Ironic process theory
In psychology, ironic process theory (IPT), also known as the pink elephant paradox or white bear phenomenon, suggests that when an individual intentionally tries to avoid thinking a certain thought or feeling a certain emotion, a paradoxical effect is produced: the attempted avoidance not only fails in its object but in fact causes the thought or emotion to occur more frequently and more intensely. IPT is also known as "ironic rebound," or "the white bear problem." The phenomenon was identified through thought suppression studies in experimental psychology.