Figure 6: Lateral and axial stability during two-photon imaging.

(A) Median images of the hippocampal CA1 stratum oriens area where GCaMP6f was expressed in a VIP interneuron without (left) and with (right) motion correction processing (scale bar, 20 μm). (B) Representative traces of motion related displacement (top, red) and speed (bottom, black) are plotted over a two minutes period. (C) Distribution of displacement (top, red) and speed (bottom, black) triggered by walk-run epoch initiation (n = 52 events, 7 movies) are plotted where line and filled area represent respectively median and interquartile range over an 8 seconds period. (D) Quantification of lateral motion across most stable (blue) and walk-run (red) groups (n = 7 movies, **P < 0.01, Wilcoxon test. Data analysis (E) Representative median image of GCaMP6f expressed in VIP-positive boutons (top, white arrowheads, scale bar: 10 μm). Cropped heat maps represent stability probability maps during more stable periods (middle) or walk-run epochs (bottom) for VIP-positive terminals shown on top. (F) Representative distribution of the stability profile (median ± interquartile range, n = 5 terminals) during stable periods (blue, top) and walk-run epochs (red, bottom). Black dashed lines indicate the spatial reshuffling median level. (G) Fluorescence signal over time of a single VIP bouton, heat map shows speed magnitude. (H) Box plots showing the distribution of the maximal amplitude of the normalized stability probability from more stable period (blue) or walk-run epochs (red) (n = 10 terminals, 3 movies, P > 0.1, Wilcoxon signed rank test). (I) Box plots showing the distribution of measured diameter of stable structure above chance level from more stable period (blue) or walk-run epochs (red) (n = 10 terminals, 3 movies, Wilcoxon signed rank test, P > 0.1).