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bioRxiv · 10.1101/251314

Challenging the point neuron dogma: FS basket cells as 2-stage nonlinear integrators

Tzilivaki, A.·Poirazi, P.
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Abstract

Interneurons are critical for the proper functioning of neural circuits and are typically considered to act as linear point neurons. However, exciting new findings reveal complex, sub- and/or supralinear computations in the dendrites of various interneuron types. These findings challenge the point neuron dogma and call for a new theory of interneuron arithmetic. Using detailed, biophysically constrained models, we predict that dendrites of FS basket cells in both the hippocampus and mPFC come in two flavors: supralinear, supporting local sodium spikes within large-volume branches and sublinear, in small-volume branches. Synaptic activation of varying sets of these dendrites leads to somatic firing variability that cannot be explained by the point neuron reduction. Instead, a 2-stage Artificial Neural Network (ANN), with both sub- and supralinear hidden nodes, captures the variance. We propose that FS basket cells have substantially expanded computational capabilities sub-served by their non-linear dendrites and act as a 2-layer ANN.

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Tzilivaki, A., Poirazi, P.. 2018-01-22. Challenging the point neuron dogma: FS basket cells as 2-stage nonlinear integrators. https://doi.org/10.1101/251314

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