In vivo extracellular recordings of thalamic and cortical visual responses reveal V1 connectivity rules

The brain's connectome provides the scaffold for canonical neural computations. However, a comparison of connectivity studies in the mouse primary visual cortex (V1) reveals that the average number and strength of connections between specific neuron types can vary. Can variability in V1 connectivity measurements coexist with canonical neural computations? We developed a theory-driven approach to deduce V1 network connectivity from visual responses in mouse V1 and visual thalamus (dLGN). Our method revealed that the same recorded visual responses were captured by multiple connectivity configurations. Remarkably, the magnitude and selectivity of connectivity weights followed a specific order acrossmost of the inferred connectivity configurations. We argue that this order stems from the specific shapes of the recorded contrast response functions and contrast invariance of orientation tuning. Remarkably, despite variability across connectivity studies, connectivity weights computed from individual published connectivity reports followed the order we identified with our method, suggesting that the relations between the weights, rather than theirmagnitudes, represent a connectivity motif supporting canonical V1 computations.

Automated summary

In this study, a theory-driven approach was used to deduce V1 network connectivity from visual responses in mouse V1 and visual thalamus (dLGN). The researchers found that connectivity weights followed a specific order across different connectivity configurations, which may be related to the shape of contrast response functions and contrast invariance of orientation tuning. Furthermore, the study also revealed that despite variability across connectivity studies, connectivity weights computed from individual published connectivity reports still followed the same order.