Extended Data Fig. 7: Optogenetic excitation of Area X.
From: Holistic motor control of zebra finch song syllable sequences
a) Experiment design, ChRmine expression in Area X and outline of the optic fiber track (scale bar 500 µm), and song spectrogram showing song-contingent light stimulation of Area X neurons (top: control, scalebar 200 ms; bottom: stimulated, 200 ms 532 nm light pulses, red bars, horizontal lines identify the bouts’ (black), introductory notes’ (light gray), motifs’ (dark gray) and linker syllable’s (brown) boundaries). b) Probability of motif truncation (okra), pause and continuation of the motif (green) or absence of syntactic perturbation (gray) after the light stimulation of Area X (X stimulated birds, n = 5, filled circles; empty box plots from HVC stimulation in Fig. 1e reported for comparison; two-way ANOVA testing the difference between stimulation outcome probabilities across all experimental groups, interaction F(14,46) = 57.75 P < 0.001, stimulated subpopulation F(7,23) = 1.088 P = 0.4027, Dunnett’s post-hoc pan-HVC vs. Area X, motif stop P < 0.001, pause+continuation P = 0.2842, no perturbation P < 0.001). c-f) Violin plots reporting accuracy and entropy of song segments with (gray) and without (white) stimulation for each bird (accuracy: n = 5, two-way ANOVA, testing the effect of optogenetic stimulation, interaction F(4,95) = 0.9003 P = 0.4671, CTRL vs. STIM, F(1,95) = 1.108 P = 0.2953; entropy: n = 5, two-way ANOVA, interaction F(4,95) = 6.521 P < 0.001, CTRL vs. STIM, F(1,95) = 16.50 P < 0.001; amplitude: two-way ANOVA testing the effect of optogenetic stimulation, interaction F(4,95) = 8.025 P < 0.001, CTRL vs. STIM, F(1,114) = 0.5747 P = 0.4503; goodness of pitch: two-way ANOVA, interaction F(4,95) = 9.002 P < 0.001, F(1,114) = 6.606 P = 0.0117). Brain outline in a adapted with permission from ref. 60, Wiley.
