Psychiatric syndromes in cerebellar degeneration

The role of the cerebellum in both normal and abnormal processes has undergone substantial reassessment over the past several years. Although the cerebellum's role has traditionally been considered the coordination of voluntary movements, increasing evidence now supports its role in the modulation of cognitive and emotional processing. We review both earlier anecdotal clinical data and newer systematic studies that detected psychiatric changes in patients with cerebellar degeneration (CD); these findings are consistent with observations in other neurodegenerative diseases. Our own data reveal high rates of mood disorders, personality change, psychosis, and cognition in patients with degenerative diseases affecting the cerebellum. These findings have important clinical implications in the management of these patients. In addition, the demonstration that psychiatric disorders may be the consequence of degenerative diseases affecting the cerebellum provides an insight into the neuroanatomical basis for psychopathology, and provides further validation of the general concept that many psychiatric syndromes are rooted in the brain.