A brief history of the cerebellum

Abstract

Cerebellar structure and function have intrigued investigators and clinicians for millennia. Major anatomic features were recognized early, and the role of the cerebellum in coordinating movements was established two centuries ago. Cerebellar involvement in nonmotor functions was described in clinical and experimental observations starting around the same time, but attention to their importance rose to the fore only recently. Functional localization was fi rst derived from comparative morphology. Ablation degeneration and physiological studies in animals and neurological observations in patients with focal injury led to the lobular theory of organization. This was refi ned by delineation of the mediolateral parasagittal zonal organization of cerebellar connections. Histological studies date back to Cajal, with descriptions of additional neuronal elements and circuitry evolving over the years. Recognition of the cerebellar cognitive affective syndrome and the neuropsychiatry of the cerebellum, observations from connectional neuroanatomy, and advances in anatomic, task-based, and functional connectivity magnetic resonance neuroimaging provide contemporary support for the earliest notions that cerebellum is engaged in a wide range of neurological functions. Together with new theories of cerebellar function, and elucidation of the genetic basis of inherited or sporadic ataxias and neurobehavioral disorders, the cerebellum has become increasingly relevant to contemporary clinical neurology and neuropsychiatry.