We performed MRI on 57 socially active, healthy people without neurologic signs or symptoms when admitted to our hospital for a routine medical evaluation. Of these, 34 persons had patchy white matter lesions (PWMLs). Mild lesions were distributed mainly around the anterior horns or the bodies of the lateral ventricles. However, more severe lesions were distributed widely, involving both the anterior halves of the brains and the regions around the posterior horns. The mean total and LDL cholesterol levels were higher in healthy individuals with PWMLs than in those without them. No other significant difference between the groups was found.