Opponent Process Theory is a psychological concept that explains how emotions and sensations are experienced in pairs of opposites. When one emotion is triggered, the opposite emotion is suppressed. For example, if a person feels intense pleasure from a thrilling experience, they may later feel discomfort or sadness as the initial excitement fades. This theory helps to understand how people adapt to emotional experiences over time. The theory was proposed by Richard Solomon in the 1970s and is often applied to various fields, including psychology, addiction, and motivation. It suggests that repeated exposure to a stimulus can lead to a decrease in the initial emotional response and an increase in the opposing response, influencing behavior and emotional regulation.