The role of vision in the perception of speech.

The ability of hearing adolescents to use speech-read information in order to report lists of CVC words presented in white noise was investigated. The conditions of stimulus presentation included were auditory and visual information in synchrony, out of synchrony, auditory input alone, visual input alone, and a condition where the information presented in the auditory input conflicted with the visual input. The results indicated that the amount and type of type of information reported varied according to the condition of presentation, and that vision provided a complementary source of information for the perception of speech.