Rock-a-bye, baby — or insomniac adult.
Those who struggle to fall or stay asleep have most likely tried every trick in the book to catch some Z’s, from cutting back on caffeine to popping melatonin.
Recent research, though, suggests one modification could offer a better night’s rest, and it’s something babies experience on the regular.
Nearly one in five US adults struggle to stay asleep, turning a necessity for health into a waking nightmare of daytime fatigue, trouble focusing and chronic illness.
A small study published in the Journal of Sleep Research may have found an unexpected solution: rocking adults to sleep.
Continuous, slow rocking was found to reduce nighttime awakenings and improve overall sleep quality in 16 adults with insomnia symptoms.
The researchers behind the study wanted to know if physical movement could influence brain rhythms during sleep, particularly during deep sleep.
To test the theory, the team recruited 16 adults who dealt with insomnia to spend one night on a stationary bed, then the following night on a bed that moved from side to side in a slow, continuous rocking motion.
Participants’ brain waves, muscle activity and eye movement were measured throughout both nights, and a memory test was also administered before going to sleep and after waking up.
Compared to the stationary night, the participants spent 34% less time awake in the middle of the night, as well as about 15% less time in the lightest and most easily interrupted stage of sleep.
The participants also said their sleep quality improved, noting a 25% increase in a questionnaire on sleep experience.
When we’re asleep, we progress through various stages, going from light sleep to deep sleep and eventually rapid eye movement (REM) sleep.
Deep sleep is defined by specific electrical activity patterns in the brain, most notably slow oscillations that are large, rolling waves interspersed with brief, rapid bursts of electrical activity known as sleep spindles.
These rhythms are believed to block out environmental noise and help the brain process events of the day.
Previous research by the same team found that healthy sleepers spend more time in deep sleep and have enhanced memory recall after sleeping on a rocking bed.
Meanwhile, other studies in mice show this effect is caused by a sensory network in the inner ear that detects movement and balance, or the vestibular system.
The vestibular system sends a rhythmic signal to the thalamus, a brain region central to generating sleep spindles and slow waves, when a person is gently rocked.
The team also found that the side-to-side motion synced up with the brain’s natural rhythms and electrical activity, with sleep spindle bursts and the lowest points of slow wave activity matching the physical movements of the bed.
While the rocking bed did enhance deep sleep, it didn’t improve the amount of time it took participants’ to fall asleep, a hallmark trait of insomnia.
The improved deep rest also didn’t affect cognitive function, as a word-pair memory test showed similar results after both a night in a stationary bed and a rocking one.
