Neurodegeneration and the Cerebellum

<b><i>Background:</i></b> The cerebellum modulates diverse neuronal networks, regulating motor, cognitive, behavioral, and limbic circuits. Structural and functional changes to the cerebellum that occur with neurodegenerative conditions have not been systematically reviewed. <b><i>Objective:</i></b> We synthesize the current understanding of cerebellar somatotopy and function with previously described cerebellar changes in neurodegenerative diseases not associated with primary cerebellar pathology. <b><i>Methods:</i></b> A thorough literature review defines the role of the cerebellum in normal function and neurodegeneration, and we additionally provide exemplar cases of cerebellar dysfunction in neurodegenerative disorders. <b><i>Results:</i></b> Comparisons between normal function and neurodegenerative disease states emphasize how normal organization of the cerebellum is altered in neurodegenerative disease states. We illustrate key anatomic structures using novel cerebellar segmentation tools and images. <b><i>Conclusions:</i></b> Altered cerebellum in neurodegeneration can provide important diagnostic and pathologic insights into both predicting disease progression and network dysfunction.