The Powerful Link Between Smell, Memory, and Emotion

Smells may seem transient, but remembering smells from childhood and reliving those moments and emotions is a nearly universal human experience. Why do smells trigger memories? And how is smell connected to memory? The team at FragranceX has created a scent memory guide to explore these questions and more facts about smell and memory:

The Powerful Link Between Smell, Memory, and Emotion - - Infographic

What Is it Called When a Smell Brings Back a Memory?

The powerful phenomenon of scents triggering nostalgia is called the Proust effect, or the ability of odors to spontaneously cue autobiographical memories that are deeply vivid, emotionally evocative, and unfazed by the passage of time. The name originated from the 20th century French novelist Marcel Proust, who described how the smell of a pastry he dipped in tea sparked a rush of joy along with rich recollections of his childhood. This term can be applied to sudden and intense recollections triggered by other sensory stimuli as well.

Why Do Smells Bring Back Memories?

It likely comes as no surprise that our sense of smell is closely linked to memory. People often describe how a smell conjures up memories so pure and intense that it can feel as if they are living the event once again. These memories are often called scent-linked or odor-linked memories. Not only do smells have the power to spark such dynamic memories, but they can make us feel similar emotions to those we may have experienced during the episode. So (why are odors linked to memories?) Scientists believe that this may primarily be due to the structure and layout of the brain itself. A study by Northwestern Medicine discovered a neural basis for how the brain allows odors to provoke such strong memories. In simple terms, the olfactory processing system (the bodily structures that serve the sense of smell, including the nose, naval cavity, and olfactory bulb) is close in physical proximity to the memory and emotion hub of the brain. What is the olfactory bulb? It is the part of the brain that receives and processes scent molecules. The amygdala, the almond-shaped brain structure involved with emotion, and the hippocampus, the area responsible for memory and learning, are tight neighbors with the olfactory bulb and are directly connected to each other. That means that your brain uses the same area of the brain to process emotion and memory as it does smell. Smell is the only sense that gets processed in this region of the brain, which explains why it is so strongly tied with emotion and memory.

Other sensory information (from sight, touch, or taste) gets sent to the thamalus, which serves as a checkpoint, relay station, and gateway to consciousness. Odor bypasses the thamalus and is received directly by the olfactory bulb, which is why it outperforms other senses in its ability to awaken memories and feelings.

How Many Smells Can the Human Nose Detect?

According to the National Institutes of Health, humans can distinguish more than 1 trillion scents! Odors are almost always made up of a mixture of components in various ratios, much like perfumes. For example, the scent of a rose is a mix of 275 components, with only a few creating the actual smell we can perceive.

How Many Smell Sensors Do Humans Have?

Humans have more than 400 olfactory receptors, which is staggering to imagine compared to the four types of light sensors and four types of touch receptors we possess. This may explain why we can identify more than 1 trillion smells but only several million colors and half a million tones.

The Powerful Link Between Smell, Memory, and Emotion

Smell has a stronger link to memory and emotion than any of the other senses.

We are 100 times more likely to remember something we smell versus something we see, and 75% of our everyday emotions are influenced by smell.

Thamalus = Sensory Checkpoint

When you hear, touch, or taste, the sensory information reaches the thalamus, which serves as your brain’s relay station. It then sends the info to relevant brain areas such as the hippocampus, which is responsible for memory, and the amygdala, which processes emotion.

Smells bypass the thalamus.

Smells go straight to the olfactory bulb, or the brain’s smell processing center. This bulb is directly linked to the amygdala (responsible for emotion) and hippocampus (responsible for memory).

Direct Link = Intense Association

The olfactory bulb’s proximity to the brain’s emotion and memory centers might explain why scent can immediately trigger a vivid memory or strong emotion.

If we are visual creatures, why is smell so powerful?

Some scientists believe it goes back to how we evolved: Smell is one of the most fundamental senses, originating in single-celled organisms as a way to interact with the chemicals around them.

We have at least 400 different types of smell receptors (but only four types of light sensors and four types of touch receptors).

The long evolutionary history of smell may explain why we have so many smell receptors compared to our other senses.

