MATURATION OF MISMATCH NEGATIVITY IN INFANTS

The mismatch negativity (MMN) is a pre-attentive change-specific compo nent of the event-related brain potentials (ERPs). During the last dec ade this response has been intensively studied in adults, but investig ations in children and especially in infants are still rare. Recent st udies, however, have shown that MMN is also elicited in infants in res ponse to changes in pure tones as well as in phonemes. The present stu dy compared MMN in pre-term infants (conceptional age at the time of r ecording, 30-35 weeks), full-term newborns and full-term 3-month-old i nfants. Stimuli were Klatt-synthesized Finnish vowels /y/ and /i/. Pre vious studies have reported larger MMN amplitudes in school-age childr en compared with those obtained in adults. According to the results, h owever, the infant MMN amplitude seems to resemble that of adults. No significant differences in MMN amplitudes were found between the three age groups either. The mean MMN latency, however, decreased significa ntly with age, although in 3-month-old infants it was not much longer than in a previous study conducted in adults with the same stimuli. (C ) 1998 Elsevier Science B.V.