Combining optogenetics with MEA, depth-resolved LFPs and assessing the scope of optogenetic network modulation

Abstract

The development of multi-electrode arrays enables researchers to record neuronal activity from several to hundreds or even thousands of neurons simultaneously. Optogenetics provides the toolbox to excite or inhibit a genetically defined subpopulation of neurons. Here, we present a detailed description of how to combine multi-electrode array (MEA) recording and optogenetics to study the role of parvalbumin positive interneurons in mouse somatosensory cortical signal processing. We also provide the tools to quantify the density of opsin-expressing cells and estimate the effective illuminated area by optogenetic stimulation, resulting in a quantification of optogenetically modulated neurons.