Differential cerebellar activation on functional magnetic resonance imaging during working memory performance in persons with multiple sclerosis

Li Y, Chiaravalloti ND, Hillary FG, DeLuca Liu W-C, Kalnin AJ, Ricker JH. Differential cerebellar activation on functional magnetic resonance imaging during working memory performance in persons with multiple sclerosis. Arch Phys Med Rehabil 2004;85:635-9. Objective To explore the potential role of the cerebellum in working memory dysfunction in multiple sclerosis (MS). Design Blood oxygen level dependent functional magnetic resonance imaging (fMRI) was used to examine cerebellar activation during a working memory task. Setting University-affiliated medical rehabilitation facility. Participants Eight persons with MS and 5 healthy controls. Interventions Not applicable Main outcome measure Change in hemodynamic response. fMRI data were acquired and subsequently analyzed by using Statistical Parametric Mapping. Results Both the control and MS groups showed significantly greater activations in the right cerebellar hemisphere as compared with the left side. Persons with MS, however, showed no detectable activations in 4 cerebellar substructures that were significantly active in controls (ie, right vermis, right dentate nucleus, right tonsil, cerebellar peduncle). Conclusions The significantly decreased cerebellar activation in the MS group suggests that the cerebellum may play a role in the working memory impairment observed in MS.