Format

Send to

Choose Destination
Nat Neurosci. 2016 Aug;19(8):1003-9. doi: 10.1038/nn.4323. Epub 2016 Jun 13.

Orientation selectivity and the functional clustering of synaptic inputs in primary visual cortex.

Author information

1
Max Planck Florida Institute for Neuroscience, Jupiter, Florida, USA.
2
Integrative Biology and Neuroscience Graduate Program, Florida Atlantic University, Jupiter, Florida, USA.

Abstract

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.

Comment in

PMID:
27294510
PMCID:
PMC5240628
DOI:
10.1038/nn.4323
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center