Neuronal energy consumption: biophysics, efficiency and evolution

•Electrical signaling consumes substantial amounts of energy influencing physiology and anatomy.•Action potential energy consumption depends on the voltage-gated ion channels neurons express.•Noise, bandwidth and propagation affect energy consumption and information processing.•A law of diminishing returns penalizes excess information processing capacity in neurons.

Electrical and chemical signaling within and between neurons consumes energy. Recent studies have sought to refine our understanding of the processes that consume energy and their relationship to information processing by coupling experiments with computational models and energy budgets. These studies have produced insights into both how neurons and neural circuits function, and why they evolved to function in the way they do.