Does mismatch negativity show differences in reading-disabled children compared to normal children and children with attention deficit?

An auditory event-related potential (ERP) component called mismatch negativity (MMN) was examined in three groups of children (n = 63) aged 8-14 years. A control group comprised healthy children in second or sixth grade of comprehensive school (n = 21). The two clinical groups included children with reading disability (RD) (n = 21) and children with attention deficit (AD) (n = 21). MMN was elicited in a passive oddball paradigm by duration changes in a continuous sound, consisting of two alternating (600 and 800 Hz) 100 msec tones. The deviant tones were either 30 or 50 msec in duration. Both deviants elicited a clear MMN in all groups. Statistical analyses showed no systematic difference in the MMN peak latencies or amplitudes between the groups. A significant difference between the RD group and the control group was observed in the lateralization of the MMN peak amplitudes.