Dynamical processing of orientation precision in the primary visual cortex

Abstract

In our daily visual environment, the primary visual cortex (V1) detects oriented features from a large variety of orientation distributions. The precision of these distributions is fluctuating from one part of the visual scenery to another, and it remains unclear how V1 can account for this range of input configurations in order to achieve robust orientation recognition performances. To answer this question, we used natural-like stimuli and characterised the responses of V1 neurons to quantified variations of orientation precision. Generally, decrements of orientation precision correlated with decreased single neuron tuning, but thirty percent of the recorded neurons remained robustly tuned to imprecise inputs. The existence of these resilient neurons, which could be explained by a model of recurrent cortical inhibition, allows to encode both the orientation and its precision, improving the robustness of the overall population response in V1. Altogether, our results support the notion that the processing of orientation involves precision-specific neurons and slow recurrent dynamics, which possibly constitutes an experimental signature of predictive processes occurring in V1.