A prolonged (interictal) but reversible delirium was induced by
electroconvulsive therapy (ECT) in 10 of 87 (11%) elderly depressed
patients. Brain magnetic resonance imaging (MRI) revealed several
structural abnormalities, particularly basal ganglia and moderate to severe
subcortical white-matter lesions, in the patients who developed delirium.
These findings are consistent with several lines of data that have
implicated the basal ganglia and subcortical white matter in the
development of delirium from other causes and suggest that lesions in these
areas may predispose one to developing an interictal delirium during a
course of ECT.