Intrinsic dynamics enhance temporal stability of stimulus representation along rodent visual cortical hierarchies

Abstract

Along the ventral stream, cortical representations of brief, static stimuli become gradually more invariant to identity-preserving transformations. In the presence of long, temporally structured dynamic stimuli, higher invariance should imply temporally persistent representations at the top of this functional hierarchy. However, such stimuli could engage adaptive and predictive processes, whose impact on neural coding dynamics is unknown. By probing the rat analogue of the ventral stream with movies, we uncovered a hierarchy of temporal scales, with deeper areas encoding visual information more persistently. Furthermore, the impact of intrinsic dynamics on the stability of stimulus representations gradually grew along the hierarchy. Analysis of a large dataset of recordings from the mouse visual hierarchy yielded similar trends, revealing also their dependence on the behavioral state of the animal. Overall, these findings show that visual representations become progressively more stable along rodent visual processing hierarchies, with an important contribution provided by intrinsic processing.