Differences in movement - related cortical activation patterns 1 underlying motor performance in children with and without Developmental

24 Behavioral deficits in visuomotor planning and control exhibited by children with 25 Developmental Coordination Disorder (DCD) have been extensively reported. Although 26 these functional impairments are thought to result from “atypical brain development,” 27 very few studies, to date, have identified potential neurological mechanisms. To address 28 this knowledge gap, electroencephalography (EEG) was recorded from 6to 12-year old 29 children with and without DCD (n = 14 and 20, respectively) during the performance of a 30 visuomotor drawing task. With respect to motor performance, TD children exhibited age31 related improvements in key aspects of motor planning and control. Although some 32 children with DCD performed outside this typically developing (TD) landscape (i.e., age33 related changes within the TD group), the group developmental trajectory of the children 34 with DCD was similar to that of the TD children. Despite overall similarities in 35 performance, engagement of cortical resources in the children with DCD was markedly 36 different from their TD counterparts. While the patterns of activation are stable in the TD 37 children across the age range, the young children with DCD exhibited less engagement of 38 motor cortical brain areas and the older children with DCD exhibited greater engagement 39 of motor cortical brain areas than their TD peers. These results suggest that older children 40 with DCD may employ a compensatory strategy in which increased engagement of 41 relevant motor resources allow these children to perform comparably to their TD peers. 42 Moreover, the magnitude of activation was related to several kinematic measures, 43 particularly in children with DCD, suggesting that greater engagement in motor resources 44 may underlie better behavioral performance. 45 46 EEG and Motor Performance DCD 3