Figure 1. Two-Photon Microscopy in Cerebellar Cortex of Behaving Mice.

(A) Two-photon microscopy in awake, head-restrained mice using an exercise ball. Mouse locomotion was tracked by an optical encoder on the ball, which provided a sensitive, quantitative, and repeatable readout of running onset/offset, speed and direction. In addition, mouse behavior was recorded on video (Supplemental Data).

(B) Areas of lobules V and VI of the cerebellar vermis examined in this study by Ca²⁺-imaging (pink). Scale bar: 1 mm.

(C) Probability densities of image displacements in dorso-ventral, z (blue), medio-lateral, x (green), and rostro-caudal, y (red), dimensions from a set of 7 example experiments. Insets: Colored traces show x (green) and y (red) image displacements (left inset), or x (green) and z (blue) image displacements (right inset), during two examples of mouse locomotion (black trace). x and y displacements were corrected by image registration prior to data analysis. Scale bars: Upper, 50 mm/s; Lower, 10 s and 5 μm.