Long-range neural coherence encodes stimulus information in primate visual cortex

In the primary visual cortex, neurons with similar receptive field properties are bound together through widespread networks of horizontal connections that span orientation columns. How connectivity across the cortical surface relates to stimulus information is not fully understood. We recorded spiking activity and the local field potential (LFP) from the primary visual cortex of marmoset monkeys and examined how connectivity between distant orientation columns affect the encoding of visual orientation. Regardless of their spatial separation, recording sites with similar orientation preferences have higher coherence between spiking activity and the local field potential than sites with different preferred orientation. Using information theoretic methods, we measured the amount of stimulus information that is shared between pairs of sites. More stimulus information can be decoded from pairs with the same preferred stimulus orientation than the pairs with a different preferred orientation, and the amount of information is significantly correlated with the magnitude of beta-band spike-LFP coherence. These effects remained after controlling for firing rate differences. Our results thus show that spike-LFP synchronization in the beta-band is associated with the encoding of stimulus information within the primary visual cortex of marmoset monkeys. Significance StatementA fundamental step in processing images in the visual cortex is coordinating the neural activity across distributed populations of neurons. Here, we demonstrate that populations of neurons in the primary visual cortex of marmoset monkeys with the same stimulus orientation preference temporally coordinate their activity patterns when presented with a visual stimulus. We find maximum synchronization in the beta range depends on the similarity of orientation preference at each pair of the neural population.