Fig. 3: Optogenetic stimulation of TeA–dPAG circuit triggers firing and running.
From: A shared speed encoding model for running and backing away behaviours in segregated neural circuits
a–e Experimental schematic: virus injection, opto-activation, recording sites and channelrhodopsin-2 (ChR2) expression in TeA–dPAG circuit. BL blue light. f–j Representative example showing behavioural responses vary with stimulation frequency (St. Fre.). Two control groups were included: control-1(injected with EYFP-only virus variants (a, c–e)) to exclude the effects of viral diffusion; control-2 (no virus, blue light only) to control for visual stimulus effects. k–o Running speed plotted against St. Fre. (every 10 trials) with fits. n: number of experimental animals. p, q Values of vm (p) and τ of running stimulation (τs) (q) obtained from (k–o). * P < 0.05, ** P < 0.01, *** P < 0.001, one-way ANOVA with the Bonferroni post hoc correction. r Firing rates following stimulation at different frequencies for TeA CaMKIIα neurons (a), TeAdPAG fibres (b), and TeAdPAG neurons (e). Thick lines: average; values: fit slope. s In vivo loose-patch recordings from a TeA CaMKIIα neuron expressing ChR2 (ChR2+, top panel) (a) and a dPAG neuron not expressing ChR2 (ChR2−) (TeA fibredPAG) (middle panel) (b). Light pulse duration: 10 ms. Bottom: latency from photoactivation onset to the generation of neuronal action potentials. t Running latency vs. St. Fre. (every 10 trials). u Running latency vs. running speed. v Normalized running speed–firing rate curves for TeA CaMKIIα neurons (a), TeAdPAG fibres (b), and TeAdPAG neurons (e) with fitted curves (n = 6, 5, 5 cells from 6, 5, 5 mice); dashed lines were obtained from (2r). Data are presented as mean ± SD. Supplementary Data 1 for detailed statistics. Source data are provided as a Source Data file.
