Fig. 2: Inhibiting NI NMB neurons suppresses locomotion, arousal, and theta power.

a Experimental schematic for inhibiting NI NMB neurons and recording hippocampal LFP in head-fixed mice. b A blue laser pulse (5 s) abolished action potential firing elicited by current injection into a GtACR1-expressing neuron in the NI (n = 7 cells tested). c Raw traces showing the effect of optogenetic inhibition (blue bar) of NI NMB neurons on locomotion, arousal, and theta rhythms. d Locomotor speed aligned to laser onset. e Bar plot showing the inhibition effects on locomotor speed (n = 6 mice for all groups). f, g The effect of optogenetic inhibition on the pupil diameter across time (f) and summary data (g). h, i Grand mean of hippocampal LFP spectrograms aligned to laser onset (h) and summary data of optogenetic inhibition on theta power normalized to the sum of 0.1–12 Hz power (i). j, k Schematic (j) and time line (k) illustrating the food-chasing task, in which a mouse chased after a moving food tray to retrieve food pellets. In the third behavioral session we optogenetically inhibited NI neurons (k). l, m Optogenetic inhibition of NI neurons suppressed the chasing speed (l) and aborted the success rate of reaching the moving food tray (m). Shaded areas (d, f) and error bars (e, g, i, l, m) indicate SEM. *P < 0.05, **P < 0.01, ***P < 0.001; unpaired t test; see Supplementary Table 1 for detailed statistical analysis. Source data are provided as a Source Data file.