Inclusion Criteria:  be a group leader in an infantry regiment, be over 18 years old.  Exclusion Criteria:  be a woman, have a heart condition, have a visual disease not corrected by glasses or contact lenses, have a hearing score ≥ 2 on the SIGYCOP, have a psychiatric disorder, a progressive neurological or organic disease requiring drug treatment, take psychotropic drugs, take more than 28 units of alcohol per week.