Yoga and meditation were found to improve verbal and visual-spatial memory for older adults.
The study was led by researchers from the University of California-Los Angeles (UCLA), including senior author Dr. Helen Lavretsky, of the Department of Psychiatry.
Mild cognitive impairment (MCI) is characterized by noticeable changes in cognitive function, such as the development of memory and thinking problems.
Though these changes are not severe enough to interfere with a person's independence and day-to-day activities, symptoms can worsen with time, increasing the risk of Alzheimer's disease and other dementias.
According to the Alzheimer's Association, long-term studies indicate that around 10-20 percent of adults aged 65 and older are likely to have MCI.
Of these adults, it is estimated that around 6-15 percent develop dementia each year.
While there are currently no approved medications to treat MCI, experts recommend that older adults with the condition engage in mentally stimulating activities - such as crossword puzzles - in order to reduce their risk of dementia.
Now, Dr. Lavretsky and colleagues say practicing yoga and meditation may be just as effective - if not better - for protecting cognitive function.
Yoga vs. memory enhancement training for cognitive function
For their study, the researchers enrolled 25 participants aged 55 and older.
For 12 weeks, 14 of the participants took part in a 1-hour Kundalini yoga class once a week and practiced Kirtan Kriya meditation for 20 minutes every day.
Kundalini yoga is referred to as the "yoga of awareness," incorporating breathing techniques, meditation, and chanting.
Kirtan Kriya meditation involves chanting, hand movements, and light visualization. Dr. Lavretsky notes that this form of meditation has been practiced in India for hundreds of years as a way to maintain cognitive function in older adults.
The remaining 11 participants engaged in 1 hour of memory enhancement training - through activities such as crossword puzzles or computer games - once a week for 12 weeks, and they also spent 20 minutes a day completing memory exercises.
At the beginning and end of the 12-week study period, all participants completed memory tests and underwent functional magnetic resonance imaging (fMRI), enabling the researchers to assess their cognitive function and brain activity.
Visual-spatial memory improvements greater for yoga-meditation group
The team found that both groups showed improvements in verbal memory skills - the ability to remember names and lists of words - at the end of the 12 weeks.
Fast facts about yoga
- Around 21 million adults in the United States practice yoga
- Yoga use in the U.S. increased from 5.1 percent in 2002 to 6.1 percent in 2007
- Studies have suggested yoga can reduce stress and chronic pain.
However, the participants who practiced yoga and meditation demonstrated greater improvements in visual-spatial memory skills - the ability to navigate and remember locations - than those who engaged in memory enhancement training.
The team says the latter finding is particularly relevant for people who experience MCI, as the condition can be emotionally difficult to come to terms with.
"When you have memory loss, you can get quite anxious about that and it can lead to depression," notes Dr. Lavretsky.
On assessing participants' brain activity, the researchers found that improvements in verbal memory and visual-spatial memory correlated with changes in brain connectivity.
However, they found that only the yoga-meditation group demonstrated brain connectivity changes that were statistically significant.
The team suggests that the improvements in memory, mood, and stress resilience seen with yoga and meditation may be down to the increased production of a protein called brain-derived neurotrophic growth factor (BDNF).
BDNF is responsible for boosting connections between brain cells, as well as maintaining the survival of existing brain cell connections.
Overall, the researchers believe their findings indicate that yoga and meditation may be an effective strategy for protecting against cognitive decline in older adults.
"If you or your relatives are trying to improve your memory or offset the risk for developing memory loss or dementia, a regular practice of yoga and meditation could be a simple, safe and low-cost solution to improving your brain fitness."
Dr. Helen Lavretsky