An evaluation of cortical preparatory and peripheral muscle activity in movement-evoked pain

Pain is a significant contributor to the development and potential persistence of motor dysfunction. A critical limitation to our understanding of motor related pain arises from measurements that overlook the contribution of movement in evoking pain. There is a pressing need to understand the influence of movement-evoked pain on motor system function during the stages of movement generation in pain inducing movements. The objectives of this thesis were two-fold. First, we aimed to examine how movement evoked pain influences cortical preparatory processes, muscle activity, and force/rate of force production (RFD) in healthy adults. Secondly, we aimed to explore whether cortical preparatory and peripheral changes persist in subsequent pain-free movement. Cortical preparatory activity was examined by the changes in event-related desynchronization (ERD) of beta (13-30 Hz) oscillatory activity and the movement-related cortical potential (MRCP) using electroencephalography (EEG) during a movement-evoked pain intervention. In addition, peripheral activity was assessed using electromyography (EMG), torque, and the rate of force development (RFD). These measures provide information about sensorimotor cortical activation and the cognitive factors that are involved in the preparation of movements that evoke pain. Peripheral measures provide complementary information on the pain induced adaptions to central motor pathways. The results showed a lack of change in beta ERD, an increase in the MRCP, and no changes in muscle activity and RFD with movements that evoked brief pain. Furthermore, there was no persistent change in any of these measures during subsequent pain-free movement. Transient movement-evoked pain changes aspects of preparatory corticomotor and peripheral activity; however, context dependent increases in the MRCP suggests that cognitive factors influence how the body adapts to the performance of movements that evoke pain.Education, Faculty ofKinesiology, School ofGraduat