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bioRxiv · 10.1101/2021.05.23.445338

Learning orthogonalizes visual cortical population codes

Failor, S. W.·Carandini, M.·Harris, K. D.
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Abstract

Training in behavioral tasks can alter visual cortical stimulus coding, but the precise form of this plasticity is unclear. We measured orientation tuning in 4,000-neuron populations of mouse V1 before and after training on a visuomotor task. Changes to single-cell tuning curves were apparently complex, including appearance of asymmetric and multi-peaked tuning curves. Nevertheless, these changes reflected a simple mathematical transformation of population activity, suppressing responses to motor-associated stimuli specifically in cells responding at intermediate levels. The strength of the transformation varied across trials, suggesting a dynamic circuit mechanism rather than static synaptic plasticity. This transformation resulted in sparsening and orthogonalization of population codes for motor-associated stimuli. Training did not improve the performance of an optimal stimulus decoder, which was already perfect even for naive codes, but the resulting orthogonalization improved the performance of a suboptimal decoder model with inductive bias as might be found in downstream readout circuits.

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Failor, S. W., Carandini, M., Harris, K. D.. 2021-05-23. Learning orthogonalizes visual cortical population codes. https://doi.org/10.1101/2021.05.23.445338

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