Synaptic and Ephaptic Proposals for Selective Attention: A Comparative Study

" The ephaptic coupling framework offers elegant simplicity and a potential physical substrate for selective attention: physics automatically selects and amplifies information-rich signals through local electromagnetic interactions. No inference, no hierarchy, no complex computation required—just coupled axons behaving according to electromagnetic principles. For the giraffe on the desk, Friston predicts a five-stage cascade of prediction errors, precision weighting, and hierarchical revision—mechanisms with empirical support from neuroimaging and electrophysiology. Chawla and Morgera suggest something more direct: the high-entropy visual signal simply dominates in the optic nerve through ephaptic coupling, ensuring robust propagation to cortex. This latter proposal, while mathematically elegant and computationally efficient, awaits experimental confirmation (see boxed sidebar in Section I for scientific status). The ephaptic framework proposes what cognitive theories have long sought: a physical substrate for selective attention operating at the level of electromagnetic field interactions and extracellular currents in axon tracts. Rather than treating attention as a computational process implemented by synaptic circuits, it would emerge from the physics of information propagation. The nervous system wouldn’t choose what to attend to—high-entropy signals would choose themselves through physical dominance in coupled pathways." {Credits 1}

{Credits 1} 🎪 Chawla, A. (2025). Synaptic and Ephaptic Proposals for Selective Attention: A Comparative Study. Zenodo. https://doi.org/10.5281/zenodo.17621219. © 2025 The Authors. This article is licensed under a Creative Commons Attribution 4.0 International License.