Figure 5.
Initiation of locomotion evoked by stimulation of glutamateric CnF neurons after chronic SCI
(A) Trajectories of full-body movement evoked upon long-train photostimulation of glutamatergic neurons of the CnF at different frequencies (n = 5 mice). Mice were tracked using a marker placed on their neck. Trajectories of all mice were centered at (x0,y0) 1 s prior to stimulation. A locomotor bout occurred if the mouse walked out of the circle (radius 10 cm) centered on the position of the body at the beginning of the stimulation.
(B) Mean and SD of locomotor speed evoked upon long trains of photostimulation of the CnF at 20 and 50 Hz. Color-coded matrices representing individual trials (100-ms bins).
(C) Vectors represent the upper body direction and the distance traveled (vector length) during the first 500 ms of photostimulation of the CnF at 50 Hz (highlighted in yellow on the timeline).
(D) Body displacement evoked by photostimulation of the CnF at 20 (34 trials) and 50 Hz (25 trials). A 10-cm displacement was considered as a full-body movement (i.e., an initiation of locomotion). All displacements occurring within the 3 s from the start of the stimulation were considered (highlighted on the timeline).
(E) Latency to initiate full-body movement (>10 cm) upon stimulation of the CnF at 20 (34 trials) and 50 Hz (21 trials; Mann-Whitney test, p = 0.001).
(F) Percentage of trials in which initiation of locomotion started within the first second of photostimulation of the CnF at 20 and 50 Hz.
(G) Locomotor score of the left ipsilesional hindlimb during spontaneous vs. stimulated locomotion of the CnF at 20Hz over time after SCI (n = 7 mice).
(H) Trajectories of full-body movement evoked upon photostimulation of glutamatergic neurons of the PPN (n = 7 mice).
(I) Mean and SD of locomotor speed evoked upon long trains of photostimulation of the PPN at 20 and 50 Hz. Color-coded matrices representing individual trials (100 ms bins).
(J) Vectors illustrate consistent upper body rotation ipsilateral to the stimulation site within a 5-cm radius; 50-Hz photostimulation of the PPN evoked consistent rapid motor movements with little displacement, considered as a postural rotation.
(K) Body displacement evoked by photostimulation of the PPN at 20 (67 trials) and 50 Hz (45 trials).
(L) Latency to initiate full-body movement (>10 cm) started after the end of the PPN photostimulation (20 Hz, 15 trials; 50 Hz, 15 trials).
(M) Percentage of trials in which initiation of locomotion started within the first second of photostimulation of the PPN at 20 and 50 Hz. See also Figure S9.