Li Ruikai, Zhang Yixing, Fan Guangwei, Li Ziteng, Li Jun, Fan Shiyong, Lou Cunguang, Liu Xiuling
The College of Electronic Information Engineering and the Hebei Key Laboratory of Digital Medical Engineering, Hebei University, Baoding, China.
Information Center, The Affiliated Hospital of Hebei University, Baoding, China.
Front Neurosci. 2023 Jun 29;17:1193950. doi: 10.3389/fnins.2023.1193950. eCollection 2023.
The collection and process of human brain activity signals play an essential role in developing brain-computer interface (BCI) systems. A portable electroencephalogram (EEG) device has become an important tool for monitoring brain activity and diagnosing mental diseases. However, the miniaturization, portability, and scalability of EEG recorder are the current bottleneck in the research and application of BCI.
For scalp EEG and other applications, the current study designs a 32-channel EEG recorder with a sampling rate up to 30 kHz and 16-bit accuracy, which can meet both the demands of scalp and intracranial EEG signal recording. A fully integrated electrophysiology microchip RHS2116 controlled by FPGA is employed to build the EEG recorder, and the design meets the requirements of high sampling rate, high transmission rate and channel extensive.
The experimental results show that the developed EEG recorder provides a maximum 30 kHz sampling rate and 58 Mbps wireless transmission rate. The electrophysiological experiments were performed on scalp and intracranial EEG collection. An inflatable helmet with adjustable contact impedance was designed, and the pressurization can improve the SNR by approximately 4 times, the average accuracy of steady-state visual evoked potential (SSVEP) was 93.12%. Animal experiments were also performed on rats, and spike activity was captured successfully.
The designed multichannel wireless EEG collection system is simple and comfort, the helmet-EEG recorder can capture the bioelectric signals without noticeable interference, and it has high measurement performance and great potential for practical application in BCI systems.
人类大脑活动信号的采集与处理在脑机接口（BCI）系统的发展中起着至关重要的作用。便携式脑电图（EEG）设备已成为监测大脑活动和诊断精神疾病的重要工具。然而，EEG记录仪的小型化、便携性和可扩展性是当前BCI研究与应用的瓶颈。
针对头皮EEG等应用，本研究设计了一款采样率高达30kHz、精度为16位的32通道EEG记录仪，既能满足头皮EEG信号记录需求，也能满足颅内EEG信号记录需求。采用由FPGA控制的全集成电生理微芯片RHS2116构建EEG记录仪，该设计满足高采样率、高传输率和通道扩展性的要求。
实验结果表明，所开发的EEG记录仪提供了最高30kHz的采样率和58Mbps的无线传输率。在头皮和颅内EEG采集上进行了电生理实验。设计了一种接触阻抗可调的充气头盔，加压可使信噪比提高约4倍，稳态视觉诱发电位（SSVEP）的平均准确率为93.12%。还对大鼠进行了动物实验，并成功捕获了尖峰活动。
所设计的多通道无线EEG采集系统简单舒适，头盔式EEG记录仪能够在无明显干扰的情况下捕获生物电信号，具有较高的测量性能，在BCI系统中具有很大的实际应用潜力。
