Brainstem and cerebellar activation during horizontal and vertical optokinetic stimulation in fMRI

Earlier fMRI studies during horizontal optokinetic nystagmus (OKN) showed bilateral activations of a cortical network in the primary visual cortex, motion-sensitive areas in the temporo-occipital cortex as well as in cortical eye fields [1, 2]. Due to earlier technical limitations the studies were restricted to the cortex. From animal studies it is known that certain brainstem nuclei and cerebellar areas are involved in the processing of ocular motor responses. The aim of this study was to identify and differentiate brainstem and cerebellar areas involved in the generation of horizontal (hOKN) and vertical OKN (…