Predictive whisker kinematics reveal context-dependent sensorimotor strategies

by Avner Wallach, David Deutsch, Tess Baker Oram, Ehud Ahissar Animals actively move their sensory organs in order to acquire sensory information. Some rodents, such as mice and rats, employ cyclic scanning motions of their facial whiskers to explore their proximal surrounding, a behavior known as whisking. Here, we investigated the contingency of whisking ki nematics on the animal’s behavioral context that arises from both internal processes (attention and expectations) and external constraints (available sensory and motor degrees of freedom). We recorded rat whisking at high temporal resolution in 2 experimental contexts—freely moving or head-fixed —and 2 spatial sensory configurations—a single row or 3 caudal whiskers on each side of the snout. We found that rapid sensorimotor twitches, called pumps, occurring during free-air whisking carry information about the rat’s upcoming exploratory direction, as demonstrated by the ability of the se pumps to predict consequent head and body locomotion. Specifically, pump behavior during both voluntary motionlessness and imposed head fixation exposed a backward redistribution of sensorimotor exploratory resources. Further, head-fixed rats employed a wide range of whisking profiles to compensa te for the loss of head- and body-motor degrees of freedom. Finally, changing the number of intact vibrissae available to a rat resulted in an alteration of whisking strategy consistent with the rat actively reallocating its remaining...
Source: PLoS Biology: Archived Table of Contents - Category: Biology Authors: Source Type: research