When more blood does not mean more neuronal energy during REM sleep

MedicalXpress | авг 02, 2026

REM sleep is already called "paradoxical sleep." The body is largely still, yet the brain is highly active. In humans, this is also the stage most closely associated with vivid dreaming. Our study, published in Communications Biology, has revealed another paradox hidden within REM sleep: Brain blood volume increased, but the ATP available inside neurons decreased.