Fig. 1
Population activities of NAc D1R neurons across sleep–wake states. a Schematic of the fiber photometry setup and in vivo recording configuration. DM dichroic mirror, PMT photomultiplier tube. b Unilateral viral targeting of AAV-EF1α-DIO-GCaMP6f into the NAc and the tip of fiber optic above the NAc. Scale bar: 1 mm. Right: Viral expression of GCaMP6f and the placement of fiber-optic probe above the NAc. Scale bar: 200 μm. c The 40× confocal images from a NAc D1R neurons::GCaMP6f brain section immunostained for substance P (SP) and DAPI displaying the colocalization between GCaMP6f-positive neurons (green) and SP (red) cells. White arrowheads highlight NAc D1R neurons expressing GCaMP6f. Scale bar: 10 μm. d Representative fluorescence traces, relative EEG power, and EEG/EMG traces across spontaneous sleep–wake states. ∆F/F represents change in fluorescence from median of the entire time series. e Fluorescence (mean ± s.e.m.) during wake, NREM sleep, and REM sleep for 3 mice, the fluorescence signal is the highest during REM sleep, intermediate during wake, and the lowest during NREM sleep (n = 3 mice, 10 sessions per mouse, one-way ANOVA followed by Turkey’s post hoc test; F2,87 = 164.9, P = 2 × 10−30; P (wake–NREM) = 5 × 10−9, (wake–REM) = 3 × 10−6, (NREM–REM) = 5 × 10−9). f Fluorescence signals aligned to wake state transitions. Upper panel, individual transitions with color coded fluorescence intensity (NREM–wake, n = 141; wake to NREM, n = 204; NREM to REM, n = 78; REM to wake, n = 73). Lower panel, mean (blue trace) ± s.e.m. (gray shading) showing the average calcium transients from all the transitions. **P<0.01
