A wealth of evidence describes the strong positive impact that reward has on motor control at the behavioural level. However, surprisingly little is known regarding the neural mechanisms which underpin these effects, beyond a reliance on the dopaminergic system. In recent work, we developed a task that enabled the dissociation of the selection and execution components of an upper limb reaching movement. Our results demonstrated that both selection and execution are concommitently enhanced by immediate reward availability. Here, we investigate what the neural underpinnings of each component may be. To this end, we aimed to alter the cortical excitability of the ventromedial prefrontal cortex and supplementary motor area using continuous theta-burst transcranial magnetic stimulation (cTBS) in a within-participant design (N = 23). Both cortical areas are involved in determining an individual’s sensitivity to reward and physical effort, and we hypothesised that a change in excitability would result in the reward-driven effects on action selection and execution to be altered, respectively. To increase statistical power, participants were pre-selected based on their sensitivity to reward in the reaching task. While reward did lead to enhanced performance during the cTBS sessions and a control sham session, cTBS was ineffective in altering these effects. These results may provide evidence that other areas, such as the primary motor cortex or the premotor area, may drive the reward-based enhancements of motor performance.

大量证据描述了奖励在行为水平上对运动控制的强大积极影响。然而，除了对多巴胺能系统的依赖以外，对于支撑这些作用的神经机制知之甚少。在最近的工作中，我们开发了一项任务，该任务可以使上肢的选择和执行组件脱离运动。我们的结果表明，立即获得奖励可同时提高选择和执行力。在这里，我们研究了每个组件的神经基础。为此，我们的目的是在参与者内部设计中使用连续的θ-爆裂经颅磁刺激（cTBS）来改变腹侧前额叶皮层和辅助运动区的皮质兴奋性（N = 23）。两个皮层区域都参与确定个人对奖励和体力的敏感性，并且我们假设兴奋性的变化将导致奖励驱动的对动作选择和执行的影响分别发生改变。为了提高统计能力，会根据参与者对达成任务的奖励的敏感性预先选择参与者。尽管奖励确实在cTBS会话和控制假会话期间提高了性能，但cTBS在改变这些效果方面无效。这些结果可能提供证据，表明其他区域（例如初级运动皮层或运动前区域）可能会推动基于奖励的运动表现增强。