Colins A, Loft M, Petersen R

Sensory adaptation is a ubiquitous phenomenon, observed across species and sensory modalities. Adaptation has been extensively studied in anaesthetised animals. However, tactile inputs are strongly shaped by the animal’s behaviour. It is not understood how adaptation changes the representation of sensory signals in awake, behaving animals. This work aims to address this question in the somatosensory cortex in behaving mice. For this, we performed electrophysiological recordings and simultaneous 3D imaging of the whiskers during a task where mice explore an object using their whiskers. This enabled us to measure both neural activity in barrel cortex and the sensory input from the whiskers. First, we found that neurons responded more to the first whisker-object contact on a trial than to later ones. Additionally, we found that both, the strength of touches and neural sensitivity to the strength of the touches decreased over time. These results suggest that both behavioural and neural adaptations occur during active sensation.