Nitric oxide: what can it compute?

Abstract

Nitric oxide, a messenger molecule that diffuses over large distances in cortical tissue, may underlie a form of non-local, non-synapse-specific learning. This non-locality leads to issues that are commonly ignored in Hebbian learning rules. We discuss these issues and extend neural field theory to investigate the role of the diffusing messenger NO. This analytic framework is used to show that NO could develop cortical maps without the need for lateral-inhibitory interactions. We argue that this is a more plausible model for map-formation in early development when lateral interactions are immature. Maps formed by this NO mechanism have a specific dependence on the properties of the diffusing messenger NO. These dependences are extracted from the model and can be explored in experiments.