Cerebellar

Cerebellar is an anatomical term describing anything related to the cerebellum, a major structure located at the back of the brain beneath the occipital lobes and behind the brainstem. The cerebellum consists of two hemispheres connected by a midline vermis and communicates with other parts of the brain via three cerebellar peduncles (superior, middle, and inferior).

It plays a key role in coordinating voluntary movement, maintaining balance and posture, and refining motor activity through motor learning. It integrates sensory input with motor commands from the cerebral cortex and brainstem and projects its influence to motor areas through deep cerebellar nuclei and thalamic pathways.

Cerebellar dysfunction produces characteristic signs, including ataxia (uncoordinated movement), dysmetria (range error in reaching), dysdiadochokinesia, intention tremor, gait instability, and nystagmus. Hypertonia or hypotonia can occur, depending on the lesion stage and location. Lesions may be due to stroke (often involving the posterior inferior cerebellar artery or superior cerebellar artery territory), hemorrhage, tumor, infection, inflammation, or neurodegenerative diseases such as spinocerebellar ataxias.

Clinical assessment may involve neurological examination and imaging, with MRI being preferred to identify cerebellar infarcts, hemorrhages, or atrophy. The term cerebellar is used in a wide range of contexts, including cerebellar cortex, cerebellar hemispheres, cerebellar peduncles, cerebellar ataxia, and cerebellar degeneration.