“I’ve just had an odor evoked autobiographical-memory” …or something to that effect that is a phrase far more common than deja vu for me, and far more powerful. It is the ‘thrust back in time’ sensation you experience when you smell something that brings up a memory from your past. Far more intense than feeling carpet that reminded you of your family home or hearing the same bark as ol’skippy your first ever pet. And this is because your olfactory bulb, the smell receptor of your brain is connected to the amygdala and hippocampus, the memory storing parts of your brain.
This means that when you smell something for the first time it has been directly imprinted into your brain. This is why memories linked to smells are stronger and more vivid. BUT it is also why we only get thrust back in time to our most distant past, childhood, because childhood is when we smell most things for the first time. Smell associated memories are unique because they combats what is known as our reminiscence bump, the name for the phenomenon of us not being able to remember much before adolescence.
Bypassing the bump, smell memories can be divided into two types of memories, ones that you formed before the age of 10 and ones you formed between the age of 10 and 20. Using Functional magnetic resonance imaging (FMRI) researchers found that smells associated with memories before 10 years old lit up a part of the brain called the orbitofrontal cortex, an area connected to perception, and the later memories lit up the left interior frontal gyrus, a part of the brain that handles more conceptual memories.
Personally, I smell a lot of things that bring me right back to my 3 foot tall days and this is because somewhere in my childhood I developed hyposmia, a reduced sense of smell, and in my case, a significantly reduced sense of smell. But I wasn’t aware of this until later. In my case, despite having severe allergies, and just a general faulty sniffer, my hyposmia was caused by a trauma to my nose. Now, this sounds like I’m about to confess a traumatic event that took courage and perseverance to overcome, and it would be nice to be able to pin down this ‘trauma’ to a single incident, and often, after finding out about this, I would fantasise about what could have happened. I imagined with a fantastical view, the way a young girl imagines her first date would go if Elliot Rawson from seventh form would ever asked her out. I imagined a beautiful summers day, birds chirping, kids laughter echoing from across the bright lush field. It would be on a family picnic in a park. It had to be a picnic, otherwise I couldn’t justify the imaginary picnic blanket that I would be sitting on because my imaginary allergies would be going crazy sitting on all that freshly mowed grass. Either that… I have to halt my daydream for a moment and imagine remembering to take an antihistamine 30 minutes before the picnic. Whew. My imaginary self, did! It’s a beautiful day, when all of a sudden, in slow motion, a wonky drop kick sends a stray rugby ball spiraling in my direction, an elegant Fibonacci spiral inching closer and closer to my face. Everyone sees it and hurdle their weight towards me. But their efforts are in vain. It’s too late. Contact. I’m forced backwards like a character after a well-placed kung foo movie kick. Still in slow motion, I land on the cushioning grass, bounce slightly and then settle.
This was my fantasy trauma, which would be beautiful and highly possible…if I wasn’t the younger sister of two brothers six years my senior. Head trauma came thick and fast in my youth, from face snooker; the act of rebounding a tennis ball off of a wall to hit an oblivious passer-by (always me) in the face, or, just simply being trapped in a sleeping bag and dragged feet first down two flights of stairs. Actually for this one I wished I had anosmia, a complete lack of smell, because trapping your sister in a sleeping bag wasn’t enough, my brothers felt the need to fart in there as well.
It wasn’t until I was 15 that I had an operation to help me breath through my nose (an issue related to my allergies) and incidentally also help to regain my full sense of smell. So in the critical odour induced conceptual memory forming period of 10 – 20 my olfactory bulb was significantly impaired. Which is why I think that I have even more vivid smell memories from when I was younger than 10.
But the very first smelljavu I experienced was only days after my operation. Walking past Lush, a handmade organic soap store whose fruity, sweet odour can be smelled
from miles away; a distance I am almost certain of as our noses can detect a specific odour molecule in concentrations of 2 molecules per million, and this store’s air molecules were dense with the stuff. With friends, I walked past the viscous waft and managed to diagnose one unique odour from the scent chaos of the store. A particular molecule had drifted its way onto my olfactory epithelium, the two postage stamped sized landing pad for smells. I had no idea of the why I was drawn to this one smell. I heroically signaled for my friends to go on without me, “save yourselves” I said as I spared them from what was to be an evolutionary feat in tracking. Equipped with my 2 shiny and new working nostrils I stereoscopically hunted my prey, like that of the forked tongue of a snake, I pinpointed my preys exact location. My prey were several. Three flesh coloured oblongs of pure memory hidden in a four walled smell symposium. Yet, having located the scent package I was still unable to diagnose it’s significance. My smelling was out of practice. I stood there for several long minutes huffing a bar as my brain filtered through the 20,000 genomes in my body and then the 1,000 genomes that code for olfactory receptors. My mind had to grapple with 5% of my entire make up to try pair this particular molecule with it’s appropriate memory, and I’m crap at jigsaws!
Then, Just like in my trauma fantasy. WHAM! I was kung-fu kicked back to scribbling on a colouring in book on the ground of my childhood bedroom. I finish colouring Samba Dancer Barbie’s dress and proceed to the pièce de résistance, the cherry scratch and sniff sticker to be placed atop her fruit ladened headdress. I line it up, press it down. Perfect. I scratch and ZOOM, I’m back in the store.