Integration of Audiovisual Speech and Priming Effects

Humans report fusion /da/ when presented with audio /ba/ aligned with visual /ga/. Over the last three decades most researchers have neglected the velar McGurk fusion: audio /ba/ with visual /da/ eliciting /ga/ fusion, and audio /pa/ with visual /ta/ resulting in /ka/ fusion. Cathiard [1], claimed that these latter types of fusion are laboratory curiosities which do not occur embedded in French VCV syllables. We conduct two experiments; in the first experiment, incongruent segment is embedded in real English words and in the second experiment we use a priming approach to bias the perception towards either the audio channel or the visual or the expected fusion. Results show that velar fusion perceptions are not just a product of isolated nonsense syllables, but are robust percepts formed by integration of audio and visual channels. Thus, using both types of McGurk fusion has potential to be used as a probing tool for exploring the phonological organization of lexical entities.