A ROBUST BRAIN IMPLANTATION METHOD FOR LONG-TERM WIRELESS ELECTROPHYSIOLOGICAL RECORDING IN FREELY BEHAVING MINIPIGS

Electrophysiological monitoring in freely moving animals is essential for understanding the relationship between neural activity and behavior. However, achieving reliable, long-term brain implantation in large animal models remains challenging due to surgical complexity, infection risk, and degradation of signal quality over time. Here, we present a robust brain implantation method that enables stable, low-noise, real-time electrophysiological recordings in freely behaving Lanyu minipigs for up to 90 days. This approach employs a precisely controlled aseptic surgical procedure, combined with customized multi-channel tungsten electrodes and a lightweight, water-resistant wireless recording headstage targeting both the hippocampus and cortex. The minimally invasive design ensures long-term implant stability while effectively preventing infection and minimizing motion-related artifacts. Consistent, high-quality neural signals were maintained throughout the 90-day recording period, with continuous monitoring sessions exceeding 8 hours without restricting natural behavior. The performance of the implantation strategy was validated through real-time electrophysiological recordings during behavioral paradigms, including open-field exploration and gait analysis. Across all experiments, recordings exhibited high signal fidelity and low artifact levels. Importantly, no signs of infection, neurological deficits, or abnormal behaviors were observed, supporting the biocompatibility and surgical reliability of the system. This brain implantation method provides a practical and reproducible solution for chronic electrophysiological studies in large animal models, enabling long-term investigation of neural dynamics during complex behaviors and supporting translational research in brain-computer interfaces and neurological therapies.