Sweet smells may boost memory

UF Health Podcasts

Smell and memory have long seemed inextricably linked. It’s more than the way a certain aroma can trigger a strong, long-ago memory.

Dementia, Alzheimer’s, and other disorders involving the brain are often preceded by a loss of olfactory capacity. Scientists, for example, are today studying how the loss of the sense of smell with COVID-19 infection might be associated with reports of cognitive impairment from the coronavirus.

Could that connection be used therapeutically?

A study by University of California researchers says evidence shows it likely could be. Every night for two months, they wafted a fragrance through the bedrooms of older adults without cognitive impairment and found aromas had a dramatic impact on memory.

They saw a 226% increase in cognitive capacity, or memory, for those ages 60 to 85 who slept while a strong fragrance was pumped into their bedrooms. That’s compared with a control group exposed to weaker fragrances.

Imaging showed those with improved memory had stronger integrity in a brain pathway between the medial temporal lobe and the decision-making prefrontal cortex. This pathway often weakens as we grow older.

As one researcher notes, when our eyesight deteriorates as we grow older, we can get a prescription for new eyeglasses. Memory impairment, however, resists any easy fix.

While the study is relatively small and involved just 43 participants, the scientists believe it points to the possibility of developing aroma therapy to treat cognitive decline.

“Stop and smell the roses” might become more than a cliché. It could one day be doctor’s orders.