Recovery functions of somatosensory evoked potentials in parkinsonian patients.

The aim of this study was to analyze the recovery functions of median nerve somatosensory evoked potentials (SEPs) and to clarify changes in the somatosensory system of patients with Parkinson's disease (PD). The central and frontal SEPs and the nerve potential of the median nerve were examined. The latencies and amplitudes of SEPs produced by a single shock in patients with PD were normal. The recovery functions of central SEPs showed a low degree of suppression in patients with PD, although the recovery curve of the nerve potential in PD patients was almost normal. The change in recovery curves of SEPs in patients with sensory complaints were more noticeable than that in patients without sensory disturbance. A low degree of suppression of central SEPs might play a role in the sensory complaints of PD patients.