ELECTROENCEPHALOGRAM IN POSTENCEPHALITIC BEHAVIOR DISORDER AND POSTENCEPHALITIC PARKINSONISM

In a review of the electroencephalographic findings in patients with postencephalitic behavior disorder and postencephalitic parkinsonism, the following observations were made:

1. Of 15 cases with postencephalitic behavior disorder, 13 (87%) showed some electroencephalographic abnormalities, most of which were of a mild degree and of the slow wave type. There were 3 cases with a history of convulsive seizures as an added complication of the encephalitis. In 2 of these the tracings were markedly abnormal. These findings are consistent with the observations of others that in the behavior disorders associated with organic brain disease there is a relatively high incidence of electroencephalographic abnormality.

2. In a series of 36 cases with postencephalitic Parkinsonism, 11 (31%) showed some electroencephalographic abnormalities, which were all of mild degree and primarily of the slow wave type, although a moderate amount of fast activity was also observed.