A method operates a hearing system which has a hearing instrument worn in an ear. The method includes capturing a sound signal from an environment, processing the captured sound signal in dependence of a set of signal processing parameters, and outputting a processed sound signal to the user. The method further includes analyzing the captured sound signal to recognize own-voice intervals, in which the user speaks, analyzing the captured sound signal for an acoustic feature of the own voice of the user and/or analyzing a signal of a bio sensor. The bio sensor measures at least one non-acoustic vital function of the user and determines, from the acoustic feature and/or the non-acoustic vital function of the user, a measure of an emotional state of the user. A value of a signal processing parameter is adapted, within the own-voice intervals, to change the emotional state if a criterion is fulfilled.