In a global study, scientists from the Medical Research Council (MRC) Cognition and Brain Sciences Unit taught 120 volunteers how to control distressing thoughts about adverse events. Surprisingly, these thoughts became less intense, and the participants’ mental well-being improved remarkably.
Professor Michael Anderson said, “We’re all familiar with the Freudian idea that if we suppress our feelings or thoughts, then these thoughts remain in our unconscious, influencing our behavior and well-being perniciously.”
“The whole point of psychotherapy is to dredge up these thoughts so one can deal with them and rob them of their power. In recent years, we’ve been told that suppressing thoughts is intrinsically ineffective and causes people to think the thought more – it’s the classic idea of ‘Don’t think about a pink elephant.” he added.
“These ideas, once widely accepted in clinical treatment, have become established beliefs,” explained Professor Anderson. National guidelines often emphasize eliminating and overcoming thought avoidance as a harmful coping mechanism, particularly in conditions like depression, anxiety, and PTSD.
When the COVID-19 pandemic emerged in 2020, Professor Anderson, like many researchers at University of Cambridge, sought ways to apply his research to help people during the crisis. He focused on a brain function called inhibitory control, which allows us to override automatic responses. He was particularly interested in how this function could manage memory retrieval, especially in preventing the recall of negative thoughts when faced with powerful reminders.
Dr. Zulkayda Mamat, a former Ph.D. student in Professor Anderson’s lab and Trinity College, Cambridge, was intrigued by the role of inhibitory control in overcoming trauma, both in her own life and in the experiences of others. She wanted to investigate whether this ability was innate or learned and whether it could be taught.
Dr Mamat said: “Because of the pandemic, we saw a need in the community to help people cope with surging anxiety. There was already a mental health crisis, a hidden epidemic of mental health problems, worsening. So with that backdrop, we decided to see if we could help people cope better.”
Professor Anderson and Dr. Mamat conducted a study involving 120 participants from 16 different countries to explore whether people could benefit from practicing the suppression of their fearful thoughts. Their findings have been published in Science Advances.
In the study, each participant had to think about various scenarios that could happen in their lives over the next two years. This included 20 negative “fears and worries,” 20 optimistic “hopes and dreams,” and 36 routine, everyday events. These fears were worries that bothered them and kept intruding into their thoughts.
For each scenario, they had to provide a cue word (a clear reminder) and a key detail (a single word describing an essential aspect of the event). For example:
- Harmful: Visiting parents in the hospital due to COVID-19, with the cue ‘Hospital’ and the detail ‘Breathing.’
- Neutral: Going to the optician, with the cue ‘Optician’ and the detail ‘Cambridge.’
- Positive: Witnessing their sister’s wedding, with the cue ‘Wedding’ and the detail ‘Dress.’
Participants rated each event on various factors, such as how vividly they could imagine it, how likely it was to happen, how far in the future it was, how anxious (or joyful) it made them feel, how often they thought about it, and more. They also completed mental health questionnaires with participants of various mental health backgrounds, including those with depression, anxiety, and pandemic-related post-traumatic stress.
Then, Dr. Mamat guided each participant through a 20-minute training session over Zoom. This training involved repeating both “No-imagine” and “Imagine” instructions for events, with 12 repetitions each, every day for three days.
In this study, participants were divided into two groups: one group had to suppress their negative thoughts, and the other had to stop neutral ideas. They were given cue words related to these thoughts.
For the “No-imagine” trials, participants with negative thoughts had to acknowledge the idea but then block it out. They could not imagine the event or use other views to distract themselves. The goal was to prevent any images or thoughts related to the event from coming up. Participants with neutral ideas followed the same process.
In the “Imagine” trials, participants were asked to vividly imagine positive or neutral events. However, they were not asked to imagine adverse events for ethical reasons.
After three days of training and again three months later, participants had to rate these thoughts’ vividness, anxiety levels, and emotional intensity. They also completed questionnaires about their mental health, including depression, anxiety, worry, and well-being.
Dr. Mamat noted that participants who practiced suppressing their fearful thoughts reported that these thoughts became less vivid and less anxiety-inducing. Overall, their mental health improved. This improvement was most significant in participants who practiced suppressing negative thoughts.
Even participants with likely post-traumatic stress disorder benefited from thought suppression. Those who suppressed negative thoughts saw a significant improvement in their mental health, with a 16% reduction in negative mental health scores and a nearly 10% increase in positive mental health scores. This contradicted the belief that thought suppression is harmful.
Individuals with more severe mental health symptoms at the start of the study experienced more significant improvements, significantly if they were suppressing negative thoughts.
Contrary to common beliefs, suppressing negative thoughts didn’t make them come back more vividly in most participants. Only one out of 120 people remembered stopped thoughts more clearly after training. A few reported increased vividness for specific ideas, which was no different from the rate of vividness changes in thoughts they hadn’t suppressed.
Professor Anderson said, “This challenges the usual thinking. Actively suppressing fearful thoughts may be beneficial.”
After the study, participants weren’t asked to keep practicing, but many continued to do so independently. When researchers checked in three months later, they found that the benefits, like reduced depression and negative emotions, continued for everyone. Those who kept using the technique daily saw the most significant improvements.
One participant even taught her daughter and mother how to do it because she found it helpful. Another person said the study came at the perfect time during the COVID-19 pandemic when they felt isolated and anxious about the future.
In conclusion, this study challenges the belief that suppressing negative thoughts harms mental health. Actively suppressing fearful thoughts may be both possible and beneficial, reducing depression and negative emotions without causing a rebound effect. Many participants continued using the technique daily, suggesting its sustained benefits. This research opens new possibilities for using thought suppression to enhance mental well-being.
Journal Reference:
- Zulkayda Mamat, Michael C. Anderson. Improving mental health by training the suppression of unwanted thoughts. Science Advances. DOI:10.1126/sciadv.adh5292.