Mapping Motor Preparation in the Developing Brain: Insights from Contingent Negative Variation and Event-related Mu Rhythm Modulation

IntroductionThe motor system shows a pronounced development throughout childhood and adolescence. The analysis of the contingent negative variation (CNV) provides valuable insights into various cognitive and motor processes, underlying cortical sources, and their development across the lifespan. MethodsWe investigated the maturation of motor preparation, pre-activation and post-processing in children and adolescents aged 5- to 16- years. EEG Data of 46 healthy right-handed subjects were recorded, using a 64-electrode high density sensor array. Subjects performed a CNV task with a directional warning cue. To assess age related developmental differences of cortical activation, analyses of event-related potentials (ERPs), mu-rhythm (de)synchronization and source analysis were applied. ResultsChildren showed increased reaction times and committed more errors than adolescent subjects. Motor preparation and post-processing were characterized by a developmental increase of cortical activity related to the supplementary motor area (SMA). Young children showed a pronounced sensory post processing during orienting response (early CNV) that decreased with age. In contrast to previous research in young adults, adolescent subjects showed no contralateral activation of motor areas during motor preparation (late CNV) yet. Furthermore, there was an observed decline in motor post processing with maturation. ConclusionThe results indicate a prolonged maturation of cortical scalp areas associated with motor control up into late adolescence or early adulthood. With age, the activation of mid-frontocentral regions associated with the SMA becomes more pronounced during motor planning and response evaluation. Qualitatively distinct cortical activation patterns of young subjects suggest immature supplementary-, pre- and primary motor areas and might be a primary cause for age-related increasing efficiency of motor action control.