Cortical Excitability and Decision Making After Total Sleep Deprivation and Sleep Restriction

The investigators examine changes in decision making, vigilance and cortical excitability in healthy male subjects undergoing total acute sleep deprivation (40 hours) on the one hand, and chronic partial sleep restriction (7 nights with 5 instead of 8 hours in bed per night) on the other hand, in a cross over controlled manner. The investigators hypothesize that total sleep deprivation, as well as partial sleep restriction lead to impairments in decision making and vigilance, and enhanced cortical excitability. Beside these three primary outcomes, the investigators also assess changes in sleep by EEG, dim light melatonin onset, skin temperature, subjective mood and sleepiness, working memory, and also collect saliva samples.