Projection-Specific Visual Feature Encoding by Layer 5 Cortical Subnetworks

• Projection targets define non-overlapping cell populations in L5 of mouse V1
• Corticotectal neurons are most broadly tuned for orientation and spatial frequency
• Corticostriatal and corticocortical neurons form correlated subnetworks in L5

SummaryPrimary neocortical sensory areas act as central hubs, distributing afferent information to numerous cortical and subcortical structures. However, it remains unclear whether each downstream target receives a distinct version of sensory information. We used in vivo calcium imaging combined with retrograde tracing to monitor visual response properties of three distinct subpopulations of projection neurons in primary visual cortex. Although there is overlap across the groups, on average, corticotectal (CT) cells exhibit lower contrast thresholds and broader tuning for orientation and spatial frequency in comparison to corticostriatal (CS) cells, whereas corticocortical (CC) cells have intermediate properties. Noise correlational analyses support the hypothesis that CT cells integrate information across diverse layer 5 populations, whereas CS and CC cells form more selectively interconnected groups. Overall, our findings demonstrate the existence of functional subnetworks within layer 5 that may differentially route visual information to behaviorally relevant downstream targets.

Graphical AbstractFigure optionsDownload as PowerPoint slide