What is the functional anatomy of the cerebellum?
- Three sagittal divisions: the left and right hemispheres and vermis. This segregation helps describe cerebellar syndromes
|Clinical Syndrome||Region(s) Involved||Distribution of Deficits||Common Causes||Other Features|
|Rostral vermis||Anterior and superior vermis, includes fastigial nucleus||Wide-based stance|
Gait ataxia with little ataxia on heel to shin
Normal or only slightly impaired arm coordination
|Alcoholism (affects Purkinje cells)|
|Infrequent presence of hypotonia, nystagmus, and dysarthria|
|Caudal vermis||Superior vermis and flocculonodular lobe||Axial disequilibrium, ataxic gait, and little or no limb ataxia||Neoplasm (e.g., medulloblastoma, especially in children)||Sometimes spontaneous nystagmus and rotated postures of the head|
|Lateral zone||Cerebellar hemisphere||Ipsilateral dysfunction:|
Ocular movement abnormalities
|Lesions (e.g., infarct, neoplasm, abscess)||Tremor if dentate nucleus involved|
No balance or gait disorder
|Pancerebellar||All areas||Bilateral signs of cerebellar dysfunction||Infectious/parainfectious causes, toxic/metabolic, paraneoplastic cerebellar syndromes, hereditary cerebellar degenerations||—|
Three transverse divisions correspond to major lobes, separated by fissures: the anterior, posterior, and flocculonodular lobes
- Three pairs of midline nuclei organized from medial to lateral are the fastigial, nucleus interpositus (containing the emboliform and globose nuclei), and the dentate nucleus.
- • Three paired cerebellar peduncles contain the information flow to and from the cerebellum: the superior (a.k.a. brachium conjunctivum, SCP), the middle (a.k.a. the brachium pontis, MCP) and the inferior cerebellar peduncles (a.k.a. restiform body, ICP).