Cerebellar perfusion abnormalities correlated with change in cognitive and affective state in a 78-year-old man

The onset of dementia is often recognized to some extent by those affected with this slow, degenerative process. Patients often have comorbid mood and/or anxiety disorders as a result of or in addition to this recognition. The author describes an unusual presentation for dementia, in both its onset and its correlation with regional changes in cerebral and cerebellar blood flow, as detected with whole-brain, voxel-by-voxel analysis. This patient's ultra-rapid cycling from severe disability to a state of near-normalcy was associated with a normalization of a flow deficit in the right posterior-parietal region, in addition to striking increases in the already over-perfused cerebellum. The author summarizes possible mechanisms for these flow changes and gives a brief review of recent literature on the involvement of the cerebellum in cognition.