By Vatsala Mamgain Jun. 28, 2016
Wonder what’s with the nos(e)talgia? Well, science explains how smells ring a bell.
y grandfather had a smell that was peculiarly his – a gentle, beloved, nana smell. It was for me, the smell of childhood happiness. It was a mixture of the smell of recently-mown grass, Panama cigarettes and Godrej shaving rounds. He died almost a million years ago, but even today, a mere whiff of any of these will bring back memories of entire vacations spent at his home – of cool, crisp, sunny days spent lying in his garden, sucking on blades of grass, as he pruned his trees and rose bushes.
That sulphurous stink, just short of rotting eggs, rough and acrid, makes your heart burst with happiness, because actual Diwali firecrackers were the backdrop to your first kiss. The smell of chlorine will always bring back the joy of learning to swim and clambering up to the high boards to jump into the welcoming water.
Given that we are all familiar with these “fragrance flashbacks”, the question really is: What is it about the sense of smell that has the power to unlock forgotten memories so vividly?
Science is just beginning to unravel the mystery. The theory is that our olfactory bulb, which is responsible for processing smells, is located right next to the amygdala and hippocampus brain regions – the ones that control emotion and memory.
This is in direct contrast to visual, sound and touch memories, which do not pass anywhere near these areas. Simply put, our nose alone has “approach” or “pull” with the memory and emotion centres of the brain. That explains why smells unlock such powerful emotional memories.
The olfactory sense is one of the first to mature – so babies at birth show a marked preference for the smell of their own mothers’ amniotic fluid than others. It is also one of the first ways by which we experience the world around us – when babies put everything into their mouths, there is a tactile as well as olfactory experience that registers.
Even between adults, smell is a major determinant of sexual attraction – it has been hypothesised that a kiss is really just a polite way (or an arse upwards way, if you will) to do what doggies do so unabashedly, i.e. sniff around hopefully.
Research shows that unlike visual and auditory memories, which are formed in late teenage and early adulthood, our olfactory memories are typically formed in childhood, and tend to be both fairly specific and emotion driven. So when I look at a tin of talcum powder, it evokes general memories of pre-liberalisation, pre-deodorant India, when a liberal dousing of powder was the first and last defence against stinking up the room.
Research shows that unlike visual and auditory memories, our olfactory memories are typically formed in childhood, and tend to be both fairly specific and emotion driven.
A whiff of Cuticura talc conjures up my wonderful Jayanti Mami; a sweet but crazy old bat, racist as they come, who was so distraught at my dark skin colour that she “improved” me before every family function by trapping me between her large knobbly knees and dusting my face with a liberal sprinkling of the powder. It also conjures up – rather disturbingly – her large, white, flaccid armpits and expansive, pillowy bosom, which proves that while the nose might be a time machine in most cases, it can also trigger post-traumatic stress in a few.
Studies have proven that newer visual or audio memories can overwrite older ones, but with olfactory memories the older ones tend to stick longest.
This might explain why the face of your first crush in middle school may now be a composite of the faces of all your crushes since. But the smell of plasticine will only retrieve the memory of that kindergarten table with the fat boy who ate his own burps and whose forefinger was perpetually on an extended exploratory journey up his nose. (Given that olfactory memory is so specific and rich and emotional, it’s just bad luck that one can’t sniff ones way to learning the periodic table – smell memory is more linked to perception than fact.)
However, smell and memory are linked inextricably – loss of smell is one of the earliest markers for patients of Alzheimer’s and dementia.
So, the next time you catch a whiff of sandalwood soap and find yourself bursting into tears remembering your wonderful grand-aunt, or are transported to an open jeep with your extended family in the rain when you smell the world famous fragrance “wet dog”, remember that what you’re experiencing is the emotional underbelly of having a nose – and give thanks that for some time at least, you’ve managed to keep dementia at bay.