Sleep slow-wave activity predicts changes in human cortical excitability during extended wakefulness

摘要: Objective Slow-wave activity (SWA: 0.75-4.0 Hz) is a classical hallmark of sleep homeostasis. It is associated to synaptic downscaling, leading to a gradual decrease of cortical excitability during sleep. Here we investigated whether SWA predicts subsequent human cortical excitability during extended wakefulness. Methods After 8h nocturnal sleep, 19 healthy young men (18-30y) followed a 28h sleep deprivation protocol under constant routine conditions, during which they underwent 8 EEG recordings of transcranial magnetic stimulation (TMS)-evoked potentials. Sleep was scored using AASM criteria, and power spectra were calculated. Cortical excitability was inferred from the amplitude of the first component of TMS-evoked potentials over prefrontal cortex. A linear regression between frontal SWA (upper asymptote during first NREM sleep cycle) and cortical excitability was computed. Results Analyses reveal a …