The day before surgery, patients sign the consent and will be randomized. Then 3 tests (Stroop test, Digit Symbol Substitution Task and visual verbal learning test) will be performed. No anxiolysis will be given to the patient. The anesthetic induction will be with IV propofol (2-3 mg / kg). The maintenance will anesthetic, desflurane by for a minimum alveolar concentration of between 2% and 6% or propofol for intravenous anesthesia user target controlled. In SSPI, the Aldrete score will be evaluated every 5min. Upon obtaining a Aldrete score> 8/10, the day before the tests will be carried out again