Neurophysiological and neuropsychological differences related to performance and verbal abilities in subjects with mild intellectual disability

The present study compared two group of subjects with intellectual disabili ty. The 44 subjects in group 1 had equivalent verbal and performance IQs (6 7 and 64, respectively), while the ra subjects in group 2 had an intellectu al performance IQ which was greater than or equal to 10 points above their verbal performance IQ (80 and 65, respectively). The second group showed an alpha peak at a higher frequency and an evoked potential closer to normali ty. The decrease in the voltage of the P300 wave in group I was especially significant. The cognitive evoked potentials were also different between th e two groups.