Evaluation of the Effects of Etifoxine 100 mg and Lorazepam 2 mg on Vigilance and Cognitive Functions in the Elderly

Inclusion Criteria: * Man or woman aged from 65 to 75 years * Right-handed subject (Edinburgh Handedness inventory) * Subject having signed the consent form * Subject having agreed to be listed on the French National Healthy Volunteers database * Subject affiliated or beneficiary to French social insurance Exclusion Criteria: * Subject presenting a neurological or psychiatric disease notably cognitive, progressing * Anxious subject (Hamilton score \> 7 and/or Spielberger score \> 51 for a man or \> 61 for a woman) * Left-handed subject (Edinburgh Handedness inventory) * Subject presenting a not corrected visual disease or a motor function disease that could interfere with tests realization * Smoker * Subject taking one or more psychotropics or apparent products * Subject having taken, during the previous month, one or more drugs that could interfere with study drugs metabolism * Subject drinking too much coffee or tea (\> 4 cups per day) or alcohol (\>½ liter of wine or equivalent per day) * Subject presenting contra-indication to one of the drugs used in the study * Subject with past history of intolerance to drugs used in the study * Subject not capable to use the CANTAB cognitive evaluation system * Subject which may not be able to participate to the whole study * Subject under tutelage or guardianship * Subject not able to well-understand French and so to understand cognitive tests * Subject not capable to swallow capsules * Subject participating to another study or in exclusion period (3 months after a previous trial).