Neuronal firing rate diversity lowers the dimension of population covariability

Tian, G. J.; Zhu, O.; Shirhatti, V.; Greenspon, C.; Downey, J. E.; Freedman, D. J.; Doiron, B.

doi:10.1101/2024.08.30.610535

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bioRxiv · 10.1101/2024.08.30.610535

Neuronal firing rate diversity lowers the dimension of population covariability

Tian, G. J.·Zhu, O.·Shirhatti, V.·Greenspon, C.·Downey, J. E.·Freedman, D. J.·Doiron, B.

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Abstract

Neuronal responses are very diverse, with specific stimuli or behaviors eliciting a range of activity across a neuronal population. These responses also show large and correlated trial-to-trial fluctuations that occupy a low-dimensional region in activity space. We link these two aspects of neuronal response in both feedforward and recurrent circuit models and derive the following relation: the more diverse the firing rates of neurons in a population, the lower the effective dimension of their trial-to-trial covariability. We test our prediction using simultaneously recorded neuronal populations from numerous brain areas in mice, non-human primates, and in the motor cortex of human participants. Finally, we show how diverse neural codes lead to better stimulus discrimination, and that when the brain is in a heightened state of processing responses are more diverse and have lower-dimensional fluctuations. In sum, we present an organizing principle of population response that is widely observed across the nervous system and acts to synergistically improve population representation.

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Tian, G. J., Zhu, O., Shirhatti, V., Greenspon, C., Downey, J. E., Freedman, D. J., Doiron, B.. 2024-09-01. Neuronal firing rate diversity lowers the dimension of population covariability. https://doi.org/10.1101/2024.08.30.610535

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