A system for operating a hearing instrument (100) is disclosed. The system comprises one or more electrodes (112) for measuring the brain wave signals of a user wearing the hearing instrument (100). The electrodes (112) are placed on the scalp of the user. Based on the measured brain wave signals, a detecting unit (304) is configured to detect a relaxation state of the user. A controller (306) sets the hearing instrument (100) to a relaxation mode setting in response to the detection of the relaxation state of the user.
