"Supersessioning": A hardware/software system for electrophysiology spanning multiple sessions in marmosets
We introduce a straightforward, robust method for recording and analyzing spiking activity over timeframes longer than a single session, with primary application to the marmoset (Callithrix jacchus). Although in theory the marmosets smooth brain allows for broad deployment of powerful tools in primate cortex, in practice marmosets do not typically engage in long experimental sessions akin to rhesus monkeys. This potentially limits their value for detailed, quantitative neurophysiological study. Here we describe chronically-implanted arrays with a 3D arrangement of electrodes yielding stable single and multi-unit responses, and an analytic method for creating "supersessions" combining that array data across multiple experiments. We could match units across different recording sessions over several weeks, demonstrating the feasibility of pooling data over sessions. This could be a key tool for extending the viability of marmosets for dissecting neural computations in primate cortex.