Cognitive disturbances in cerebellum infarctions

The influence of the cerebellum on cognitive functions (CF) is poorly known and understudied so far. Neurological, neuropsychological and neuroimaging non-randomized study was carried out in 25 patients (14 women, 11 men, mean age 51.8+/-18.0 years) with isolated cerebellum infarctions. Cognitive disturbances (CD) were detected in 22 (88%) patients. They included impairment of attention, planning, control, abstract reasoning, memory; speech (naming, fluency, agrammatism, dysprosodia), special visual, quasi-spatial and counting disorders that indicated dysfunction of the anterior and posterior associative areas of the brain cortex. The expression of CD was different: being clinically obvious in 6 patients (24%), they were found only by neuropsychological methods in 16 patients (64%). Clinically significant CD developed in the lesions of certain areas (posterior-lower-lateral and posterior-medial) of the cerebellum hemisphere related to the dominant brain hemisphere. The presence of these CD did not depend on infarctions size: in expressed CD it was smaller (mean 5.65 cm(3)) than in other cases (mean 12.8 cm(3)). Typical appearances of cerebellum infarction (ataxia, vertigo, vomiting) were observed in all the patients with clinically non-significant CD and only in 2 out of 6 with clinically significant CD. The study demonstrated a role of the cerebellum in CF modulation. The expression of CD in cerebellum infarctions depends on their localization. Topic localization of the cerebellum areas, controlling CD and movement, is different.