the.com/sense of smell
The only sense wired straight to memory, which is why a smell can time-travel you.
means The sense that detects airborne chemicals through the nose, letting you identify food, danger, and even other people before you see them.
from English 'smell' itself has a murky history — it shows up in Middle English but no one has nailed down a confirmed older root, so dictionaries mostly shrug and call it 'origin uncertain,' possibly related to continental Germanic words with similar sniffing meanings. The scientific name for the sense, 'olfaction,' is the better-documented cousin, built from Latin 'olfacere' — 'olere' (to smell) plus 'facere' (to make or do) — literally 'smell-making.' So the plain word and the fancy word came from entirely different places and just happened to end up describing the same nose.
- direct line
- olfactory signals skip the brain's relay station, thalamus
- memory link
- smell neurons sit next to the hippocampus and amygdala
- renewal
- receptor neurons regenerate every few weeks, unlike most neurons
- range
- humans can distinguish over a trillion distinct odors