A thought experiment, sometimes referred to as the “don’t think of a polar bear” game, is simple: you’re told to not think of a polar bear and then you do your best to follow that instruction.
Anyone who has attempted this task knows that it’s borderline impossible to not think about something you’ve been instructed to not think about, and that’s the point of the experiment: to demonstrate a concept called Ironic Process Theory, or sometimes Ironic Rebound, for short.
The irony in those monickers is that the more we try to suppress a thought, the more that thought will tend to bubble up into our consciousness, no matter how mightily we struggle to set it aside.
This concept was initially formally studied in the mid-1980s by a social psychologist who was keen to learn more about our capacity to control our thoughts, and to identify and understand methods that might give us more capacity in this regard, using Freud’s theories on the unconscious as a primer.
The original experiment involved telling participants not to think of a white bear, and they were instructed to ring a bell every time they thought about one, anyway, the order of the tasks they performed the only difference between the two groups into which they were divided.
A third group was later added, and these participants were told to think of a red Volkswagen while not thinking of a white bear, which seemed to help substantially: they rang the bell a lot less frequently than the other two groups that didn’t benefit from that distraction instruction.
There’s some contention as to whether these results are generalizable to non-white-bear thoughts, but some research suggests that attempts to (for instance) suppress emotions, addictive urges, pain, or other things we might want to muffle or temper or numb can instead cause those things to become nearly un-ignorable—our brains in some cases shifting away from them temporarily, but then more likely to re-notice them if exposed to any stimuli even tangentially associated with that “currently being suppressed” concept, which in turn can cause our brains to become preoccupied with these veiled ideas.
This understanding, though incomplete, has been successfully applied to treatments for folks who suffer from suicidal ideation, depression, and anxiety, as those who experience such thoughts might try to suppress them, which can then root them in such a way that they keep popping up and over time become incredibly difficult to dislodge.
Instead, many therapists encourage their patients to accept these feelings and focuses rather than avoiding them, which seems to in some cases prevent that ironic rebound amplification effect.
Refocusing on other things rather than suppressing unwanted thoughts or fixations, too, may help, as distractions from otherwise preoccupying thoughts or sensations can increase our mental load, leaving us with less cognitive processing power to invest in that thing we might otherwise latch onto, and that at times can help normalize it, allowing us to deal with it more productively and at less of a disadvantage from that point forward.