Abstract
To evaluate the intellectual function of Duchenne muscular dystrophy (DMD) with event related potentials (ERP), P300 and mismatch negativity (MMN) were recorded in 15 patients with DMD (aged 15-31). Cortical potentials were recorded with surface electrodes from Fz, Cz and Pz with A1+A2 reference. P300 was recorded using oddball two-tone discrimination paradigm (target: 2 kHz, non-target: 1kHz) counting the number of target tones, and the probability of the target tones was 15%. MMN was obtained by subtructing the potentials to the frequent tones (1kHz, 85%) from the potentials to the rare tones (2 kHz, 15%). Patients were required to ignore the auditory stimuli.
P300 was abnormal in 5 of 15 patients examined, but early components of this ERP, N1 and N2, were normal, and MMN was normal in all patients. There was no significant difference in MMN between the patients who showed normal P300 and the patients who showed abnormal P300. These results suggest that the later process (controlled process) of cognitive function presented by P300 is impaired, but early and automatic process of cognitive function is hardly affected in DMD.
