Stimulus-Independent Attentional Modulation in Cerebellar Visual Regions

Spatial attention shapes neural activity across multiple cortical regions, and recent studies have demonstrated spatially selective attentional signals in cerebellar visual regions. However, it remains unclear whether these signals extend across the broader network of cerebellar visual representations and whether they share key functional properties of attentional modulation observed in cortical visual areas. Using fMRI, we measured brain activity in 50 participants (30 females) as they performed a covert spatial attention task in which attention was directed to the left or right visual hemifield, followed by visual stimuli of varying contrast or no stimulus. We showed that distributed activity patterns in the cerebellum reliably distinguished the attended hemifield, replicating previous findings of spatially selective attentional signals in Lobules VIIb/VIIIa and extending these findings to Lobule VI and Lobules VIIIb/IX/X. These regions largely overlapped with topographically organized cerebellar visual maps, indicating that attentional modulation operates within representations of visual space. Critically, attentional modulation was observed even in the absence of postcue stimulus presentation and was invariant across stimulus contrast, consistent with additive attentional effects previously described in cortical visual areas. We further identified nonspatial, stimulus-independent cerebellar attentional signals, suggesting contributions to attentional control beyond spatial selection. Finally, comparisons with motion-evoked responses revealed systematic differences across cerebellar visual regions in the relative contribution of attentional and sensory signals. Together, these findings demonstrate that spatially selective attention is represented across multiple cerebellar visual maps and shares functional properties with attentional modulation in cortical visual areas while revealing functional heterogeneity within the cerebellum.