Visual (VEP) and somatosensory (SSEP) evoked potentials in Huntington's chorea

In 13 patients suffering from Huntington's chorea (H.Ch.) VEPs and SSEPs were investigated in comparison with 9 clinically unaffected offsprings and 40 normal adults. (1) The mean amplitude of VEPs was reduced in all patients and in 4 out of 9 offsprings. (2) Latencies of P100 in VEPs were normal in all subjects. (3) The late components were reduced in amplitude and rather irregular in shape. (4) The latencies of SSEPs were slightly prolonged, less marked in the early peaks and more pronounced in the later ones. (5) The late components after 70--100 msec were often attenuated or even absent. (6) The mean amplitude of P1/N2 was remarkably reduced. (7) Interhemispheric asymmetries were pronounced in 3 out of 9 offsprings.