Effect of uni- and multi-modal exercise interventions on visuo-motor functional connectivity in glaucoma patients and healthy elderly

MotivationGlaucoma is a progressive visual pathway disorder leading to visual field loss, which can be linked to disruptions in visuo-motor function and an increase in fall risk. Motor-cognitive training has been shown to affect visuo-motor functional connectivity (FC) in healthy controls (HC) and could therefore be a viable strategy for the management of glaucoma patients (GL). MethodsUsing 3T resting state functional-MRI (rs-fMRI), we studied the effect of a multimodal intervention (MMI [resistance + motor-cognitive dual-task training]) and unimodal intervention (UMI [resistance training only]) on rs-FC in 20 HC and 12 GL, randomly assigned to MMI (7GL, 9HC) and UMI (5GL, 11HC). Rs-fMRI was acquired pre- and post the 12-week intervention. Whole-brain FC were estimated with bilateral seeds in the visuo-motor pathway and paired longitudinal comparisons were performed to test effects of the interventions. ResultsLongitudinal effects of UMI were only observed in HC and were limited to an increase in FC between the cerebellum, midcingulate gyrus, and the frontal eye fields (pFWE<0.05). Interestingly, MMI had a widespread effect including an increase in FC within the visual pathway, between auditory and visual cortices, and with the motor cortex after MMI (pFWE<0.05) in both HC and GL. In addition, an increased FC between the dorsolateral prefrontal cortex, inferior frontal gyrus, sensorimotor cortex, and the inferior temporal gyrus (pFWE<0.05) was observed in GL after MMI. An increase in FC was also found between the cerebellum and the midcingulate gyrus (pFWE<0.05) in GL that underwent MMI. ConclusionOverall, our findings indicate a widespread effect of MMI in both HC and GL on rs-FC, highlighting cortical plasticity in GL. These results motivate further research on the effects of motor-cognitive interventions for visual pathway disorders like glaucoma.