Visual physiology of the layer 4 cortical circuit in silico

Anton Arkhipov, Nathan W. Gouwens, Yazan N. Billeh, Sergey L. Gratiy, Ramakrishnan Iyer, Ziqiang Wei, Zihao Xu, Reza Abbasi-Asl, Jim Berg, Michael A. Buice, Nicholas Cain, Nuno daCosta, Saskia C. J. De Vries, Daniel Denman, Severine Durand, David Feng, Tim Jarsky, Jérôme A. Lecoq, Brian Lee, Lu Li et al. (10 additional authors not shown)

Abstract: Author summary How can we capture the incredible complexity of brain circuits in quantitative models, and what can such models teach us about mechanisms underlying brain activity? To answer these questions, we set out to build extensive, bio-realistic models of brain circuitry by employing systematic datasets on brain structure and function. Here we report the first modeling results of this project, focusing on the layer 4 of the primary visual cortex (V1) of the mouse. Our simulations reproduced a variety of experimental observations in response to a large battery of visual stimuli. The results elucidated circuit mechanisms determining patters of neuronal activity in layer 4 –in particular, the roles of feedforward thalamic inputs and specific patterns of intracortical connectivity in producing tuning of neuronal responses to the orientation of motion. Simplification of neuronal models led to specific deficiencies in reproducing experimental data, giving insights into how biological details contribute to various aspects of brain activity. To enable future development of more sophisticated models, we make the software code, the model, and simulation results publicly available.