Altered functional connectivity among frontal eye fields, thalamus and cerebellum in bipolar disorder.

OBJECTIVES The aim of our study is to evaluate functional connectivity of cerebellothalamo-cortical networks linking frontal eye fields (FEF) and cerebellar regions associated with oculomotor control: nodulus (X), uvula (IX), flocculus (H X) and ventral paraflocculus (H IX) in bipolar disorder (BD) with the use of resting state functional magnetic resonance imaging (rsfMRI). METHODS 19 euthymic BD patients and 14 healthy controls underwent rsfMRI examination. Functional connectivity between bilateral FEF, thalamus and cerebellar regions associated with oculomotor control was evaluated. RESULTS BD patients revealed decreased functional connectivity between following structures: right FEF and bilateral thalamus, flocculus (H X), uvula (IX); right thalamus and right FEF; between right flocculus (H X) and right FEF, left thalamus; between left thalamus and bilateral FEF and right flocculus (H X). CONCLUSIONS BD patients presented decreased functional connectivity among FEF, thalamus and cerebellar structures associated with eye movements control. Oculomotor evaluation of BD patients assessed with rsfMRI may help to determine whether altered functional connectivity observed in our study is associated with eye movements deficits in BD.