Figure 7.

Whisking is a signature of motor plan and behavioral state. A, Right and left turning mice plan their movement in the plus maze, and this plan is reflected in how they position their whiskers. Left turning mice protract their whiskers on the right side while moving backward, and right turning mice protract their whiskers on the left side while moving backward (mice in the semicircles show whisker position for right and left turning mice). The numbers next to the mice indicate the different behavioral epochs. At the onset of backward movement (1), whiskers are already asymmetric. As the animal continues moving backward toward the middle of the maze (2), the asymmetry in whisker position increases until the mouse exits the lane and is in the middle of the maze (3). As the mouse moved forward into a new lane, the asymmetric whisker positioning flipped (4); and then as the mouse proceeded into the lane, the asymmetry diminished (5). The trial ends when the animal is licking (6). B, Schematic of whisker position as a signature of behavioral state and movement preparation. Asymmetry in whisker position and whisker set point both reflects the distinct behavioral state of the animal. The numbers in the schematic are the behavioral states (related to the numbers used in A).