Poster A119, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C
Visual Field Representations in Human Cerebellum
James A. Brissenden1, Sean M. Tobyne1, David E. Osher2, Emily J. Levin3, Mark A. Halko4, David C. Somers1; 1Boston University, 2Ohio State University, 3Brown University, 4Harvard Medical School and Beth Israel Deaconess Medical Center
Maps of the visual field have been identified throughout the cerebral cortex. Visual field maps located in higher-order association areas such as the intraparietal sulcus and frontal eye fields are of particular interest as maps in these regions may serve as a critical substrate for spatial cognition. Recently, we showed that cerebellar lobules VIIb/VIIIa, which exhibit intrinsic connectivity with cortical attention areas, are recruited in a load-dependent fashion by visual attention and visual working memory tasks (Brissenden et al., JNeurosci., 2016). While somatotopic maps in the cerebellum are well characterized, cerebellar visual field maps have not been reported. To investigate whether visual field representations exist in cerebellum we conducted two fMRI experiments. In the first experiment, subjects performed an attentionally demanding visual field mapping task. A population receptive field (pRF) analysis found representations of the ipsilateral visual hemifield within lobules VIIb/VIIIa, consistent with the crossing of cortico-cerebellar fiber tracts. In the second experiment, subjects performed a lateralized visual working memory task. Stimuli were presented bilaterally and subjects were asked to covertly attend items in one visual hemifield. To determine whether the cerebellum is sensitive to the locus of attention, we trained support vector machines on cerebellar activity patterns to discriminate between the two possible locations of attentional deployment (left or right hemifield). A multivariate feature weight mapping analysis revealed clusters of informative voxels within lobule VIIb bilaterally. These results demonstrate the existence of visual field representations in human cerebellum and indicate that cerebellar lobules VIIb/VIIIa participate in visuospatial cognition.
Topic Area: ATTENTION: Spatial