MOTIVATION AND MOTOR CORTICAL ACTIVITY CAN INDEPENDENTLY AFFECT MOTOR PERFORMANCE

The present study explored the relationship between motor-preparatory electroencephalographic (EEG) activity, motivation, and motor performance (specifically pre-motor reaction time [RT]). Participants performed a RT task by squeezing a hand dynamometer in response to an auditory go signal. We recorded EEG and electromyography to index beta-suppression and premotor RT, respectively. Participants' motivation on each trial was modulated by offering monetary incentives at different magnitudes. Mixed-effect linear regression models showed that monetary incentive predicted premotor RT when controlling for beta-suppression, and beta-suppression independently predicted premotor RT. Thus, it appears motivation and beta-suppression can facilitate motor performance independent of one another. A plausible explanation of this effect is that motivation can affect motor performance independent of the motor cortex by influencing subcortical motor circuitry. (C) 2016 IBRO. Published by Elsevier Ltd. All rights reserved.