A Shocking Odor-Linked Memory Discovery

In 2017, scientists discovered that some memories may be saved in part of the olfactory bulb itself, called the piriform cortex. They found that it processes and stores long-term odor-linked memories, but only when “instructed” to do so by the orbitofrontal cortex, a higher brain area.

Scents are doubly effective at triggering memories.

So not only is the scent-processing center connected closely to the memory center, but it is also capable of archiving long-term memories in-house.

Scent branding may be making you buy more.

Many stores and hotels have specialized scents created by scent branding companies like ScentAir. Hugo Boss has a musky aroma with a touch of citrus in their stores.

Department stores have a scent for each section.

For example, Bloomingdale’s uses a coconut scent in swimwear, lilac in lingerie, and baby powder in children’s. How can you not buy a bathing suit with memories of the beach sailing through your brain?

Old Navy embraces seasonal smells.

Old Navy uses seasonal scents with notes such as cinnamon, nutmeg, clove, evergreen, cranberry, and cedar. These nostalgic aromas spark fond memories of merriment and warm, fuzzy emotions.

Hyatt Place and Scent Branding

Hyatt Place has been leveraging the powerful link between scent, memory, and emotion since its inception in 2007. Its unique “Seamless” signature scent aims to create a sense of welcoming elegance and calm with a blend of fresh blueberries, light florals, warm vanilla, and musk. Regular surveys and online reviews found that the scent enhanced the guest experience and increased brand memorability.

Could aromatherapy improve worker performance?

A study by Takasago, Japan’s largest fragrance producer, found that workers made 54% fewer typing errors when the environment was scented with lemon. This may be because linalool, a substance found in lemons, helps relax our flight-or-fight stress reflex, improving focus.

Lavender = Stress Relief

Researchers found that lavender and rosemary may decrease the stress hormone cortisol.

Sensory Marketing = Powerful Unconscious Cues

The Sensory Marketing Laboratory at the University of Michigan has found that the senses can work together in marketing. For instance, because cinnamon suggests warmth, a heating pad’s appeal and perceived effectiveness can be enhanced by making it cinnamon-scented.

Nothing Like the Smell of Fresh Coffee

A scent marketing campaign for Dunkin’ Donuts in South Korea had coffee aromas released from atomizers every time the company jingle played on public buses. This increased visits to Dunkin’ Donuts stores near bus stops by 16% and sales for those stores by 29%.

Another Win for Coffee

A convenience store that released coffee scent near the gas pumps increased coffee purchases by 300%.

Signature Scent = Better Recall

One study found that imbuing pencils with the distinct smell of tea tree oil dramatically increased its user’s ability to remember the brand and other details two weeks later.

Flower Power

Two identical shoes were placed in identical rooms, one floral-scented, the other not. By an 84% margin, customers preferred the shoes in the floral room and estimated their value to be an average of $10.33 higher.

Puzzling Petals

Volunteers in one study completed puzzle-solving tasks 17% faster after exposure to floral fragrances.

Inhale Vanilla, Exhale Anxiety

Sixty-three percent of MRI patients who smelled vanilla before a procedure reported reduced anxiety compared to just 4% of patients who didn’t.

The Sweet Smell of Risk

A mid-1990s study at a Las Vegas casino found that the amount gambled in a scented slot machine area increased by 45% compared to an unscented room.

Switch Perfume to Help Heal Heartbreak 

Psychologist Julie Walsh-Messinger, who studies olfaction, emotion, and social behavior, stated that switching your perfume may help you escape the bad memories linked to it and create new ones.


“The smell and taste of things remain poised a long time, like souls, ready to remind us.” — Marcel Proust 

“When you try a new perfume, you are trying an odor that has no associations, so it gives you the possibility to make new ones and write new memories.” — Alfredo Fontanini, M.D., Ph.D.

“Long after one has forgotten what a woman wore, the memory of her perfume lingers.” — Christian Dior

“Ladies, a man will never remember your handbag, but he will remember your perfume.” — Olivier Creed

“Perfume is that last and best reserve of the past, the one which, when all our tears have run dry, can make us cry again!” — Marcel Proust

“Perfume is the art that makes memory speak.” — Francis Kurkdjian