Dr's Casebook: Aromas while sleeping can help to improve memory and cognitive function

Dr Keith Souter writes: If you have read the novel Hamnet by Maggie O’Farrell you’ll know that Anne Hathaway was William Shakespeare’s wife. Her cottage garden has a huge orchard full of apple trees of numerous varieties.

The apple harvest is sent away to be turned into apple juice and cider to sell in the cottage shop.

Many apples had fallen and bruised or been half-eaten by wasps.

The result was that as I was up the trees the almost intoxicating scent of apples surrounded me and brought back many memories of long ago.

Various aromas can all trigger memory function.

This is well known anecdotally, in that most of us can relate to having had memories triggered by certain scents.

A piece of research just reported from the University of California has looked at this to see if it can not only trigger memory function, but also help with cognitive function.

The researchers found that when a fragrance wafted through the bedrooms of older adults for two hours every night for six months, memory function increased dramatically.

Indeed, participants in the study more than doubled their cognitive capacity compared to the control group.

They conducted the trial on men and women aged 60 to 85 years of age, none of whom had existent memory impairment.

All were given a diffuser and seven cartridges, each containing a single and different natural oil.

Half of them received full-strength cartridges while the other half who acted as a control group were given the oils in tiny amounts.

They all put a different cartridge into their diffuser each evening prior to going to bed, and it wafted through their bedroom for two hours as they slept.

Everyone had a standard memory test evaluation and also had brain imaging performed after the six months.

Not only did the high strength group have more than two and a quarter improvement in function than the control group, but the imaging showed better integrity in the brain pathway called the left uncinate fasciculus, which was regarded as highly significant.

They concluded that these findings provide a simple technique that could be used to strengthen memory and potentially stave off dementia.