Flexible multi-channel electrodes for acute recording in the non-human primates

Abstract Flexible electrodes have demonstrated good biocompatibility compared to rigid electrodes in relieving encapsulation and long-term recording. The structural and functional properties of the brain in non-human primates are closer to those of humans than in rodents. However, the application of flexible electrodes on non-human primates has been rarely reported. One of the challenges is the long experimental iteration of the electrodes, limited by implanting period, both pre- and post-surgery. In the present study, a flexible multi-channel electrode array for non-human primates was developed and implemented to the extracellular recording in behaving monkeys. To decrease possible risks, a guide-tube-compatible implantation solution was designed to implant electrodes into the cortex without durotomy. Furthermore, packaging and acute recording of multi-channel flexible electrodes for primates were tested ex vivo and in vivo. The results showed that the flexible electrodes and implantation method used in this study meet the needs of extracellular recording in non-human primates. Task-related neuronal activities were recorded with a high signal-to-noise ratio, providing a minimally invasive and clinically viable approach for extracellular recording.