Posted in Psychology & Medicine

Proust Effect

In his novel In Search of Lost Time, French writer Marcel Proust explored the power of smell in invoking memories. He tells a story of how he would have tea-soaked madeleine to trigger memories from his childhood. Proust called these memories involuntary memories, because it is not recalled on purpose, but automatically triggered by a sensory stimulus such as smell.

Our brain processes memory in a strange, abstract way. Because it doesn’t record memories like a photograph or video, memories become unreliable the older they are. We have very limited memories of our childhood, unless they are paired with specific emotions or memorable events.

Smell triggers involuntary memories because the part of the brain that senses smell, the olfactory bulb, lies right next to the hippocampus and amygdala. These sections of the brain handle memory and emotion respectively, so there is a theory that we form memories linked to different smells, especially if it is an emotional one. There is also some research to suggest a phenomenon called reminiscence bump, where we have a tendency to recall more triggered memories from adolescence and early adulthood. This may be because these are the years when we form our self-identity.

This may be why smells of certain dishes or baking may act as powerful mediums to recall treasured childhood memories, such as the love we received from our parents. Even as adults, we all have specific dishes that we crave to comfort us when we are feeling stressed or lonely. More often than not, these dishes will have a story behind them, whether you remember it consciously or not. When we smell the dish being prepared, we become drowned in nostalgia. The emotions of happiness, safety and love linked to these memories distract us from the pains of life for just long enough that we can have the strength to make it through another day.

Proust talked about a tea-soaked madeleine being his key to his memories. What food is the proverbial madeleine to you?

What food triggers your nostalgia?

Posted in Psychology & Medicine

Synaesthesia

What colour do you associate with the letter “E”? What sound do you hear when you feel the fluffiness of cotton? These sound strange to most people as we experience the senses in distinct ways. However, for 4% of the population, this is a completely normal experience.

Synaesthesia (“joined sensation”) is the neurological phenomenon where two or more senses are coupled together. This creates two kinds of synaesthesia: projection, where you physically sense something (such as seeing a purple circle when hearing piano music), and association, where you associate the sense with another sense (“that sounds quite orange”).

The most common form of synaesthesia that is reported is grapheme-colour synaesthesia, where certain people perceive letters and numbers as different colours. However, there are various kinds of synaesthesia, such as chromesthesia, where people associate sounds with colours (previously called “coloured hearing”). In fact, almost every combination of senses have been described, with some individuals experiencing multiple senses at the same time.

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The exact origin and mechanism of synaesthesia are yet to be fully explained. The most likely explanation is that in the brain of synaesthetes, the neural pathways for the various senses cross-over more than they should, causing the simultaneous activation. There are already some cross-overs between these pathways, as evidenced by various sensory illusions that the average person can enjoy. For example, a ventriloquist can fool the audience into thinking the puppet is talking as we hear speech and see the puppet’s mouth moving.

An alternative explanation is that there may be an element of ideasthesia – where concepts are paired with sensory experience. This would mean that synaesthetes are experiencing sensations due to the idea something represents, not because of the original sensory stimulus.

For example, when a synaesthete describes that the word “tree” tastes like brie cheese, it might not be the sound of the word, but rather the concept of a tree that triggers the sensation. We actually see examples of this in day to day life in the form of metaphors. We describe a wine having a round taste or a person being sweet.

There is much to learn about the phenomenon, but synaesthesia has already deepened our understanding of how we perceive the world, process it and commit it to memory through the use of associations and mnemonics.