Electrical stimulation is a promising tool for modulating brain networks. However, it is unclear how stimulation interacts with neural patterns underlying behavior. Specifically, how might external stimulation that is not sensitive to the state of ongoing neural dynamics reliably augment neural processing and improve function? Here, we tested how low-frequency epidural alternating current stimulation (ACS) in non-human primates recovering from stroke interacted with task-related activity in perilesional cortex and affected grasping. We found that ACS increased co-firing within task-related ensembles and improved dexterity. Using a neural network model, we found that simulated ACS drove ensemble co-firing and enhanced propagation of neural activity through parts of the network with impaired connectivity, suggesting a mechanism to link increased co-firing to enhanced dexterity. Together, our results demonstrate that ACS restores neural processing in impaired networks and improves dexterity following stroke. More broadly, these results demonstrate approaches to optimize stimulation to target neural dynamics.

电刺激是一种很有前途的调节大脑网络的工具。然而，尚不清楚刺激如何与行为背后的神经模式相互作用。具体来说，对正在进行的神经动力学状态不敏感的外部刺激如何可靠地增强神经处理并改善功能？在这里，我们测试了从中风中恢复的非人类灵长类动物的低频硬膜外交流电刺激 (ACS) 如何与病灶周围皮层中的任务相关活动相互作用并影响抓握。我们发现 ACS 增加了与任务相关的合奏中的共烧并提高了灵活性。使用神经网络模型，我们发现模拟的 ACS 驱动了整体共烧，并通过连接受损的网络部分增强了神经活动的传播，提出了一种将增加的共射与提高的灵活性联系起来的机制。总之，我们的结果表明 ACS 可恢复受损网络中的神经处理并提高中风后的灵活性。更广泛地说，这些结果展示了优化目标神经动力学刺激的方法。