Behavioral strategies employed for chemotaxis have been studied across phyla, but the neural computations underlying navigational decisions remain elusive. By combining electrophysiology, quantitative behavioral analysis and computational modeling, we explore how olfactory signals experienced during free motion are processed by the olfactory system of the Drosophila larva. We create virtual sensory environments based on optogenetics to study how peripheral olfactory information is converted into elementary orientation responses. Our work aims to unravel the loop that organizes the acquisition of sensory information through active movements of the body.