Fig. 1: Mesoscale calcium responses to motion energy in natural visual stimuli.

a Schematic of the custom epifluorescent wide-field microscope for in vivo GCaMP6s imaging. The screen depicts a retinotopic mapping stimulus, with a drifting bar moving across the visual field (azimuth mapping). b Areal maps from one session of a single example mouse. Left: surface raw fluorescence image of a 4 mm cortical window of example Emx1-GCaMP6s mouse. Middle: horizontal and vertical retinotopic maps showing preferred ___location of each pixel for azimuth (left) and elevation (right); color bars indicate degree offset from center of visual field). Right: sign map (red, positive; blue, negative), and resulting segmentation of visual cortex into V1 and HVAs. Scale bars = 1 mm. c Schematic of the natural movie stimulus. Scenes were repeated 20 times to measure reliable neural responses. d Top: map from a single experiment showing reliability across posterior cortex; visual area segmentation as in (b). Bottom: multi-trial response (20 repeats) and mean trace (±s.e.m. shaded) of a single pixel (blue square) to repeated presentation of the natural movie. Reliability is defined as the across-trial Pearson correlation coefficient (r = 0.31, see Methods). e Mean reliability map across all imaged mice (n = 19 sessions over 7 mice). Individual maps are transformed onto a common coordinate system for comparison across mice. f Extraction of the motion energy in the stimulus. Pixel-wise motion vectors were extracted from each frame of the movie, and the sum of these vectors is used as a measure of the net motion energy of each frame. g Top: map from a single experiment showing motion response across posterior cortex; visual area segmentation as in (b). Bottom: Neural response of a single pixel (red) overlaid on the motion trace (gray); pixel-wise motion energy correlation is calculated as the Pearson correlation between these two signals (r = 0.24). h Mean motion energy correlation map across all imaged mice (n = 19 sessions over 7 mice); alignment procedure same as (e). Area abbreviations: primary visual (V1), lateral medial (LM), anterolateral (AL), posterior medial (PM), laterointermediate (LI), rostrolateral (RL), and anteromedial (AM).