Extended Data Fig. 5: ROIs involved in the same single cell share high intrinsic noise correlation.
(a) Schematic of intrinsic noise correlation. Suppose that there are four ROIs, with groups of two belonging to different cells (left). The response variances across trials are shared among ROIs from the same neurons (right; for example, ROI#1 and #3). (b) Left, iGABASnFR2 was expressed selectively in SACs (green). The dendritic processes of a single SAC were visualized by AlexaFluor 594 loaded through a patch pipette (magenta). Dotted gray circle, cell body of the patched cell. Right, example ROIs for GABA imaging from specified (magenta) and unspecified (green) dendritic processes. (c) A correlation matrix of the 16 ROIs in (b). ROIs on a single SAC (ROIs #1-#6) had similar noise correlation. (d) Left, comparisons of variance in response profiles between ROIs within the same groups and shuffled ROIs (49 groups, P = 1.11 \(\times\) 10-9, Wilcoxon signed-rank test). Right, response variances computed in ROIs on a single SAC (light gray; 82 pairs) and ROIs on unspecified SAC processes (dark gray; 28 pairs) in ChAT-IRES-Cre mice. Since the analysis of GABA signals was restricted to iGABASnFR2 expressed in the membrane of SACs, the difference in variance between groups was low. Two-sided Mann–Whitney-Wilcoxon test, Bonferroni correction for multiple comparisons. (e) Comparisons of noise correlation between ROIs on the same (“Same neurites”; 57 pairs, P = 0.030381, Two-sided Mann–Whitney-Wilcoxon test) and different neurites (“Different neurites”; 11 pairs) of a single SAC, ROIs on neurites of unspecified cells with unspecified preferred direction (Multiple SACs; 142 pairs, P = 1.38 \(\times\) 10-6, Two-sided Mann–Whitney-Wilcoxon test), ROIs on neurites of unspecified cells with same preferred direction (Multiple SACs, same pref. dir.; 20 pairs). 3 retinae. Different neurites of the same SAC showed lower correlation than ROIs from the same neurites, but still showed higher correlation than neurites from different SACs. (f) A map denoting heterogeneous correlations in G2, G5, G12, G19, G21, G35, G42, and G47. Gray, correlations with more than 0.25 noise correlation (noise corr.). Colored, significantly coincident connections. (g) Heatmaps indicating distribution of observed G2, G5 (delayed-ON), G12, G19, G21 (ON), and G35, G42, G47 (OFF) groups. Yellow squares, average distribution for delayed-ON, ON, and OFF groups. (h) A summary of characteristics of groups with heterogeneous connectivity. *, P < .05; *** P < .001; boxes represent 25 th–75th percentiles and median; whiskers represent 1.5 times the interquartile range.
