A gentle rocking motion, similar to that used to soothe infants, may help adults with insomnia achieve better sleep, according to a small study published in the Journal of Sleep Research. The research indicates that continuous, slow rocking can reduce the number of times individuals wake up during the night and enhance their overall sleep quality.
Nearly one in five adults in the U.S. experience difficulty sleeping, which can lead to daytime fatigue, concentration problems, and chronic health issues. This study explored whether physical movement could influence brain rhythms during sleep, particularly during deep sleep stages.
Researchers recruited 16 adults who reported symptoms of insomnia. Participants spent one night sleeping on a stationary bed and the following night on a bed that moved from side to side with a slow, continuous rocking motion. Throughout both nights, their brain waves, muscle activity, and eye movements were monitored. Participants also completed a memory test before sleeping and after waking.
Compared to the night spent on the stationary bed, participants on the rocking bed spent 34% less time awake during the night and approximately 15% less time in the lightest sleep stage, which is more easily disrupted. Participants also reported a 25% improvement in their subjective sleep quality.
Understanding Sleep Stages and Rocking
Sleep progresses through various stages, including light sleep, deep sleep, and rapid eye movement (REM) sleep. Deep sleep is characterized by specific electrical activity in the brain, featuring slow oscillations and brief bursts of electrical activity known as sleep spindles. These rhythms are believed to help block out external noise and facilitate the processing of daily experiences.
Previous research by the same team suggested that healthy sleepers experience more deep sleep and improved memory recall when sleeping on a rocking bed. Studies in mice indicate that this effect may be linked to the vestibular system, located in the inner ear, which detects movement and balance. When a person is rocked gently, the vestibular system sends rhythmic signals to the thalamus, a brain region crucial for generating sleep spindles and slow waves.
The study observed that the side-to-side motion of the bed synchronized with the brain's natural rhythms. Specifically, the bursts of sleep spindles and the lowest points of slow wave activity coincided with the physical movements of the bed.
Despite the positive effects on deep sleep and overall quality, the rocking bed did not reduce the time it took for participants to fall asleep, which is a key characteristic of insomnia. Furthermore, the enhanced deep sleep did not significantly improve cognitive function, as measured by a word-pair memory test, which yielded similar results after both stationary and rocking bed nights.