Extended Data Fig. 4: Characterization of single-unit recording quality of mesh electronics with tetrode-like electrode arrays.
From: Tracking neural activity from the same cells during the entire adult life of mice
a, Bright-field (BF) microscopic image of representative mesh electronics with tetrode-like electrode arrays. Each mesh electronics consisted of five electrode arrays. Each array included six individually addressable electrodes for recording. b, Representative raw voltage traces showing spike signals recorded from two representative electrode arrays (orange and blue background labels, respectively) in an awake, head-fixed mouse at month 5. c, Zoomed-in view of the red arrow-highlighted region in (b). d, Representative single-unit waveforms were recorded simultaneously by multiple electrodes. Data represented as mean ± s.d. e, Inter-spike interval (ISI) distributions of representative single-unit spikes. f, Auto- and cross-correlograms (colored and black plots, respectively) of the representative single-units. g, Single-unit waveform centroids (n = 32 neurons) from a representative recording (centroid computed using spatial average across electrode positions weighted by the mean waveform amplitude at each electrode). h, Likelihood-ratio (L-ratio, 0.017 ± 0.013, mean ± s.d.) and Silhouette score (0.77 ± 0.09, mean ± s.d.) showing the clustering quality from identified neurons with multiple electrodes. n = 5 electrode arrays, and individual data points are overlaid. Box, 75% and 25% quantiles. Line, median. Whisker, the maxima/minima or to the median ± 1.5× IQR. The dashed lines are L-ratio of 0.05 (purple) and silhouette score of 0.5 (red), commonly taken as a threshold of high cluster quality. i, The probability density of refractory period violations (1.26% ± 0.93%, mean ± s.d., the refractory period violation is defined as an ISI < 1.5 ms, n = 32 neurons).
