As a person inhales, air and scent molecules move past the smell receptors in the nose. In turn, the smell receptors relay a signal to the brain. Smells can trigger memories and emotional responses.
Update Date 10/27/2014
Updated by: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.