Energy and information in Hodgkin-Huxley neurons

TL;DR

This paper uses the Hodgkin-Huxley model to analyze the energy efficiency of neural information transmission, revealing that optimal efficiency often occurs at low energy consumption levels, especially in neuron groups.

Contribution

It interprets the Hodgkin-Huxley circuit as an energy model and evaluates metabolic energy use in neuron communication via electrical synapses, highlighting conditions for optimal energy efficiency.

Findings

Maximum energy efficiency in a single neuron requires maximum energy use.

Groups of neurons can achieve high efficiency at low energy costs.

Optimal transmission efficiency occurs at relatively low metabolic energy consumption.

Abstract

The generation of spikes by neurons is energetically a costly process and the evaluation of the metabolic energy required to maintain the signalling activity of neurons a challenge of practical interest. Neuron models are frequently used to represent the dynamics of real neurons but hardly ever to evaluate the electrochemical energy required to maintain that dynamics. This paper discusses the interpretation of a Hodgkin-Huxley circuit as an energy model for real biological neurons and uses it to evaluate the consumption of metabolic energy in the transmission of information between neurons coupled by electrical synapses, i.e. gap junctions. We show that for a single postsynaptic neuron maximum energy efficiency, measured in bits of mutual information per ATP molecule consumed, requires maximum energy consumption. On the contrary, for groups of parallel postsynaptic neurons we determine values of the synaptic conductance at which the energy efficiency of the transmission presents clear maxima at relatively very low values of metabolic energy consumption. Contrary to what it could be expected best performance occurs at low energy cost.