Long-term near-continuous recording with Neuropixels probes in healthy and epileptic rats

Neuropixels probes have become a crucial tool for high-density electrophysiological recordings. Although most research involving these probes is in acute preparations, some scientific inquiries require long-term recordings in freely moving animals. Recent reports have presented prosthesis designs for chronic recordings, but some of them do not allow for probe recovery, which is desirable given their cost. Others appear to be fragile, as these articles describe numerous broken implants. Objective. This fragility presents a challenge for recordings in rats, particularly in epilepsy models where strong mechanical stress impinges upon the prosthesis. To overcome these limitations, we sought to develop a new prosthesis for long-term electrophysiological recordings in healthy and epileptic rats. Approach. We present a new prosthesis specifically designed to protect the probes from strong shocks and enable the safe retrieval of probes after experiments. Main results. This prosthesis was successfully used to record from healthy and epileptic rats for up to three weeks almost continuously. Overall, 10 out of 11 probes could be successfully retrieved with a retrieval and reuse success rate of 91%. Significance. Our design and protocol significantly improved previously described probe recycling performances and prove usage on epileptic rats.