Vowel-speech versus pure-tone processing in healthy subjects

Abstract To investigate the characteristics of speech perception, we evaluated the differences in mismatch negativity (MMN) between vowel change and frequency change. Additionally, we examined the effects of gender, age, and educational length on MMN. Forty healthy adults (21 females), who were native Japanese speakers, participated in the study. A Japanese vowel-speech pair (standard/a/vs. deviant/o/) and a pure-tone pair (standard 1000 Hz vs. deviant 1050 Hz) were constructed. MMN elicited by vowel-speech sounds was larger and earlier compared with pure-tone sounds. Larger and earlier MMNs for vowel-speech sounds than for pure-tone sounds suggest different processing of linguistically relevant information at the early stage in the auditory cortex. In conclusion, the factors influencing on MMN are different between vowel-speech sounds and pure-tone sounds.