# Synaptic transmission as a cooperative phenomenon in confined systems

## TL;DR

This review develops a theoretical framework for synaptic transmission, modeling it as a cooperative phenomenon akin to critical phenomena in confined liquids, with insights into activation zones and nonlinear dynamics.

## Contribution

It introduces a novel theoretical approach linking synaptic transmission to critical phenomena, using nonlinear differential equations and isomorphism hypotheses.

## Key findings

- Activation zone size estimated
- Synaptic activation described as cooperative process
- Strange-attractor behavior observed in models

## Abstract

In this review paper, the theory of synaptic transmission (ST) was developed and discussed. We used the hypothesis of isomorphism between: (a) the cooperative behavior of mediators --- acetylcholine molecules (ACh) and cholinoreceptors in a synaptic cleft with binding into mediator-receptor (AChR) complexes, (b) the critical phenomena in confined binary liquid mixtures. The systems of two (or three) nonlinear differential equations were proposed to find the change of concentrations of ACh, AChR complexes, and ferment acetylcholinesterase. The main findings of our study: the linear size of the activation zone was evaluated; the process of postsynaptic membrane activation was described as a cooperative process; different approximations of ACh synchronous release were examined; stationary states and types of singular points were studied for the proposed models of ST; the nonlinear kinetic model with three order parameters demonstrated a strange-attractor behavior.