Fig. 6 |. Facilitation of reflexes in awake mice.

a, Recording tail muscle EMG and evoking monosynaptic reflexes (MSR) with tail nerve stimulation (1.1xT, 0.2 Hz; T: reflex threshold) in GAD2//ChR2 mice, while activating GABAaxo neurons (PAD) with light (λ = 447 nm, 10 ms pulse, 1.5xT, 5 mW/mm²) applied through a chronically implanted window over the spinal cord. A backpack (pink plastic) was clipped to the window structure at the time of recording to hold the fibre optic cable. b-c, Effect of light pulse λ on active background EMG (Active Bkg condition in b) and the MSR evoked 60 ms later, the latter expanded in (c). MSR tested with (c, top; Active Bkg, 30% max) and without (c, bottom; Rest) background EMG. Thin black lines in (b) are individual trial examples at 10 s intervals (0.1 Hz); thick lines: averages. d, Changes in MSR with light activation of GABAaxo neurons at matched postsynaptic background (Bkg measured over 20 ms prior to MSR; lack of change in Bkg). Measured in active and resting (no Bkg) states, in ChR2+ and ChR2− mice (rest only), and during (60 ms ISI) and post PAD (200ms ISI at rest only). ISI: interstimulus interval. * significant change, two- sided paired t-tests with Bonferroni correction, P < 0.05, n = 5 mice each, with specifically no significant change in Bkg with PAD, P = 0.62 and 0.68 for active and rest, respectively. Box plots show the interquartile range (box), median (thin line), mean (thick line), 10 and 90 percentile (whiskers) and extremes (dots).