Allen Institute Openscope - Illusion project

Much of sensory neuroscience has focused on how the brain faithfully represents sensory information. However, sensory information is often incomplete and ambiguous. Hence, the brain must rely on an internal model of the sensory world to infer a coherent percept. Illusions reveal rational mistakes in perceptual inference, yielding unique insights into the brain’s internal model. Here, we utilized illusory contours (ICs) to study the microcircuit mechanisms underlying the perceptual inference of an edge. Evidence for IC perception has been shown in multiple species, including mice. Neural correlates of IC perception have also been identified, i.e., neurons that respond to ICs with the same receptive field and feature selectivity (e.g., orientation tuning) as for real edges, despite the lack of feedforward sensory drive. Our goal was to investigate how neocortical microcircuits give rise to illusory responses in IC encoders. In addition, we aimed to investigate whether the microcircuit implementation of IC encoding is common across the visual cortex hierarchy.