Kawashima
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Katori
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D001921:Brain / Q000502:physiology; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D008085:Lipreading; D015225:Magnetoencephalography; D008297:Male; D010775:Photic Stimulation; D011601:Psychophysics; D011930:Reaction Time; D014796:Visual Perception / Q000502:physiology*