Extended Data Fig. 6: Assessing the long-term single-unit recording stability using tetrode-like mesh electronics.
From: Tracking neural activity from the same cells during the entire adult life of mice
a, ISI distribution of 18 single neurons over the 7-month recording from a representative head-fixed, awake mouse. b, L-ratio (0.006 ± 0.006, mean ± s.d., n = 18 electrode arrays) and Silhouette score (0.84 ± 0.06, mean ± s.d., n = 18 electrode arrays) showing the clustering quality for the sorted single-unit action spikes over time. c-g, Firing rate (c), signal-to-noise ratio (SNR, red in e), amplitude (blue in e), peak-trough ratio (PT ratio, red in f), duration (blue in f), repolarization slope (red in g), and recovery slope (blue in g) of all the single-unit spikes as a function of time. Schematic (d) showing features extracted from the single-unit action potential waveform used for the analysis in e-g. Data represented as mean ± s.d., n = 92 neurons from 5 mice. Individual data points are overlaid. h, Single-neuron waveform centroids across a 7-month interval from a representative mouse. The centroid for each single unit was isolated on month 5 (blue circles) and months 6, 8, and 10 (red circles, rows 1-3, respectively). Grey circles indicate the positions of the mesh electrodes. i, Average displacement of single-neuron centroids from 5 mice between month 5 (blue circle, defined at origin) and months 6, 8, and 10 (red circles, rows 1-3, respectively). Grey contours indicate quintile boundaries of the distribution of centroid position displacement for the population (month 5 versus 6, n = 97 single units; month 5 versus 8, n = 96 single units; month 5 versus 10, n = 94 single units). j, Left, the cumulative distribution of within-unit centroid displacement (red) between month 5 and months 6, 8, and 10 (rows 1–3, respectively) and across-unit centroid displacement within a day (black) for 5 independent mice. Average on month 5 versus 6, within-unit = 2.86 μm (Q1 = 1.53 μm, Q3 = 3.76 μm), across-unit = 24.59 μm (Q1 = 17.46 μm, Q3 = 31.69μm); month 5 versus 8, within-unit = 2.35 μm (Q1 = 1.09 μm, Q3 = 3.17 μm), across-unit = 24.59 μm (Q1 = 17.66 μm, Q3 = 32.35 μm); month 5 versus 10, within-unit = 2.57 μm (Q1 = 1.22 μm, Q3 = 3.26 μm), across-unit = 24.68 μm (Q1 = 17.37 μm, Q3 = 32.53 μm). Two-sided Wilcoxon rank-sum test, P values are indicated in the graphs, n same as i. Inset at right, zoomed-in view to the 0 to 10 μm on x-axis.
