When dreaming during Rapid Eye Movement (REM) sleep, we can perform complex motor behaviors while remaining, in reality, motionless. How the motor cortex behaves during this state remains unknown. Here, using intracerebral electrodes sampling the human motor cortex in pharmaco-resistant epileptic patients, we report a pattern of EEG activation during REM sleep similar to that observed when performing a voluntary movement during wakefulness. This pattern is present during phasic-REM sleep but not during tonic-REM sleep, the latter resembling relaxed wakefulness. This finding may help clarify certain phenomenological aspects observed in REM-sleep behavior disorder. This article is protected by copyright. All rights reserved.