University of Ottawa, Ottawa, Ontario, Canada
Cerebellar hypoplasia can be caused by congenital or post-natal viral infection or a genetic mutation, and leads to an underdeveloped cerebellum, motor dysfunction, and ataxia. Cerebellar dysfunction can also originate from neurodegenerative diseases. This affects the functional coupling of the cerebellum and multiple sensorimotor cerebral networks. Using resting-state fMRI, correlational studies have mapped cerebellar lobules to cerebral cortices and yielded models of cerebral-cerebellar interactions. This study investigated functional connectivity between cerebellar lobules focusing on sensorimotor regions by comparing task-based fMRI data from participants of an existing open-source dataset. To process and visualize the fMRI data, this study referenced anatomical and functional network atlases and used various statistical and computational software packages. Handedness was inferred from first-level functional connectivity analysis to create groups and performed second-level functional connectivity between-groups analysis. Statistically significant differences in functional connectivity between sensorimotor intracerebellar regions were identified, which may be attributable to differences in handedness. The present study showed that when compared to participants inferred to be left-handed or ambidextrous, participants inferred to be right-hand dominant had statistically significant differences in functional connectivity in specific sensorimotor regions, including lobules IV/V left to IV/V right when performing right-hand tasks, and lobules VIII left to III left when performing left-hand tasks. This finding informed the creation of a proposed right-hand sensorimotor intracerebellar model which may be visualized using various platforms. Through integrating causal and correlational imaging data to model intracerebellar connectivity, this study furthers research about the diagnosis and treatment of cerebellar hypoplasia and cerebellar dysfunction.
Abbreviations: FC – Functional Connectivity; fMRI – Functional Magnetic Resonance Imaging; gPPI – Generalized Psychophysiological Interactions; GUI – Graphical User Interface; MVPA – MultiVariate Pattern Analysis; ROI –Region of Interest
Keywords: Task-Based fMRI; Human Brain Imaging; Hand Dominance; Cerebellar Atlas; Motor Conditions; Regions of Interests; Network Connections; Computational Model