Cerebrovascular thalamic dementia: anatomical, clinical and neuropsychological correlates.

We assessed 19 patients with vascular thalamic lesions (9 haemorrhagic; 10 ischemic) using neuroimaging techniques (computed tomography and nuclear magnetic resonance imaging) and neuropsychological tests, including the Mini Mental State Examination, the Milan Overall Dementia Assessment, and the Clock Draw Test. The clinical and neuropsychological deficits were then correlated with the different thalamic regions involved. Patients with bilateral lesions showed behavioural disturbances, associated with marked neuropsychological deficits, and selective sensory-motor impairment, whereas patients with unilateral lesions showed less severe symptoms. All patients demonstrated apathy, cognitive impairment, drowsiness, and lack of insight. In patients with right thalamic lesions visuo-spatial attention and selective memory disturbances were predominant, while lesions affecting the left thalamic nuclei were associated with selective impairment of discriminative judgement, language, and abstract thought. Our study shows that right and left vascular thalamic lesions cause different cognitive and neuropsychological profiles, despite partial overlapping in frontal deficits associated with the classical clinical picture of thalamic dementia.