Abstract：
The present study aimed to investigate the effectiveness of closed-loop transcranial ultrasound stimulation (closed-loop TUS) as a non-invasive, high temporal-spatial resolution method for modulating brain function to enhance memory. For this purpose, we applied closed-loop TUS to the CA1 region of the rat hippocampus for 7 consecutive days at different phases of theta cycles. Following the intervention, we evaluated memory performance through behavioral testing and recorded the neural activity. Our results indicated that closed-loop TUS applied at the peak phase of theta cycles significantly improves the memory performance in rats, as evidenced by behavioral testing. Furthermore, we observed that closed-loop TUS modifies the power and cross-frequency coupling strength of local field potentials (LFPs) during memory task, as well as modulates neuronal activity patterns and synaptic transmission, depending on phase of stimulation relative to theta rhythm. We demonstrated that closed-loop TUS can modulate neural activity and memory performance in a phase-dependent manner. Specifically, we observed that effectiveness of closed-loop TUS in regulating neural activity and memory is dependent on the timing of stimulation in relation to different theta phase. The findings implied that closed-loop TUS may have the capability to alter neural activity and memory performance in a phase-sensitive manner, and suggested that the efficacy of closed-loop TUS in modifying neural activity and memory was contingent on timing of stimulation with respect to the theta rhythm. Moreover, the improvement in memory performance after closed-loop TUS was found to be persistent.
摘要：
本研究旨在探讨闭环经颅超声刺激（闭环TUS）作为一种非侵入性，高时空分辨率的方法，用于调节大脑功能以增强记忆。为此,我们在theta周期的不同阶段连续7天对大鼠海马CA1区应用闭环TUS.干预之后,我们通过行为测试评估记忆表现,并记录神经活动.我们的结果表明，在θ周期的峰值阶段应用闭环TUS显着改善了大鼠的记忆性能，行为测试证明了这一点。此外，我们观察到闭环TUS在记忆任务期间改变了局部场电位（LFP）的功率和交叉频率耦合强度，以及调节神经元活动模式和突触传递，取决于刺激相对于θ节律的相位。我们证明了闭环TUS可以以相位依赖性方式调节神经活动和记忆性能。具体来说,我们观察到闭环TUS在调节神经活动和记忆方面的有效性取决于不同θ相的刺激时间.研究结果表明，闭环TUS可能具有以相位敏感方式改变神经活动和记忆表现的能力，并表明闭环TUS在改变神经活动和记忆方面的功效取决于刺激对theta节律的时间。此外，发现闭环TUS后内存性能的改善是持久的。
