Bisensory augmentation: a speechreading advantage when speech is clearly audible and intact.

Reisberg, McLean, and Goldfield (1987) have shown that vision plays a part in the perception of speech even when the auditory signal is clearly audible and intact. Using an alternative method the present study replicated their finding. Clearly audible spoken messages were presented in audio-only and audio-visual conditions, and the adult participants' resulting comprehension was measured. Stories were presented in French (Expt 1), in a Glaswegian accent (Expt 2), and by presenting spoken information that was semantically and syntactically complex (Experiment 3). Three separate groups of 16 adult female participants aged 19-21 participated in the three experiments. In all three experiments, comprehension improved significantly when the speaker's face was visible.