In our efforts to de-clutter our busy minds and stop thinking about something to make room for new, often more effective thoughts, people tap an array of unique strategies. Which works well, and how can each strategy distinctly affect the brain?
“Let it go” “Think about something else.” “Clear your mind.”
Researchers at the University of Colorado Boulder and the University Of Texas have taken a first stab at answering this question, combining novel brain imaging together with machine learning methods to supply an unprecedented window into what happens in the mind when we attempt to stop thinking about something.
The findings, released this month in the journal Nature Communications, lend new insight into the basic building blocks of cognition and may inform new treatments for issues like post-traumatic stress disorder and obsessive compulsive disorder. They also provide hints on how to form better study habits or innovate at work.
“We found that if you really want a new idea to come into your mind, you need to deliberately force yourself to stop thinking about the old one,” said co-author Marie Banich, a professor of psychology and neuroscience at CU Boulder.
For the study, Banich teamed up with Jarrod Lewis-Peacock, a cognitive neuroscience in UT-Austin, to analyze brain activity from 60 volunteers as they attempted to stop thinking about something in their working memory.
As Lewis-Peacock describes it, working memory is the “scratch pad” of the mind where we keep ideas temporarily to help us carry out jobs. But we could only keep three or four ideas in working memory at one time. Like a sink full of dirty dishes, it has to be cleaned out to create new ideas potential.
“Once we’re done using that information to answer an email or address some problem, we need to let it go so it doesn’t clog up our mental resources to do the next thing,” he said.
When we ruminate over some thing – possibly the argument we had with a friend or a offending text that can color new ideas in a negative light. Such rumination is at the root of several mental health ailments, said Banich.
“In obsessive compulsive disorder it could be the thought of as, ‘If I don’t wash my hands again I will get sick.’ In anxiety, it might be, ‘This plane is going to crash.'” To determine if they can actually stop thinking about something, and , the team asked each volunteer to lay down within a functional magnetic resonance imaging machine (fMRI) at the Intermountain Neuroimaging Center on the Boulder campus.
They were shown pictures of faces, fruits and scenes and requested to maintain the thought of these for 4 seconds. Meanwhile, researchers created individualized ‘brain signatures’ showing exactly what every individual’s brain seemed like when they thought of every image.
Afterward, participants were advised to: replace the idea (“replace Apple mountain”); apparent all thoughts (comparable to mindfulness meditation); or suppress the thought (concentrate on it and deliberately try to quit considering it). In every scenario, the mind touch connected to the picture clearly faded.
“The bottom line is: If you want to get something out of your mind quickly use ‘clear’ or ‘replace,'” said Banich. “But if you want to get something out of your mind so you can put in new information, ‘suppress’ works best.”
The researchers also found that “replace,” “clear” and”suppress” had quite different consequences.
While ‘replace’ and ‘clear’ prompted the brain image to fade faster, it did not fade entirely, leaving a shadow in the background as fresh thoughts were introduced. ‘Suppress,’ on the other hand, took longer to prompt forgetting but was more complete in creating space for a new thought.
Behavioral studies away from the scanner yielded similar results.
“The bottom line is: If you want to get something out of your mind quickly use ‘clear’ or ‘replace,'” said Banich. “But if you want to get something out of your mind so you can put in new information, ‘suppress’ works best.”
More research is necessary, but the findings suggest that students may want to pack up their algebra notes, take a break and deliberately try to stop thinking about quadratic equations before continuing on to study for math.
Hit a wall on that report on the job? Stop thinking about it.
“People often think, ‘If I think about this harder I am going to solve this problem.’ But work by clinicians suggests it can actually give you tunnel vision and keep you in a loop that is hard to get out of,” said Banich.
In a counseling setting, the findings indicate that to completely stop thinking about something which keeps bubbling up, one might want to intentionally concentrate on it and push it off.
Someday, the brain imaging method could be utilized during sessions as a type of cognitive mirror to help people understand how to stop thinking about something.
Banich and Lewis-Peacock wish to study that next.
“If we can get a sense of what their brain should look like if they are successfully suppressing a thought, then we can navigate them to a more effective strategy for doing that,” said Lewis-Peacock. “It’s an exciting next step.”
Related Journal Article: https://www.nature.com/articles/s41467-020-20085-4