Fig. 4: SNc-projecting SC neurons encode locomotion speed.
From: The tectonigral pathway regulates appetitive locomotion in predatory hunting in mice
a Schematic diagram showing a head-fixed awake mouse walking on a cylindrical treadmill (left) and antidromic activation strategy for single-unit recording from SNc-projecting SC neurons (right). b Correlation analysis of action potentials of individual units evoked either by light pulses (Light) or by locomotion (Locomotion), confirming a segregation between antidromically identified units (red dots and traces) and unidentified units (gray dots and traces). c Raster (top) and peristimulus time histogram (PSTH, bottom) of an example putative SNc-projecting SC neurons showing a latency of ~3 ms relative to the onset of light pulses. d Smoothed PSTH (trace in black) of an example putative SNc-projecting SC neuron aligned with locomotion speed (trace in red). e, f Heat-map graphs (top) and averaged time course (bottom) of Z-scored firing rate of 18 putative SNc-projecting SC neurons aligned to the onset (e) and the offset (f) of locomotion. g Averaged (red) and individual (gray) normalized instantaneous firing rate during locomotion as a function of locomotion speed in 500 ms bins. h Distribution of recording site (black dots) in the SC. Number of units was indicated in the graphs (e–g). Data in e–g are means ± SEM (error bars).
