Audiovisual speech detection benefits: A comparison across psychophysical approaches

Visual speech reduces uncertainty as to when auditory speech will occur, thereby enhancing detection of speech in noise. These detection benefits reflect a low-level perceptual mechanism of AV speech enhancement that is independent of the linguistic nature of speech. Audiovisual speech detection benefits have primarily been assessed using two-interval forced-choice paradigms. Results from AV speech detection experiments using three different psychophysical approaches will be presented. These include a single-interval yes/no task, a go/no-go task, and a two-interval forced choice task. In all experiments, adults with normal hearing complete an auditory-only condition with a still image of the talker and an audiovisual condition with a synchronous and congruent visual speech signal. The audiovisual condition includes foil trials/intervals that force participants to use the auditory information to make the decision. Adults demonstrate significant audiovisual benefit to speech detection across all three task,...