Fig. 6: Activation of FNE–IO neurons elicits directional saccadic and upper body movements.
From: Excitatory nucleo-olivary pathway shapes cerebellar outputs for motor control
a, Photoactivation of FNE–IO neurons while monitoring ipsilateral eye movements (N for nasal and T for temporal). b, Left: representative evoked saccades (gray, individual trials; black, mean ± s.e.m.). Right: polar plot indicating the directions and amplitudes of evoked saccades (n = 207 trials from nine mice). The distribution of all saccades is presented as the density colormap. Red arrow indicates the average saccade direction and amplitude. c, Evoked saccade velocity from the same mouse in b and summary of peak velocity from nine mice (right-hand panel, red dot and bars represent mean ± s.e.m.). d, Evoked saccade probabilities following increasing photoactivation intensities (n = 9, one-way ANOVA with repeated measures, P = 0.0005). Dots and bars represent mean ± s.e.m. e–i, FNE–IO neurons modulate spontaneous saccade. e, Optogenetic identification and recording of FNE–IO neurons during spontaneous saccade (Methods). Lighter traces, individual saccades; darker traces, mean ± s.e.m. f, Example neurons recorded during spontaneous saccade (see saccade traces in e), showing facilitation and suppression in response to nasal saccade. g, Fraction of neuron modulation in response to nasal saccade (n = 22 neurons from four mice). h, Trial-by-trial correlation between neuron activity and saccade amplitude from an example recording. Trials in the heatmaps are sorted based on the saccade amplitudes. Right: scatter plot of all trials and curve fitting (linear regression model, P = 1.1 × 10−7) from the same recording. i, Summary for all FNE–IO neurons that show significant activity-saccade amplitude correlation (n = 10). j, Left: overlay of two snapshots of a freely moving mouse, illustrating the body postures before (black) and after (red) 250-ms photoactivation. Right: serial plots of hip-chest-neck-head positions over time, illustrating movement trajectory before (black), during (red) and after (turquoise) photoactivation. k, The corresponding displacement and velocity for j. l, Summary of peak velocities and turning angles of photoactivated movements from nine mice. Red dot and bars represent mean ± s.e.m.; box-whisker plots indicate the median, interpreted quartiles and range. m, Turning angles positively correlate with the photoactivation intensities (n = 9 mice, one-way ANOVA with repeated measures, P = 0.0001). Dots and bars represent mean ± s.e.m.
