The nose has 3 uses: moisten air and filter it as we breathe, and to facilitate smell.
Our sense of smell allows us to enjoy the scent of fresh flowers, ocean breezes, and even enhances the taste of our foods. However, the sense of smell plays an even more important roll. Our sense of smell can save our lives. If we smell smoke from a fire we know to stay away, or if we smell rotten food we know not to eat it. You’ve probably heard that pregnant women have a heighten sense of smell. If you’re pregnant your sense smell becomes more discerning to protect your unborn baby.
How do we smell?
There are two olfactory membranes, smelling surfaces, under the bridge of our noses that are about as big as a postage stamp. As we breathe in the vapors are dissolved and the Olfactory nerve, the smelling nerve converts those smells into electrical signals. Generally, signals going to the brain have to travel through out the body to reach the brain. However, the smelling nerve goes straight back to the part of the brain that stores memory and feelings without any detours to the cerebral cortex. This is why there is a strong memory connection with the sense of smell.
Smells are powerful memory trigger and the relationship between smell and memory has been the subject of many studies.