Odors arrive in small packets—tiny bouquets of molecules—that are inhaled. Receptor cells inside the nose respond by producing a series of electrical spikes, which are communicated to the olfactory bulb in the brain, where the smell is decoded.

“It’s like Morse code,” said Upinder Bhalla, a professor of neurobiology at the National Centre for Biological Sciences in Bangalore, India, and lead supervisor of a recent study about the olfactory system that is the first to document the coding is linear. “The pattern and spacing of the clicks make different letters.”

— Read more at Scents of Smell Rooted in Math at The Wall Street Journal.