The Nose Knows Where Memories Go
Studying the connection between olfaction and the brain’s ability to remember things
Ever smell a certain aroma and find yourself instantly connected with a distant memory? There’s a scientific reason for that. And now, campus researchers have found that using “olfactory enrichment,” can improve cognitive recollection – and potentially help an aging society stem the growing problem of dementia and other neurological disorders. Hear more from Professor Emeritus Michael Leon in this video on how a recent UC Irvine study revealed unprecedented results tying smell to memory retention.
“The brain evolved at a time when there was plenty of olfactory stimulation. Nobody took a shower, ever, so everybody was redolent, and everything around them was odorous. In the world we’re in today, you can take a deep breath and not smell anything. There is a big downside to that.”
- Michael Leon, UC Irvine professor emeritus of neurology and behavior
Olfactory Stimulation
The sense of smell has a direct pathway to memory centers in the brain, bypassing other sensory gateways like vision or hearing, making it a potent tool for memory enhancement.
Variety in Scents
Our sense of smell typically begins to diminish in our 60s, which coincides with the ability to process memories. Scientists have found that using an array of scents is beneficial for memory stimulation due to the brain's need for novelty.
Improved Memories
Participants in the study experienced a 226% improvement in memory retention during standardized word tests after exposure to scents over a four-month period.
“The sense of smell has a privileged status in the brain. Unlike the other senses, it doesn’t have to filter through the brain’s gateways. It’s like a superhighway that directly accesses the memory parts of the brain: the hippocampus and its surrounding regions.”
- Michael Yassa, UC Irvine professor of neurobiology and behavior and James L. McGaugh Chair in the Neurobiology of Learning and Memory
Researchers at UC Irvine's Biomarker Exploration in Aging, Cognition and Neurodegeneration (BEACoN) group, which was created in 2017 to develop biomarkers for cognitive decline, analyze brain scans. The team is led by Michael Yassa, professor of neurobiology and behavior, and also includes experts from psychiatry, physics, informatics, metabolomics, pathology, statistics and computational science.
A researcher views wavelengths in associate professor Kei Igarashi's lab, which investigates neural circuitry to prevent Alzheimer’s disease-related memory impairments. There are currently 7 million Americans living with Alzheimer’s, a number that is expected to increase to 13 million by 2050.
“My grandmother has Alzheimer’s, and it is my regret that, for all the years I and others have tried to find a cure, there isn’t one yet. So I really want to contribute as much as I can to help.”
- Kei Igarashi, UC Irvine Chancellor’s Fellow and associate professor of anatomy and neurobiology
To find out more about the science between smell and memory and discover how researchers are stimulating cognitive reserve, read the full story.
UC Irvine Magazine is produced by the Office of Strategic Communications & Public Affairs.
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