Sensorimotor network functional connectivity, proprioception, and visuomotor function in youth with hemiparetic cerebral palsy

Objectives Perinatal stroke (PS), a focal vascular brain injury near the beginning of life, can cause hemiparetic cerebral palsy (HCP) and lifelong disability for millions. Two PS subtypes, arterial ischemic stroke (AIS) and periventricular venous infarction (PVI), differ in timing and mechanism of injury and can both lead to HCP. HCP results in asymmetric motor and sensory impairments, including disruptions in proprioception (limb-position sense) and visuomotor coordination (visual information integration and movement execution). Sensorimotor integration is essential for motor development in children, and its disruption contributes to motor deficits in HCP. This study investigated resting-state functional connectivity (FC) in sensorimotor networks of youth with two different PS subtypes and its association with proprioceptive and visuomotor performance. Methods Resting-state fMRI was collected from children 6-19 years old with AIS or PVI and typically developing controls (TDC) (3.6 mm isotropic voxels, TR/TE=2000/30 ms, 150 volumes, 5 minutes). FC was assessed between primary motor cortex and other sensorimotor regions using the CONN toolbox. Proprioception and visuomotor coordination were evaluated using Kinarm robotic tasks. Mixed design analyses of covariance examined between-group and between-hemisphere FC differences, and between-group proprioception and visuomotor differences. Partial correlations assessed FC-behaviour associations, factoring out age. Results There were 112 participants (33 AIS, 36 PVI, 43 TDC; mean age 12.4 ± 3.0 years; 43% female). Participants with PS exhibited lower interhemispheric FC, and lower FC within the lesioned hemisphere compared to TDC. Within the PS subgroups, AIS showed lower FC than PVI, particularly in interhemispheric cortical and subcortical (basal ganglia) regions, while thalamic connectivity was similarly lower than controls in both groups. Task performance was positively correlated with sensorimotor FC in all groups, with the largest number of correlations in AIS, The fewest correlations occurred in controls. In addition, FC was correlated with multiple visuomotor outcomes mainly in AIS, but not TDC. Conclusion PS alters sensorimotor network organization. Subtype-specific differences in FC and FC-behaviour relationships suggest that lesion etiology influences developmental sensorimotor reorganization. Such imaging biomarkers may inform understanding of developmental sensorimotor connectivity and personalized rehabilitation strategies for youth with physical disabilities.