When we were young, we were fascinated with the time machines and time travel, to explore the future and rewind the past; but, what if this time machine already exists? Well, it does; only it is not made of gears and wires, but of alcohol and chemical reactions.
Would you believe it if someone told you that everybody has a time machine at home, and that it can be used whenever we want? Perfumes are our domestic time machines; these fragrances, which are made of essential oils, have a spectacular role in our memory. They evoke it and revive the past as if it never passed; this is known as Odour-evoked Autobiographical Memories.
Indeed, not only perfumes are considered stimulus of memories, odors in general are powerful reminders of our autobiographical experiences. Strong emotions and memories are brought back when a specific smell is detected; they could be triggered by the smell of a perfume, winter air, fresh air, cut grass, or even a scent of an old book; but how does this happen?
Olfaction occurs when cells in the nasal cavity send a signal to the smell-analysing region in the brain known as the olfactory bulb, which starts inside the nose and runs along the brain bottom. The olfactory bulb is connected to two parts in the brain that handle emotions and memories: the amygdala and the hippocampus; this is why scents trigger a particular memory or emotion.
Interestingly, several behavioral studies have shown that memories linked to odors are usually strong and more vivid, and that odors are better at “bringing you back in time” than images. The reason is that the visual, auditory, and tactile information do not pass through the amygdala and the hippocampus brain areas.
As you smell a certain odor, you will spontaneously bring on a flood of emotion and remember every single moment, hour, or maybe minute; the time when you got accepted into your dream college or job, or days spent with your family or friends, which were full of priceless laughter and unconditional love. Nevertheless, smells can also trigger negative emotions, particularly in individuals with Post-Traumatic Stress Disorder (PTSD). Certain smells for PTSD patients could cause them re-experiencing feelings of guilt or helplessness.
Whenever you feel nostalgic for a specific time in your life, smell your favorite time-related odor, and enjoy that time again.
Watch this video on how smells trigger memories
You might be interested too to know how memories form, and how we lose them; watch this video:
References
fifthsense.org.uk
psychologytoday.com