Targeting defined populations of retinal ganglion cells with CMOS microelectrode arrays

Here we report on recording action potentials from a predefined neural population in the mouse retina by using a microelectronics-based high-density microelectrode array, containing 3,150 electrodes/mm2. Single-cell action potentials are recorded constantly on multiple electrodes; thus, every action potential has a unique spatial distribution, which helps to improve the spike sorting process, and enables to distinguish the activity of densely packed retinal ganglion cells. Different physiological types of retinal cells can be distinguished, based on their light response. Finally, the variety of possible electrode configurations enables to target a specific population of retinal ganglion cells for extracellular recordings.