TY - JOUR T1 - Motor learning enhances use-dependent plasticity JF - The Journal of Neuroscience JO - J. Neurosci. DO - 10.1523/JNEUROSCI.3303-16.2017 SP - 3303-16 AU - Firas Mawase AU - Shintaro Uehara AU - Amy Bastian AU - Pablo Celnik Y1 - 2017/01/31 UR - http://www.jneurosci.org/content/early/2017/01/31/JNEUROSCI.3303-16.2017.abstract N2 - Motor behaviors are shaped not only by current sensory signals but also by the history of recent experiences. For instance, repeated movements toward a particular target bias the subsequent movements toward that target direction. This process, called use-dependent plasticity (UDP), is considered a basic and goal-independent way of forming motor memories. Most studies consider movement history as the critical component that leads to UDP (Classen et al., 1998, Verstynen and Sabes, 2011). However, the effects of learning (i.e. improved performance) on UDP during movement repetition have not been investigated. Here, we used transcranial magnetic stimulation (TMS) in two experiments to assess plasticity changes occurring in the primary motor cortex (M1) after individuals repeated reinforced and non-reinforced actions. The first experiment assessed whether learning a skill task modulates UDP. We found that a group that successfully learned the skill task showed greater UDP than a group that did not accumulate learning, but made comparable repeated actions. The second experiment aimed to understand the role of reinforcement learning in UDP while controlling for reward magnitude and action kinematics. We found that providing subjects with a binary reward without visual feedback of the cursor, led to increased UDP effects. Subjects in the group that received comparable reward, but that was not associated with their actions and therefore did not show improved performance, maintained the previously induced UDP. Our findings illustrate how reinforcing consistent actions strengthens use-dependent memories and provide insight into operant mechanisms that modulate plastic changes in the motor cortex.Significant statementPerforming consistent motor actions induces use-dependent plastic changes in the motor cortex. This plasticity reflects one of the basic forms of human motor learning. Past studies assumed that this form of learning is exclusively affected by repetition of actions. However, here we showed that success-based reinforcement signals could affect the human use-dependent plasticity (UDP) process. Our results indicate that learning augments and interacts with use-dependent plasticity. This effect is important to the understanding of the interplay between the different forms of motor learning and suggests that reinforcement is not only important to learning new behaviours, but can shape our subsequent behaviour via its interaction with UDP. ER -