Figure 5.

Stimulation of DN/IPN or MTh_DN/IPN axon terminals triggers movement initiation

(A) Dual MTh photoactivation strategy; ChR2 expression targeted to MTh_DN/IPN, stimulation via optic fiber directly above MTh_DN/IPN (#1) or tapered fiber in CFA (#2).

(B) Full lever push probability during an auditory go cue (black) or photoactivation of MTh_DN/IPN (#1) or MTh_DN/IPN axons in CFA (#2) in the absence of a go cue (green). Colored dots, individual mice; colored circles, mean ± 95% CI (cue, 1 and 2; N = 12, 12, and 6 mice, respectively).

(C) Change in subthreshold V_m ± 95% CI in a layer 5B projection neuron during the go cue (black) or photoactivation of MTh_DN/IPN (green) in the absence of a cue. Dashed line, movement initiation.

(D) Peri-movement cue-evoked and photoactivated subthreshold ΔV_m correlation during push trials (n = 7 neurons, N = 6 mice). Filled symbols, mean ± 95% CI; red line, linear fit to the data (Pearson’s r).

(E) Recording and photoactivation strategy: silicone probe recordings of deep-layer putative pyramidal cells in CFA during photoactivation of ChR2-expressing DN/IPN axon terminals in MTh_DN/IPN.

(F) Full lever push probability during an auditory go cue or photoactivation of DN/IPN axon terminals in MTh_DN/IPN in the absence of a go cue. Colored dots, individual mice; colored circles, mean ± 95% CI (N = 4 and 4 mice).

(G) Spike rasters and peri-stimulus time histograms (PSTHs) from deep-layer CFA neurons aligned to movement initiation (dashed line). Black, cue trials; green, photoactivation trials.

(H) Peri-movement cue-evoked and photoactivated Δfiring rate correlation during push trials (n = 30/47 neurons, N = 4 mice). Symbols, mean ± 95% CI; red line, linear fit to the data (Pearson’s r).