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bioRxiv · 10.1101/2024.11.14.623565

A vector calculus for neural computation in the cerebellum

Fakharian, M. A.·Shoup, A.·Hage, P.·Elseweifi, H.·Shadmehr, R.
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Abstract

Null space theory predicts that a neuron will often generate spikes not to produce behavior, but to prevent another neurons impact on behavior. Here, we present a direct test of this theory in the brain. In the marmoset cerebellum, spike-triggered averaging identified a vector for each Purkinje cell (P-cell) along which its spikes displaced the eyes. Two spikes in two different P-cells produced superposition of their vectors. In the resulting population activity, the spikes were canceled if their contributions were perpendicular to the intended movement. Mossy fibers provided a copy of the motor commands and the sensory goal of the movement. Molecular layer interneurons transformed these inputs so that the P-cell population predicted when the movement had reached the goal and should be stopped.

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Fakharian, M. A., Shoup, A., Hage, P., Elseweifi, H., Shadmehr, R.. 2024-11-14. A vector calculus for neural computation in the cerebellum. https://doi.org/10.1101/2024.11.14.623565

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