The majority of neurons in primary visual cortex are tuned for stimulus orientation, but the factors that account for the range of orientation selectivities exhibited by cortical neurons remain unclear. To address this issue, we used in vivo two-photon calcium imaging to characterize the orientation tuning and spatial arrangement of synaptic inputs to the dendritic spines of individual pyramidal neurons in layer 2/3 of ferret visual cortex. The summed synaptic input to individual neurons reliably predicted the neuron’s orientation preference, but did not account for differences in orientation selectivity among neurons. These differences reflected a robust input–output nonlinearity that could not be explained by spike threshold alone and was strongly correlated with the spatial clustering of co-tuned synaptic inputs within the dendritic field. Dendritic branches with more co-tuned synaptic clusters exhibited greater rates of local dendritic calcium events, supporting a prominent role for functional clustering of synaptic inputs in dendritic nonlinearities that shape orientation selectivity.
You may also like
Hitchhiking through the nerve cell
Getting in the Groove: Why samba makes everyone want...
Estimating the pace of change
April 26, 2022Max Planck Institute for Biological Cybernetics
Prefrontal cortex involved in conscious vision
April 26, 2022Max Planck Institute for Biological Cybernetics
Out of rhythm: Compromised precision of theta-gamma...
April 26, 2022Max Planck Institute for Human Development
Near-natural, fractal architecture promotes well-being
April 26, 2022Max Planck Institute for Biological Cybernetics