Why do smells create some of our strongest memories?

One of  the memory centers of the brain, the hippocampus, is closely connected with the sense of smell. Smell signals make just once stop - in the olfactory bulbs - before making their way straight to the brain.

This nearly direct connection may account for the sometimes surprisingly vivid memories that can be stirred by odors. If you were upset by your first day in school on a long-ago autumn day, the smell of fallen leaves can bring back the experience in excruciating detail. If the smell of blooming honey suckle accompanied your first kiss, the same smell, even a lifetime later, may take you back in time and place. When the painter Marc Chagall returned to Russia, his original homeland, for the first time in half a century, it was the overpowering scent of wild violets that brought back to him most vividly memories of his youth. Holding two wilted bouquets, he said; Smell, smell. No other flowers have that smell. I haven't known it in 50 years."

Smell and memory play a more direct role in what foods you like to eat,. If a certain food once made you sick, the mere whiff of it can make your stomach queasy. On the happier side, a certain kind of food can be irresistible because of your pleasant associations with it in the past.