Visual context effects on the perception of /r/ and /l/: Varying F1 and F2 acoustic characteristics

Context effects occur when the phonetic perception of an acoustic signal is modified by the surrounding phonetic context. Two experiments were conducted investigating visual context effects on the perception of acoustic speech tokens. In the first experiment a visual bilabial articulation [ibi] was paired with synthetic acoustic tokens from /iri/ to /ili/ continua. In the second experiment a visual [aba] was paired with tokens from synthetic /ara/ to /ala/ continua. Listeners were asked if they perceived the disyllables as containing an [r] or [l]. We found that auditory-visual identification functions were associated with a shift toward more [l] responses compared to auditory only identification functions. These data are important for developing and testing models of auditory-visual context effects in speech perception.