Olfactory sensory neuron

An olfactory sensory neuron is a neuron that detects odorant molecules and sends an electrical signal toward the brain. Receptor-bearing sensory endings sample chemicals at the nasal surface, while the axon carries the resulting output toward the olfactory bulb. Detection and interpretation are therefore distributed across peripheral cells and central circuits.

Genetically labelled receptor-expressing neurons allowed investigators to trace where their axons converged in the olfactory bulb. Receptor-swap experiments further tested how receptor identity contributes to that projection pattern. ^[ref] This connects molecular recognition to circuit organization without implying that a single active neuron uniquely identifies every odour: an odour can recruit a pattern across receptor classes.