How your brain links scents and music to memories

Researchers at the University of California have discovered that specific neurons in the medial temporal lobe, the famous memory center of the brain, are involved in making associative memories. These neurons, known as fan cells, are located in the entorhinal cortex and are activated by dopamine, a neurotransmitter involved in pleasure and reward. This research, published in the journal Nature, reveals that the release of dopamine is crucial for forming new scent associations.

Reward system

According to Professor Jos Prickaerts, who specializes in experimental neuropsychopharmacology at Maastricht University, this study connects two classical fields in memory research: cognitive mapping and associative learning. The reward system appears to have a direct connection with the memory system, raising new questions about how these mechanisms operate in humans, particularly in conditions like Alzheimer's.

Professor Eddy van der Zee, a neurobiology expert at the University of Groningen, praises the study for its elegance and technical execution. He emphasizes that only scent associations are formed when sufficient dopamine is released as a reward. Without this reward, fan cells are not adequately activated to store a new association. This raises questions about how negative scent associations work. There may be specialized fan cells that respond to negative stimuli, such as fear, regulated by the amygdala.

Dopamine deficiency

These findings may also have implications for conditions such as Parkinson's disease, where dopamine production is disrupted. The ability of Parkinson's patients to form scent associations may be diminished due to a dopamine deficiency. Many people with Parkinson's report a decrease in odor perception long before motor symptoms such as tremors and muscle stiffness appear. This research provides new insights into how scent associations are stored and raises questions about the role of fan cells in other memory mechanisms.

The effects of music on the brain

A similar cellular mechanism may underlie the memories that music can evoke. For example, researchers have shown that music can be a strong stimulus for eliciting autobiographical memories. This is likely because music can evoke a certain emotional alertness (Eschrich 2008). This works in two directions: emotions act as a catalyst for storing and recalling memories; the stronger the emotion associated with the memory and the more vivid the memory, the better the memories are stored, and listening to that same music later can easily evoke that emotional alertness along with the associated memory. On the other hand, music can also directly evoke emotions that then affect the memory process. Here too, dopamine and the reward provided by music are involved (Lee 2021, Ferreri 2017).

Recalling memories with visuals, scents, sounds, and music

By cycling virtually with Bike Labyrinth, many people also reminisce; they might pedal through their hometown and vividly recount adventures from their past. We can easily imagine that certain scents and music accompany these memories. Perhaps it would be enjoyable to create a playlist of music that residents have fond feelings for, or a bouquet of flowers with scents directly from a memorable vacation or from a neighbor's garden. Consider turning on the sound with Bike Labyrinth too; for instance, on the nature route Pont du Gard, you can hear the crickets chirping and transport yourself back to a sunny vacation in southern France. Enhancing the cycling experience this way makes it even more realistic and can provide an additional boost of dopamine while cycling.

For more information on this topic, you can find the original, Dutch, article on EOS Wetenschap here.