Temporal stability of stimulus representation increases along rodent visual cortical hierarchies

Cortical representations of brief, static stimuli become more invariant to identity-preserving transformations along the ventral stream. Likewise, increased invariance along the visual hierarchy should imply greater temporal persistence of temporally structured dynamic stimuli, possibly complemented by temporal broadening of neuronal receptive fields. However, such stimuli could engage adaptive and predictive processes, whose impact on neural coding dynamics is unknown. By probing the rat analog 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 grew gradually along the hierarchy. A database of recordings from mouse showed similar trends, additionally revealing dependencies on the behavioral state. Overall, these findings show that visual representations become progressively more stable along rodent visual processing hierarchies, with an important contribution provided by intrinsic processing. Understanding stability of representation in the visual system can benefit by use of non-static, naturalistic stimuli. Here the authors examine stability of neural representations along the rat ventral stream while viewing naturalistic and synthetic movies.

Automated summary

Cortical representations of brief, static stimuli become more invariant along the ventral stream in terms of identity-preserving transformations. Deeper areas in the visual hierarchy encode visual information more persistently for temporally structured dynamic stimuli. The impact of intrinsic dynamics on stability of stimulus representations grows gradually along the hierarchy.