A Wireless Integrated EEG–fNIRS System for Brain Function Monitoring

Electroencephalography (EEG) and functional near infrared spectroscopy (fNIRS) have emerged as continuous monitoring techniques for neural cluster electrical activity and local cerebral hemodynamic activity, playing a crucial role in both basic scientific research and clinical applications. However, the progress of many neuroscience studies is hindered by limitations in instrument size, portability, synchronous acquisition, and mobility. To overcome these limitations, this paper proposes an integrated system comprising 112 fNIRS channels and 16 EEG channels. The characteristic of this system is its support for measurements under mobile conditions, and the scalable design of the sensor cap allows for flexible configuration of EEG and fNIRS sensors in different experiments. A corresponding upper computer software was developed to monitor brain activity in real time. Noise and drift tests demonstrate that the instrument we designed meets the requirements for physiological signal acquisition. In visual evoked experiments, the local hemodynamic changes and visual evoked potentials of the subjects show good consistency with the experimental results reported in the literature, indicating that the proposed EEG-fNIRS acquisition system can simultaneously monitor both brain electrical activity and hemodynamic changes.