PROJECT SUMMARY Chronic multichannel electrophysiology is a critical tool for examining how behavior arises from the complex interconnected activity of the brain. The goal of this project is to provide a commercial ecosystem for multi-electrode array (MEA) manufacturers to scale their products to many more electrodes than they currently offer. By commercializing a compact 512-channel integrated circuit—the EChip—we will offer a path for MEA manufacturers to integrate electronics directly onto their arrays, thereby sidestepping the need for bulky connectors or electronics. We aim to enable the availability of diverse types of electrodes, all with increased channel counts, to satisfy the diverse needs of experimenters. Furthermore, by developing versatile electronics and powerful software to interface with the EChips, the EChip-enabled MEAs will be usable in diverse behavioral paradigms and species.