Patients with Hashimoto thyroiditis may have neurologic manifestations that have been described in the literature for some decades now; these include psychiatric disorders, abnormal movements, and simulation of cerebrovascular events. Nuclear magnetic resonance (MRI) studies have revealed diffuse leukoencephalopathy in most cases. We describe a case having clinical manifestations simulating cerebrovascular events, together with cognitive alterations (a presentation already described in other patients). Among the 2 main forms of neurologic manifestations, the cognitive type, which is probably associated with endocrinologic alteration, may improve with hormone supplement. Those alterations simulating cerebrovascular events are most probably related to autoimmune vasculitis. The latter may improve with the administration of corticosteroids, which are proposed as treatment of this disorder.