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bioRxiv · 10.1101/120725

Context-Dependent Attractor Dynamics in Visual Cortex

Tajima, S.·Koida, K.·Tajima, C. I.·Suzuki, H.·Aihara, K.·Komatsu, H.
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Abstract

The capacity for flexible sensory-action association in animals has been related to context-dependent attractor dynamics outside the sensory cortices. Here we report a line of evidence that flexibly modulated attractor dynamics during task switching are already present in the higher visual cortex in macaque monkeys. With a nonlinear decoding approach, we can extract the particular aspect of the neural population response that reflects the task-induced emergence of bistable attractor dynamics in a neural population, which could be obscured by standard unsupervised dimensionality reductions such as PCA. The dynamical modulation selectively increases the information relevant to task demands, indicating that such modulation is beneficial for perceptual decisions. A computational model that features nonlinear recurrent interaction among neurons with a task-dependent background input replicates the key properties observed in the experimental data. These results suggest that the context-dependent attractor dynamics involving the sensory cortex can underlie flexible perceptual abilities.

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Tajima, S., Koida, K., Tajima, C. I., Suzuki, H., Aihara, K., Komatsu, H.. 2017-03-26. Context-Dependent Attractor Dynamics in Visual Cortex. https://doi.org/10.1101/120725

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