People who regularly practice advanced meditation techniques may have brains that appear biologically younger than their actual chronological age. By measuring brain electrical activity during sleep, the researchers found that long-term meditators showed brain activity patterns typical of people nearly six years younger. These measurements were recently published in the journal Mindfulness.
As humans age, sleep changes in predictable ways. Older adults typically experience shorter, more fragmented rest periods with fewer deep sleep stages. At the level of the brain’s electrical activity, aging is associated with a decline in slow brain waves and sleep spindles, which are short bursts of high-frequency brain activity that help consolidate memories.
Scientists can use these natural age-related changes to calculate biological brain age. They compare an individual’s sleep brain waves to established age norms. When a person’s biological brain age is older than their years of life, they are at increased risk of cognitive decline, dementia, and death. Lower estimates are associated with better general health.
Previous studies using magnetic resonance imaging have shown that meditation protects the physical structure of the brain from aging. Jamie Banks, a neurology researcher at Massachusetts General Hospital, and a team of colleagues wanted to see if similar protective markers appeared in the brain’s real-time electrical activity. Researchers decided to study brain age in a population of advanced meditation practitioners.
The research team recruited 34 people to participate in a four-day intensive meditation retreat called Samyama Sadhana. This particular retreat requires participants to complete years of prerequisite meditation courses. In the weeks leading up to the retreat, participants must adhere to a vegan diet and practice specific breathing and sitting meditation techniques for several hours each day.
To measure brain activity, study participants wore specialized headbands while sleeping in their own beds. These home devices used electroencephalography, a technology that records electrical signals through sensors placed on the scalp. Meditators wore the headbands several nights in the week before the retreat and several nights in the weeks after the retreat.
The researchers compared the meditators’ sleep data to several large existing sleep record databases. The comparison group included healthy individuals using the same headband at home and a different group of patients visiting a clinical sleep laboratory. These clinical groups ranged from perfectly healthy individuals to patients diagnosed with mild cognitive impairment or severe dementia.
The research team matched meditators and control subjects based on age, gender, race, and education level to ensure like-for-like comparisons. The average age of meditators was 38 years. Sleep data showed that the estimated biological brain age of the meditation group was 5.9 years younger than their chronological age.
In contrast, healthy controls showed a brain age that closely matched their actual chronological age. Groups with known age-related pathology showed much older brain ages. People with mild cognitive impairment had brain ages nearly nine years older than their chronological age, and those with dementia had scores more than 10 years older.
Researchers took a closer look at the specific sleep stages responsible for rejuvenating the brains of meditators. The early estimates were primarily driven by high-amplitude bursts of brain activity during light sleep. These bursts suggest a highly active and organized neural state at rest.
The data also revealed differences in overall sleep amounts. The meditating cohort slept an average of 6.0 hours per night, while the healthy control group slept an average of 7.6 hours. Researchers suggest that advanced meditation practices can improve the quality of your sleep and provide you with a short period of restorative rest.
Alongside sleep monitoring, participants completed a series of standardized emotional and cognitive tests. The results showed that meditators consistently outperformed the national average on tests of fluid cognition, which measures real-time problem-solving skills. They also scored high on certain tests of crystallized cognition, which measure accumulated knowledge, such as reading recall.
Interestingly, the four-day meditation retreat itself did not produce any changes in measured brain age. Sleep recordings taken in the weeks following the retreat showed no measurable reduction in brain age compared to recordings taken beforehand. Cognitive test scores also did not change at all throughout the event.
The retreat affected my mental health. Participants reported increased feelings of positive emotions, emotional support, and camaraderie after the event. They also reported lower perceived levels of daily stress. Researchers suggest that while emotional well-being can change rapidly over a short meditation retreat, physiological changes in the aging brain likely require years of continuous practice.
The biological mechanisms linking meditation to sleep and brain aging are not fully understood. Regular, slow-paced breathing exercises may play a role in altering brainstem activity. A specific group of cells in the brainstem supply norepinephrine to the cerebral cortex, and calming these cells through controlled breathing may encourage the brain to create protective sleep patterns.
This study has several limitations regarding its ability to establish cause and effect. The research team did not have access to baseline sleep data before the participants first started their long-term meditation habits. Lacking this baseline, we cannot claim that meditation directly causes rejuvenation of brain age.
A phenomenon known as self-selection bias may explain this finding. People who are naturally healthy, or who have a lifestyle or genetic predisposition that slows brain aging, may be more likely to pursue an intensive meditation practice in the first place. The study participants were also highly educated, with the majority holding advanced university degrees, another factor known to protect cognitive health.
When the researchers tested whether the number of years a person had been meditating correlated with even younger brain age, the results were not statistically significant. This lack of long-term correlation further weighs down the possibility that innate predispositions may be at play. Future studies that follow beginners over many years are needed to see if meditation positively promotes these changes in brain health.
The study, “Sleep-based brain age is reduced in advanced inner engineering meditators,” was authored by Jamie C. Banks, Sepideh Hariri, Kestutis Kuberaga, Anne Ouyang, Kylie Gallagher, Syed A. Quadri, Ryan A. Tesh, Preity Upadhyay Reid, Robert J. Thomas, M. Brandon Westover, Haoki Sun, and Balachundar. Subramaniam.
