Influence of prior auditory and visual information on speech perception: Evidence from Japanese singleton and geminate words

The goal of this study was to demonstrate the influence of prior auditory and visual information on speech perception, using a priming paradigm to investigate the shift in the perceptual boundary of geminate consonants. Although previous research has shown visual information such as photographs influences the perception of spoken words, the effects of auditory and visual (written or illustrated) information have not been directly compared. In the present study, native Japanese speakers judged whether or not a spoken word was a geminate word after hearing/seeing a prime word/pseudoword that contained either singleton or geminate feature. The results indicate the spoken words, written words and even illustrations presented prior to the target sounds, can guide boundary shift for Japanese geminate perception. Significantly, the influence of auditory information is independent of the lexical status of the primes, that is, both word and pseudoword auditory primes with geminate sound features induced a significant bias. On the other hand, visual primes induced the bias only when the primes coincided lexically with the targets, indicating the influence of visual information on geminate perception is different from auditory information.