Why does a smell from the past put a smile on your face?

Can a smell trigger memories?

Have you ever felt very nostalgic when you smelt a childhood scent? Or wonder why it feels so great when you smell a perfume which your partner wore the first time you met! Even normal items like hair spray, freshly baked apple pie, fresh cut grass and even an old newspaper can all trigger memories.

How come we can relate emotion and memories to smell triggers?
Those vivid emotional memories that are often triggered by various scents and smell is called Odour-evoked autobiographical memory.

There have also been scientific studies using a variety of approaches to back up this anecdotal evidence. One of the first was a study led by Dr. Rachel Herz at Brown University in 2004. Herz and her collaborators found that a group of five women showed more brain activity when smelling a perfume with which they associated a positive memory than when smelling a control perfume they had never before smelled. The brain activity associated with the memorable perfume was also greater than that produced by the visual cue of seeing the bottle of perfume.

The answer is likely due to brain anatomy. Interestingly, visual, auditory (sound), and tactile (touch) information do not pass through these brain areas but the olfactory bulb (the organ used for smelling) is directly connected to the bottom of the brain. This may be why olfaction, more than any other sense, is so successful at triggering emotions and memories.

The power of scents to trigger memories is proof of why aromatherapy is effective!

Odor-evoked autobiographical memories occur by chance when you happen to smell a familiar scent that triggers the memory. However, smelling scents to trigger real physical and emotional responses is what aromatherapy is.

Here is some information from past research:

Sweet orange oil has been found to have anxiety-inhibiting effects in humans, supporting its common use as a tranquilizer by aromatherapists.

Reference: https://www.ncbi.nlm.nih.gov/pubmed/22849536

Some women who were exposed to orange odour in a dental office had a lower level of anxiety, a more positive mood, and a higher level of calmness. Researchers concluded, “Exposure to an ambient odour of orange has a relaxant effect”.

Reference: https://www.ncbi.nlm.nih.gov/pubmed/11134689

One study found that the scent of Green Apple significantly relieved migraine pain. This may also work with other scents that you enjoy so consulting with an aromatherapist might be beneficial.

The smell of peppermint has been shown to enhance memory and increase alertness
A blend of peppermint, ginger, spearmint, and lavender essential oils has been found to help relieve postoperative nausea

Reference: https://www.ncbi.nlm.nih.gov/pubmed/24461277

Lavender fragrance has been shown to lessen pain following needle insertion

Reference: https://www.ncbi.nlm.nih.gov/pubmed/24439636

Smell really is a significant part of our lives. But remember, before you start making your house smell really great, you have to make sure the air is fresh and clean first! That is why having a good quality air purifier will be very helpful. Removing airborne pollutants makes your indoor air fresher and cleaner then all you have to do is add some water-soluble fragrances of your choice to bring give your house the fragrant aroma that you desire!