Academy of Medical Engineering and Translation Medicine, Tianjin University, Tianjin 300072, China.
College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China.
Cereb Cortex. 2023 Oct 14;33(21):10723-10735. doi: 10.1093/cercor/bhad306.
Based on acoustoelectric effect, acoustoelectric brain imaging has been proposed, which is a high spatiotemporal resolution neural imaging method. At the focal spot, brain electrical activity is encoded by focused ultrasound, and corresponding high-frequency acoustoelectric signal is generated. Previous studies have revealed that acoustoelectric signal can also be detected in other non-focal brain regions. However, the processing mechanism of acoustoelectric signal between different brain regions remains sparse. Here, with acoustoelectric signal generated in the left primary visual cortex, we investigated the spatial distribution characteristics and temporal propagation characteristics of acoustoelectric signal in the transmission. We observed a strongest transmission strength within the frontal lobe, and the global temporal statistics indicated that the frontal lobe features in acoustoelectric signal transmission. Then, cross-frequency phase-amplitude coupling was used to investigate the coordinated activity in the AE signal band range between frontal and occipital lobes. The results showed that intra-structural cross-frequency coupling and cross-structural coupling co-occurred between these two lobes, and, accordingly, high-frequency brain activity in the frontal lobe was effectively coordinated by distant occipital lobe. This study revealed the frontooccipital long-range interaction mechanism of acoustoelectric signal, which is the foundation of improving the performance of acoustoelectric brain imaging.
基于电声效应，提出了电声脑成像，这是一种高时空分辨率的神经成像方法。在焦点处，大脑电活动被聚焦超声编码，并产生相应的高频电声信号。先前的研究表明，电声信号也可以在其他非焦点脑区检测到。然而，不同脑区之间电声信号的处理机制仍很稀疏。在这里，我们利用左初级视觉皮层产生的电声信号，研究了电声信号在传输中的空间分布特征和时间传播特征。我们观察到在额叶内具有最强的传输强度，全局时间统计表明，额叶在电声信号传输中具有特征。然后，使用交叉频率相位-幅度耦合来研究额叶和枕叶之间的电声信号频带范围内的结构内和结构间的协调活动。结果表明，这两个脑区之间存在结构内和结构间的交叉频率耦合，并且，相应地，额叶中的高频脑活动通过远距离的枕叶得到有效协调。本研究揭示了电声信号的额枕长程相互作用机制，这是提高电声脑成像性能的基础。
