High-density single-unit human cortical recordings using the Neuropixels probe

• Published in: Neuron (Cambridge, Mass.) Mass.), 2022-08, Vol.110 (15), p.2409-2421.e3
• Main Authors: Chung, Jason E., Sellers, Kristin K., Leonard, Matthew K., Gwilliams, Laura, Xu, Duo, Dougherty, Maximilian E., Kharazia, Viktor, Metzger, Sean L., Welkenhuysen, Marleen, Dutta, Barundeb, Chang, Edward F.
• Format: Article
• Language: English
• Subjects: extracellular recording; human electrophysiology; human intraoperative recording; Neuropixels; single-unit recording
• ISSN: 0896-6273; 1097-4199
• DOI: 10.1016/j.neuron.2022.05.007

The action potential is a fundamental unit of neural computation. Even though significant advances have been made in recording large numbers of individual neurons in animal models, translation of these methodologies to humans has been limited because of clinical constraints and electrode reliability. Here, we present a reliable method for intraoperative recording of dozens of neurons in humans using the Neuropixels probe, yielding up to ∼100 simultaneously recorded single units. Most single units were active within 1 min of reaching target depth. The motion of the electrode array had a strong inverse correlation with yield, identifying a major challenge and opportunity to further increase the probe utility. Cell pairs active close in time were spatially closer in most recordings, demonstrating the power to resolve complex cortical dynamics. Altogether, this approach provides access to population single-unit activity across the depth of human neocortex at scales previously only accessible in animal models. [Display omitted] •Single-unit recordings in 8 patients, yielding 596 putative single units across 11 recordings•Units take longer to fire first spike in anesthetized versus awake participants•Negative correlation between the motion of the electrode array and single-unit yield Recent technologies have enabled simultaneous recording from large numbers of individual neurons in animal models. Here, Chung, Sellers, et al. translate this technology to record from tens to hundreds of individual neurons in humans undergoing neurosurgical procedures. They provide quantitative unit metrics to serve as a benchmark for recording quality.