title: Visual speech improves the intelligibility of time-expanded auditory speech.
abstract: This study investigated the effects of intermodal timing differences and speed differences on word intelligibility of auditory-visual speech. Words were presented under visual-only, auditory-only, and auditory-visual conditions. Two types of auditory-visual conditions were used: asynchronous and expansion conditions. In the asynchronous conditions, the audio lag was 0-400 ms. In the expansion conditions, the auditory signal was time expanded (0-400 ms), whereas the visual signal was kept at the original speed. Results showed that word intelligibility was higher in the auditory-visual conditions than in the auditory-only condition. The results of auditory-visual benefit revealed that the benefit at the end of words declined as the amount of time expansion increased, although it did not decline in the asynchronous conditions.
authors.affiliation: Research Institute of Electrical Communication, Tohoku University, Sendai, Japan. a.tanaka@uvt.nl
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tanaka
authors.forename: Shuichi
authors.initials: S
authors.lastname: Sakamoto
authors.forename: Komi
authors.initials: K
authors.lastname: Tsumura
authors.forename: Yôiti
authors.initials: Y
authors.lastname: Suzuki
mesh_terms: D000161:Acoustic Stimulation; D000704:Analysis of Variance; D001307:Auditory Perception; D005145:Face; D006801:Humans; D010775:Photic Stimulation; D013065:Speech Intelligibility; D013067:Speech Perception; D014796:Visual Perception; D055815:Young Adult