What is the opponent-process theory of emotion and how does it explain the contrasting emotional experiences that individuals may have when faced with different stimuli or situations?

The opponent-process theory of emotion suggests that emotions come in pairs, with one emotion being followed by its opposite. For example, feeling fear may be followed by relief. This theory explains how individuals may experience contrasting emotions when faced with different stimuli or situations, as the initial emotion triggers a subsequent opposite emotion to maintain emotional balance.