Brain activation patterns underlying upper limb bilateral motor coordination in unilateral cerebral palsy: an fNIRS study

AIM To explore cortical activation during bimanual tasks and functional correlates in unilateral cerebral palsy (CP). METHOD This cross-sectional study included eight participants with unilateral CP (six females, two males; mean age [SD] 20y 10mo [5y 10mo], 13y 8mo-31y 6mo) in Manual Ability Classification System levels II to III and nine age-matched participants with typical development (seven females, two males; mean age [SD] 17y 8mo [5y 7mo], 9y 4mo-24y 2mo). They performed bimanual symmetric squeezing (BSS) and bimanual asymmetric squeezing (BAS) tasks at 1Hz, and a pouring task with dominant hand (DPour) and a pouring task with non-dominant hand (NDPour) at 0.67Hz, all while a custom array of functional near-infrared spectroscopy (fNIRS) optodes were placed over their sensorimotor area. Mixed-effects were used to contrast groups, tasks, and hemispheres (corrected p-values [q] reported). Analysis of variance and t-tests compared performance measures across groups and tasks. RESULTS Participants with unilateral CP showed greater activation in both hemispheres during BAS (non-lesioned: q