The investigators have chosen for a trial design in which sugammadex will be used to reverse the neuromuscular blockade induced by rocuronium. Sugammadex in the first, neostigmine/glycopyrrolate in the second, and placebo in the third study arm, will be administered post surgery when clinical neuromuscular function has recovered to the level of TOF ratio ~ 0,9 (i.e. when 70-80% of the receptors are still occupied). It is supposed that sugammadex will efficiently and quickly reverse this "subclinical" rest blockade, leading to an increased alertness. Since a higher alertness has never been described from the traditional drug neostigmine or from placebo is it not expected that they have such an effect. The post surgery cognitive evaluations will be performed 30 minutes after this TOF ratio has been reached. This first 30 minutes time point is considered clinically relevant. In case an effect can only be demonstrated later, the relevance becomes questionable. TOF will only be measured until it reaches approximately 0.9, thereafter only cognitive functions will be evaluated.