Brain Signals and Breathing Become Unsynchronized During Deep Sleep

When sleep is still light, brain activity appears as slow waves whose rhythms remain synchronized with breathing.

A recent study has revealed a unique phenomenon in which brain signals and human breathing patterns stop moving in sync during deep sleep. This occurs because signals from the brain weaken significantly within motor networks as a person enters deeper stages of sleep.

However, this lack of synchronization between breathing and brain signals does not occur during light sleep. According to researchers, when sleep is not yet deep, brain activity still appears as slow waves whose rhythm aligns with breathing patterns.

“Understanding why the brain releases this timing signal may help explain how deep sleep reshapes communication between internal circuits and the body,” said Bon-Mi Gu, a researcher from Hackensack Meridian Health, as reported by Earth.com on March 8, 2026.

Researchers believe that this phenomenon—where breathing and brain signals become unsynchronized—plays an important biological role in body recovery. It may also allow the brain to perform specific functions, such as long-term memory consolidation and removal of metabolic waste through the lymphatic system, without interference from the physical rhythm of breathing.

In the study published in The Journal of Neuroscience, researchers explained that the brain signals originate from deep brain regions related to movement control and the motor cortex. By demonstrating that deep sleep can disconnect the timing relationship between breathing and major motor circuits, the study provides a new perspective on the fundamental relationship between the brain and the body.