Third International Conference on Spoken Language Processing (ICSLP 94)
We used the 'gating' method to study the perception of both auditory and visual speech on the phoneme level . We investigated at which moments during the presentation of phonemes humans are able to correctly identify some or all of their phonetic features. The results indicated that the visual information about place of articulation is available for perceptual processing sooner than is the auditory information about place, manner of articulation and voicing. A plausible explanation seems to be that this difference is related to the difference in onset time between the visual and the acoustical speech signal. It does not seem necessary to assume substantial differences in processing times for the auditory and the visual modality.
Bibliographic reference. Smeele, Paula M. T. / Sittig, Anne C. / Heuven, Vincent J. van (1994): "Temporal organization of bimodal speech information", In ICSLP-1994, 1431-1434.