The generative and receptive modes of sensation in the rat whisker system Mathew Diamond (SISSA, Trieste)
Through the 1980’s and 1990’s, the elegant pathway from the whiskers to the sensory cortex proved a fruitful platform for the study of functional circuits in anesthetized animals. Only in the last 10 years have the tactile capacities of behaving rats been explored under controlled conditions; a small set of studies has combined neurophysiology with behavior. In this meeting we will argue that rats can switch between two modes of operation of the whisker sensory system: (1) generative mode and (2) receptive mode. In the generative mode, the rat moves its whiskers forward and backward to actively seek contact with objects and to palpate the object after initial contact. Discrimination of texture is one condition in which rats generate neuronal sensory representations through their own whisker motion. The sensory system must integrate “knowledge” of motor output in order to correctly interpret incoming signals. In the receptive mode, rats immobilize their whiskers to optimize the collection of signals from an object that is moving by its own power. We will present behavioral and physiological results under the two modes of operation.