Neuropixels constitute a step advance in recording technology. They have 966 sites arranged in two columns and spaced only 20 μm apart. Such dense and numerous recording sites, and the extremely low noise levels, allow superior discrimination of the spikes of individual neurons.
Their success is due to three innovations: (1) a multilayer fabrication process that allows 384 interconnects on a thin shank; (2) on-shank CMOS circuitry that allows 384 sites to be rapidly selected from a total of 966; (3) on-device processing that amplifies, digitizes, and multiplexes the signals.
Neuropixels thus constitute a self-contained recording system: the data that emerge are already digital, and can be read by a simple, inexpensive interface to a standard computer.
For more information about recent technological advances in this field and analysis of the opportunities and challenges presented by Neuropixels recordings, see this review by Steinmetz et al (Curr Op Neurobiol, 2018).