REM Sleep Metabolism and Hormone Regulation Uncovered in New Brain Studies

Researchers at Tohoku University in Japan reported that during REM sleep the brain’s blood volume rises without a corresponding increase in available energy for neurons, revealing a metabolic paradox. Using a novel imaging technique that visualizes blood flow, astrocyte metabolism and neuronal ATP in mice through an intact skull, the team measured three key indicators and published the findings in Communications Biology.

A separate study by scientists at the University of California, Berkeley mapped a hypothalamic circuit that controls growth‑hormone release during sleep. The research identified two opposing groups of neurons that act as a “gas” and a “brake” to regulate hormone secretion in REM versus deep non‑REM sleep. Published in Cell, the work links sleep patterns to metabolic health, obesity, diabetes, cardiovascular risk and neurodegenerative diseases such as Alzheimer’s and Parkinson’s.