THE MISMATCH NEGATIVITY TO CHANGES IN SPEECH SOUNDS AT THE AGE OF 3 MONTHS

This study shows that an infrequent vowel(deviant) presented among fre quent vowels (standard) elicits in awake S-month-old infants a negativ ity in the auditory event-related potential resembling the mismatch ne gativity elicited by the same stimuli in previous studies in adults (A altonen, Niemi, Nyrke, & Tuhkanen, 1987) and newborns (Cheour-Luhtanen et al., 1995). The mismatch negativity amplitude for the deviant vowe ls was larger and the event-related potentials to standard stimuli wer e in general more positive in 3-month-old infants than in newborns, wh ich might reflect increased maturation of their nervous system relativ e to that of newborns.