Researchers catch rats' twitchy whiskers in action

This frame from a time-lapse movie shows multiple traces (red) of a single rat whisker, captured at 3,200 frames per second, as it moves from left to right across a rough surface and then a smoother one. (For clarity, only every 3rd trace is shown, or about one per millisecond). Clusters and gaps of the traces correspond to this whisker's rapid sticking and slipping movements during ~175 milliseconds of surface contact. The lower end of the whisker trace corresponds to the rat's face, which moves closer as it encounters a change from rough to smooth texture. Image courtesy / Jason Ritt, McGovern Institute for Brain Research at MIT