The dreaming brain surges with energy, yet its neurons may consume it faster than they can replenish it. A new mouse study from Tohoku University has uncovered a surprising energy imbalance during rapid eye movement (REM) sleep. How REM Sleep Supports Brain EfficiencyRather than distributing energy evenly, the brain may redirect resources according to its current needs. “REM sleep gives us a natural example of how the brain reorganizes its energy economy to support complex internal processing.” Reference: “Energy paradox in REM sleep: balancing supply and consumption in brain metabolism” by Yusuke Takahashi, Yoko Ikoma and Ko Matsui, 27 July 2026, Communications Biology.