Single-neuron activity and eye movements during human REM sleep and awake vision

Are rapid eye movements (REMs) in sleep associated with visual-like activity, as during wakefulness? Here we examined single-unit activities and intracranial EEG across the human MTL and neocortex during sleep and wakefulness, and during visual stimulation with fixation. During both sleep and wakefulness, REM onsets are associated with distinct intracranial potentials, reminiscent of PGO waves. Individual neurons, especially in the MTL, exhibit reduced firing rates before REMs as well as transient increases in firing rate immediately after, similar to activity patterns observed upon image presentation during fixation without eye movements. Our results suggest that REMs during sleep rearrange discrete epochs of visual-like processing as during wakefulness.