Functional limits of CMOS electrophysiology probes. Are we there yet?

The use of dense, high yield electrophysiology probes has experienced a remarkable growth since the initial development of devices like Neuroprobes and later on Neuropixels. We have developed the datasets in this project to try and answer whether even higher densities and electrode counts in these probes can further enhance our understanding of complex naturalistic behaviour and whether such advancements might affect issues like implant related behavioural restrictions. To try and answer these questions we have used a novel, complementary metal-oxide-semiconductor (CMOS) scanning probe which advances the state of the art in electrode density and concurrent measuring electrode count. It has double the density of the Neuropixels probe and records simultaneously from 3 times the Neuropixels’ electrodes (1344), thus targeting multiple brain regions but without restricting the free movement of the animals (single tether device). This was the outcome of the European research project NeuroSeeker. The data sets presented here come from the use of this probe in a large arena, freely moving, foraging experiment.