Lora Likova¹, Zhangiyi Zhou¹, Christopher Tyler¹, Kristyo Mineff¹; ¹Smith-Kettlewell Eye Research Institute

Traditionally associated with motor control and coordination, the cerebellum is increasingly recognized for its contributions to diverse cognitive processes. However, its specific cognitive roles and interactions with the cerebrum remain poorly understood and underexplored in the context of vision and cognition, highlighting the need for further investigation. Memory-guided drawing—a complex task engaging the full "perception-cognition-action loop"—provides a powerful framework for probing these mechanisms. Methods: Participants underwent whole-brain fMRI (Prisma 3T scanner) while drawing from visual-memory and performing additional tasks to isolate its key components: 1) Drawing from visual memory: Creating line drawings of complex spatial structures based on immediate visual memory; 2) Visual-memory recall: Visualizing images from immediate visual memory without drawing, to isolate memory and visualization processes; 3) Non-visual scribbling: Scribbling freehand blindfolded, to isolate visual motor control for drawing while excluding memory, cognition, and visual mechanisms; 4) Drawing from haptic memory: Drawing blindfolded from memory, to isolate haptic memory and coordination while excluding visual mechanisms. Granger Causal Connectivity Analysis (GCA) was used to investigate intracerebellar networks and their interactions with large-scale cortical networks. Results and Conclusions: The findings illuminate the cerebellum’s role in higher-order cognitive functions and its intricate functional architecture. Distinct cerebellar and cortical networks were revealed across tasks. Visual-memory-guided drawing elicited the most widespread and strong brain activation; notably, all cerebellar lobules—including non-motor regions—showed significant activity. Comparative analyses with the secondary component tasks provided novel insights into the cerebellum's perceptual-cognitive organization. GCA revealed causally directed cerebro-cerebellar interactions, involving both facilitative and suppressive feedback mechanisms. Particularly noteworthy were interactions with the Default Mode Network and other large-scale cortical networks. These results enhance our understanding of the cerebellum's integrative roles in perception, memory, cognition, and action, elucidating how its contribution extends far beyond motor coordination to encompass complex perceptual-cognitive operations.

Acknowledgements: NIH/NEI EY024056 & NSF SL-CN1640914 to L. Likova