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Why Smells Trigger Memories Faster Than We Expect · Understanding the Brain

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  Speaker 1: Today we're going to be looking at our past memories.
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  Speaker 1: So picture yourself walking into a house you've never visited before.
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  Speaker 1: Someone is cooking dinner and suddenly without warning you're eight
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  Speaker 1: years old again. You remember your grandmother's kitchen, the afternoon
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  Speaker 1: sunlight coming through the window, the sound of dishes being washed.
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  Speaker 1: Perhaps even the feeling of being safe, loved and completely
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  Speaker 1: unaware of the responsibilities that adulthood would eventually bring. All
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  Speaker 1: of this happens because of a smell. Why does something
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  Speaker 1: as ordinary as an odor have the power to resurrect
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  Speaker 1: experiences we haven't consciously thought about in decades? The answer
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  Speaker 1: begins with biology. When we smell something, airborne molecules enter
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  Speaker 1: the nose and bind to specialized receptors in the olfactory epithelium.
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  Speaker 1: These receptors send signals to the olfactory bulb, which processes
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  Speaker 1: information about the odor. And like most sensory systems, it
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  Speaker 1: goes through the thalamus before reaching the primary sensory cortex.
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  Speaker 1: But this isn't a neuroscience description. But that's kind of
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  Speaker 1: what happens. And the hippocampus plays a central role in
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  Speaker 1: forming and retrieving what we call autobiographical memories. And this
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  Speaker 1: helps explain why smells can evoke memories that feel unusually emotional, vivid,
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  Speaker 1: and personal. At least, that's the biological explanation. Researchers sometimes
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  Speaker 1: call this the Proust phenomenon, named after Marcel Proust's famous
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  Speaker 1: literary description of memories awakened by the taste and aroma
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  Speaker 1: of a madeleine. But neuroscience only explains part of the
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  Speaker 1: experiences I mentioned. From a psychodynamic perspective, smells also activate
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  Speaker 1: internal representations of important relationships. Consider a woman who smells
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  Speaker 1: her deceased mother's perfume. She may immediately experience sadness, warmth, longing.
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  Speaker 1: The scent does not simply remind her of a person
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  Speaker 1: as it activates an emotionally meaningful representation of that relationship.
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  Speaker 1: Object relations theory proposes that we internalize aspects of our
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  Speaker 1: early relationships, including emotional expectations, feeling of safety, conflict, experiences
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  Speaker 1: of being cared for. The familiar scent may become associated
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  Speaker 1: with these relational experiences. The smell of a father's jacket
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  Speaker 1: might evoke security. The odor of a childhood hospital might
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  Speaker 1: bring back anxiety. A particular meal might remind someone of
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  Speaker 1: family affection and of arguments that occurred around the dinner table.
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  Speaker 1: These reactions do not necessarily involve repression or unconscious conflict.
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  Speaker 1: Many can be understood through ordinary associative learning. However, psychodynamic
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  Speaker 1: thinking encourages us to ask another question. Why does this
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  Speaker 1: particular memory matter? Perhaps someone experiences overwhelming nostalgia for a
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  Speaker 1: childhood home even though their childhood was complicated. The smell
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  Speaker 1: may evoke a moment of security that existed alongside disappointment, loneliness,
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  Speaker 1: or conflict. Psychodynamically, this illustrates ambivalence, the capacity to experience
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  Speaker 1: love and resentment. Interestingly, odor-evoked autobiographical memories are often older
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  Speaker 1: and more emotionally evocative than memories prompted by words or
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  Speaker 1: visual cues. And there is another fascinating possibility. Sometimes we
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  Speaker 1: experience the emotion before identifying the memory. A scent makes
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  Speaker 1: us inexplicably sad, yet we cannot immediately explain why. The
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  Speaker 1: emotional association may be activated before we consciously reconstruct the
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  Speaker 1: autobiographical context. Smell reminds us that memory is not simply
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  Speaker 1: a recording of the past. It is a reconstruction shaped
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  Speaker 1: by biology, emotion, internal relationships and the meaning we assign
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  Speaker 1: to our experiences. Sometimes the shortest distance between adulthood and
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  Speaker 1: childhood is a single breath.