and thus are well suited for investigations of the levels of cognitive processing required for reading. ERPs have been shown to be valuable in the study of normal cognitive development, as well as in the investigation of cognitive disturbances in childhood (e.g. Martineau et al ., 1992; Stauder et al ., 1993; Taylor, 1995). Most studies were devoted to `classical' electrophysiological events such as mismatch negativity (MMN), P300 and N400 (for a review of peculiarities of ERPs in childhood, see Taylor, 1995). However, some works also described abnormalities of earlier events such as N1, P2 or N2 in dyslexic or LLI children, but these will not be reviewed here. MMN The MMN is an ERP characterized by a negative deflection with a frontocentral distribution, that peaks between 100 and 250 ms after stimulus onset. The MMN is thought to be generated in the supratemporal auditory cortex and is elicited in situations where any physically deviant auditory stimulus occurs randomly and infrequently in a series of homogeneous, or standard, stimuli ( Ntnen et al ., 1978 ). It can be elicited independent of attention and by very small acoustic changes. The MMN therefore reflects an automatic `change-detection response' ( Kraus et al ., 1995 ) and may be used to investigate, at a pre-attentive level, whether the auditory system has distinguished between two stimuli. Using the MMN evoked response, Kraus and her colleagues have obtained evidence suggesting auditory deficits in certain children with learning problems ( Kraus et al ., 1996