There are certain smells that, the moment they reach our nose, transport us years back to an unexpected moment—perhaps to a childhood morning, the smell of chestnuts roasting on the stove, or the scent of linden trees blooming in spring. Even if we cannot yet name it, we recognize that smell. Our hearts race, our eyes mist over, or a warm smile settles on our face. But why? Why does the scent of jasmine flowers on a warm summer night, the smell of soil after rain, or the aroma of freshly baked bread transform into such powerful time machines?
Having intense effects on human behaviors and emotions, the sense of smell is considered one of the first senses to develop in the evolutionary process. The ability of smells to instantly refresh forgotten memories of a person’s life story has made this sensory perception system an interesting and specific subject of study in the fields of psychology and neuroscience (Herz, 2004). The cognitive structure of an individual typically recalls memories of previous experiences through unexpected stimuli. Smell, being the most primitive sense, has the capacity to quickly and intensely revive memories embedded in the mind through the direct integration of olfactory signals with the limbic system.
A Scent, A Memory: The Effect of the Sense of Smell on Emotional Memory
The sense of smell has a different significance when compared to other senses. Olfactory signals directly reach the amygdala, which is associated with emotions in the brain, and the hippocampus, which is related to memory. Therefore, smells form connections with intense emotions and can become long-lasting in memory. Smells can bring back memories recorded in a person’s subconscious or suppressed memories, early childhood experiences, often accompanied by intense emotional reactions (Herz & Schooler, 2002).
Scent, Memories, and Emotions: The Proust Effect
The phenomenon of recalling past experiences that hold meaning for an individual with emotional intensity is referred to as the “Proust Effect.” An example of this can be found in the case of Marcel Proust’s “Madeleine Cookie.” In this example, Proust describes how, while dipping a madeleine cookie into his tea, he was suddenly reminded of a childhood experience. This experience unexpectedly revived memories of his childhood spent at his aunt’s house and reawakened suppressed emotions. Proust demonstrates that smells not only evoke past memories but also provide an opportunity to re-experience intense emotions. Such experiences are referred to as the “Proustian experience” (Ozan, 2021, p. 248).
As seen in the above-mentioned example, smell is directly connected to the emotional memory of our brain. The smell and taste of the cookie evoke subconscious childhood memories, making it a phenomenon that helps us understand the memory and emotional dimensions of past experiences. It demonstrates that an individual can recreate sensory processes such as smell, taste, sound, and color in their mind. Therefore, scents cling to memories outside of consciousness, blending with feelings and finding a place in our brain. However, this phenomenon is not limited to personal experiences, as certain scents become a part of the collective mind, transforming into a societal mental imprint.
Why Do We Classify Certain Smells as Unpleasant?
Negative reactions to certain smells are rooted in an evolutionary defense mechanism. For prehistoric humans, the smell of rotten meat, toxic mushrooms, and moldy plants was a survival cue. It served as a warning, signaling “danger.” Evolutionarily, smells associated with danger trigger a reflex in the brain to initiate avoidance when a threatening situation is detected.
In this context, negative reactions to certain smells may not be innate but rather rooted in the memories we accumulate throughout our lives. For example, the musty smell of damp walls might remind us of the feeling of loneliness we experienced in our childhood home. The brain does not perceive the smell merely as a stimulus, but as the key to unlocking all of our emotions.
Conclusion
Olfactory memory is not just a silent reminder of the past but also a sign of how the human brain contains such profound and complex emotions. It shows that the human mind is not only shaped by rationality but is also intertwined with feelings and the body. As a result, olfactory memory can serve as a gateway not only to personal memories but also to the essence of being, experiencing, recalling, and, at times, emotionally strengthening oneself.
Sometimes, when we avoid a particular scent, we may actually be fleeing from our past, our fears, or a painful memory. Perhaps the reason we classify certain smells as unpleasant is not because of our noses, but because of the signal our soul is sending us.
Feelings, hidden deep within the recesses of memories, may come to life again one day, suddenly awakened by the call of a familiar smell.
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