Gamma-band Neural Synchronization is Associated with Motor Difficulties in Childhood Epilepsy

The present study used magnetoencephalographic (MEG) recordings during median nerve stimulation in children with epilepsy to investigate the hypothesis that abnormal inter-regional gamma-band synchronization within the sensorimotor network is related to motor performance difficulties. Stimulation-dependent gamma-band network synchronization following median nerve stimulation was identified by network based statistics (NBS) and involved the primary motor and somatosensory cortex. Lateralization of the synchronization network contralateral to the stimulated arm was observed and this lateralization was also found in the graph properties of strength, clustering and centrality of primary motor and somatosensory cortex. Significant associations between graph properties of primary motor and somatosensory cortex, reflecting the participation of these regions in the stimulation-dependent network, and motor performance in grooved pegboard and finger tapping tests for the contralateral hand were observed. These findings are congruent with the view that epilepsy may lead to performance deficits through the disruption of connectivity in functional brain networks.M.A