Whether it’s roses, fresh cookies, or a skunk, when you get a whiff of something, molecules travel through your nose and to your odor receptors. This pathway then triggers the olfactory bulb in the brain’s limbic system, and fragrant magic happens. Memories rush back, appetites roar, or something screams, “Get the Lysol!”
This whole process is pretty intense for your brain. To keep your nervous system from exhausting itself with continuous stimuli, the receptors experience temporary sensory fatigue, or olfactory adaptation. Odor receptors stop sending messages to the brain about a lingering odor after a few minutes and instead focus on novel smells. That’s why your nose adjusts to your coworker who wears too much cologne, but perks up again when he eats pad thai at his desk.