Is it possible to avoid unwanted thoughts?

After a breakup, you might think you're doing fine until you drive past that one street corner, or bump into a mutual friend, or hear a particular love song on the radio. No matter how much you'd like to stop thinking about that person, everything is a reminder of the relationship. Short of erasing whole chunks of your memory, á la Jim Carrey's character in the movie "Eternal Sunshine of the Spotless Mind," is it possible to banish unwanted thoughts? 

The short answer is: maybe. But whether it's advisable to do so in the long term is more complicated. 

People's thoughts are far less focused — and under far less control — than most people imagine, said Joshua Magee, a clinical psychologist and founder of Wellness Path Therapy, who has conducted research on unwanted thoughts, images and urges in mental disorders. In one famous 1996 study in the journal Cognitive interference: Theories, methods, and findings by study author Eric Klinger, a professor emeritus of psychology at the University of Minnesota, participants kept track of all their thoughts over one day. On average, people reported more than 4,000 individual thoughts. And these thoughts were fleeting — lasting no more than five seconds each, on average. 

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"Thoughts are constantly ebbing and flowing, and many of us don't notice," Magee said. In the 1996 study, one-third of these thoughts seemed to pop up totally out of nowhere. It's normal to experience thoughts that feel disturbing, Magee added. In a 1987 study conducted by Klinger and colleagues, people perceived 22% of their thoughts as strange, unacceptable or wrong — for instance, you might imagine yourself chopping off your finger while you're cooking, or dropping your baby as you carry them to their crib. 

In some situations, it makes sense to suppress these unwanted thoughts. In an exam or job interview, for example, you don't want to feel distracted by the thought that you'll fail. On a flight, you probably don't want to think about the plane crashing. And there's evidence that it's possible to quash these thoughts, Magee said. 

In a 2022 study in the journal PLOS Computational Biology, a team of Israeli researchers showed 80 paid volunteers a series of slides displaying different nouns. Each noun was repeated on five different slides. As they viewed the slides, the participants jotted down a word they associated with each noun — for example, "road" in response to the word "car." The researchers told one group that they wouldn't get paid for words they repeated. Another group could repeat as many nouns as they wished. With this method, the researchers sought to emulate what happens when someone hears that love song on the radio and tries desperately to think of anything other than their ex beau. 

The results revealed that when participants saw each noun for a second time, they took longer than the control group to come up with a new association — "tire" instead of "road," for instance — suggesting that their first response popped into their mind before they replaced it. Their responses were particularly delayed for words they rated as "strongly associated" with the cue word the first time around. However, participants got quicker each time they viewed the same slide, indicating that their association between the cue word and their first response — the thought they were trying to avoid — was weakening. 

"We didn't find evidence that people can entirely avoid unwanted thoughts," study lead author Isaac Fradkin, who did the research as a psychologist at the Hebrew University of Jerusalem, told Live Science. But the results suggest that practice can help people get better at avoiding a specific thought, added Fradkin, who is now a fellow at the Max Planck University College London Centre for Computational Psychiatry and Ageing Research.

Not everybody agrees that a slideshow of random words is a good way to tease out how people suppress thoughts laden with emotion, as Medical News Today reported. And other research suggests that avoiding thoughts can backfire. "When we suppress a thought, we're sending our brains a message," Magee said. This effort labels the thought as something to be feared. "In essence, we're making these thoughts more powerful by attempting to control them." A 2020 analysis in the journal Perspectives on Psychological Science of 31 different studies on thought suppression found that thought suppression works — in the short term. While participants tended to succeed at thought-suppression tasks, the avoided thought popped into their head more often after the task was over.

In the end, it might make more sense to take a mindful approach to these unwanted thoughts and simply wait for them to pass rather than avoiding them — just like the thousands of other thoughts that drift through your head each day, Fradkin said. "We can allow these thoughts to just be in our minds, not sort of holding on to them too tightly and not trying to fight them."