Fig. 2: Altered safety distance following footshock is mildly expressed in the neural activity of the general population of escape related SC neurons.

a Top: Schematic depiction of the optrode design and placement unilaterally in the SC. Bottom: Anatomical target schemes for all animals included in the experiment. X’s mark histologically confirmed most ventral position of the implant, recording electrodes spread in a brush-like form up to 1 mm below the X. b Diagram representing the distribution of the number of acceleration responsive units with respect to whether they respond to PE, RE, both or neither. c Histogram of neural response initiation time (s) in relation to acceleration onset (at time 0) for all acceleration-responsive units recorded in the SC. d Averaged neural response – red (z-score of firing rate, right Y-axis) and averaged velocity – blue (cm/s, left Y-axis) around acceleration onset (at time 0, X-axis). Lines represent the overall average of the corresponding measure with shaded ±SEM. e Left: In pooled acceleration-responsive units, neural response initiation times (ms) relative to acceleration onset undergoes a shift afore in distribution 21 days following footshock. Kruskal-Wallis with Dunn’s (n = 443 pre-shock; n = 362 on 7th-day; n = 310 on the 21st-day; Pre-shock vs. 7th-day p = 0.067; Pre-shock vs. 21st-day p < 0.001). Right: No change in distance (cm) from the beetle at response initiation time is observed. One-way ANOVA (n = 370 pre-shock; n = 279 on 7th-day; n = 283 on the 21st-day, p = 0.984). f PE responsive units – left: Spike initiation times (ms) relative to escape onset undergoes a shift afore in distribution. Kruskal-Wallis with Dunn’s (n = 333 pre-shock; n = 272 on 7th-day; n = 259 on the 21st-day; Pre-shock vs. 7th-day p = 0.067; Pre-shock vs. 21st-day p < 0.001). Right: An increase in distance (cm) from beetle corresponding to response initiation time 21 days following footshock. One-Way ANOVA with dunnet’s (n = 237 pre-shock; n = 203 on 7th-day; n = 220 on the 21st-day, P-S vs. 21–p = 0.016). g RE responsive units – left: no change in Spike initiation times (ms) relative to escape onset. Kruskal-Wallis (n = 250 pre-shock; n = 202 on 7th-day; n = 177 on the 21st-day; p = 0.107). Right: no change in distance at neural response initiation time. One-way ANOVA (n = 174 pre-shock; n = 123 on 7th-day; n = 128 on the 21st-day, p = 0.260). In each plot, bars represent means with error bars showing ±SEM. In violin graphs, the bold midlines represent medians with IQR in regular lines above and below them. Asterisks indicate significant comparisons (*p < .05; ***p < .001). Source data are provided as a Source Data file.