AUDITORY-DISCRIMINATION IN INFANTS AS REVEALED BY THE MISMATCH NEGATIVITY OF THE EVENT-RELATED BRAIN POTENTIAL

In adults, deviant sounds occurring among repetitive standard sounds e licit the mismatch negativity (MMN) component of auditory event-relate d brain potential (ERP) even when these sounds are not attended to. MM N appears to be generated in the auditory cortex by a comparison proce ss between deviant auditory input and a neuronal sensory-memory trace that is formed by the repetitive standard stimuli and which represents their physical features. Recent ERP studies have shown that MMN is al so elicited in newborns and in older infants by physical changes in si mple tones, as well as by changes in phonemes. Thus, MMN might provide a new tool for objective assessment of normal and deficient developme nt of auditory discrimination, sensory memory, and speech perception i n infants.