The phenomenon of olfaction commences with the olfactory fibres lining the nasal cavities in the nose. When the air enters cavities, a few chemicals present in the air associate activating the nervous system receptors on the cilia. This stimulus gives signals to the brain.
Neurons consume signals through openings in ethmoid bone from nasal cavities and to olfactory bulbs. Then, the signal moves from the olfactory bulbs all through the cranial nerve 1 and the olfactory region in the cerebral cortex.
More here:
- What Are Regions Of The Olfactory Cortex?
- What Are Olfactory Receptors?
- Sensory Receptors
- What Is Phantosmia?
