Age-and height-dependent changes of amplitude and latency of somatosensory evoked potentials in children and young adults with Down's syndrome.

Middle-latency somatosensory evoked potentials (MLSEPs) were recorded from 19 scalp electrodes in 34 patients with Down's syndrome (DS) aged 7.4 to 35.7 years and in 16 normal control subjects aged 6.4 to 34.4 years. DS patients showed an increase in amplitude of P22, P45, and N60. P100 latency was significantly shortened. After normalization for height of subjects, N20 and N60 latencies were significantly longer in the patient group than in control subjects. On the other hand, it was possible to observe in both groups a significant trend for MLSEP amplitudes to decrease with age during the age period considered in this work. This study further confirms that the pattern of increase in amplitude of MLSEP components observed in DS is a finding peculiar of this syndrome and is not correlated with early aging processes.