A method comprising receiving, from a circuit, information indicative of a skin resistance between an inner electrode and an outer electrode, the inner electrode being disposed on at least part of an inner surface of a housing, the outer electrode being disposed on at least part of an outer surface of the housing such that the outer electrode is separated from the inner electrode, the housing being configured to be in contact with or at least partially encircle a body part of a user of the housing, such that the inner surface of the housing is configured to at least partially contact the body part and the outer surface of the housing is configured to avoid contact with the body part, and determining a galvanic skin response of the user based, at least in part, on the skin resistance when the outer electrode is in contact with the user.