Recent advances and challenges in autonomous wireless implantable neurologgers for animal studies: Neural recording, power supply, and data transmission technologies

Wireless implantable neurologgers are emerging as miniature autonomous systems for long-term, untethered neural recording in animal studies. However, the development of wireless systems remains constrained by critical engineering bottlenecks, including neural recording, power supply, and data transmission. This review first systematically summarizes representative commercial neurologgers and state-of-the-art research advances. Then, recent progress in the three engineering areas is reviewed, covering high-performance electrode technologies, efficient wireless power transfer strategies, and advanced communication technologies. The critical trade-offs among energy efficiency, bandwidth, transmission distance, and system complexity are clearly pointed out. Furthermore, the influence of diverse application environments on the system-level design and real-world practicability of neurologgers is analyzed from a new perspective. Finally, the technical challenges and the future directions are discussed to guide the development of fully autonomous wireless implantable neural recording systems for animal studies.