A recent study found that an imagery-competing task intervention reduced the frequency of intrusive memories in healthcare workers during the COVID-19 pandemic. The intervention involved recalling an intrusive memory and then playing Tetris for 20 minutes. The study was published in BMC Medicine.
Intrusive memories are unwanted, involuntary recollections of distressing events that suddenly enter a person’s mind. They typically arise from traumatic experiences and tend to be vivid, emotionally intense, and difficult to control. These memories can be triggered by reminders of the original event or may appear without any obvious cause.
They are especially common in individuals with post-traumatic stress disorder. Intrusive memories may involve visual images, sounds, or even bodily sensations from the traumatic event. They can interfere with concentration, sleep, and daily functioning. Unlike ordinary memories, intrusive memories often feel as if the event is happening again in the present moment and are typically accompanied by strong emotions such as fear, shame, or helplessness.
Study author Marie Kanstrup and her colleagues aimed to test the effectiveness of a brief imagery-competing task intervention in reducing intrusive memories among healthcare workers in Sweden who were exposed to work-related trauma during the COVID-19 pandemic (2020–2022). They hypothesized that participants who received the intervention would report fewer intrusive memories five weeks later, compared to those in a control group.
The study included 144 Swedish healthcare workers who were active during the pandemic. A total of 130 participants completed the full study. Of these, 82% were women, 71% were employed full-time, and 58% worked as nurses. The average participant age was 41 years.
Participants were randomly assigned to one of two groups. Both groups were told they would be completing a cognitive task. One group received the imagery-competing task, while the other listened to a podcast and answered brief quizzes about it. In the imagery-competing task, participants were instructed to recall one of their intrusive memories and then play the video game Tetris on their smartphones for 20 minutes. They were also encouraged to repeat the intervention later on their own to target additional intrusive memories.
Both interventions were delivered via smartphone and took approximately 25 minutes to complete. Participants kept a daily diary for five weeks, recording the number of intrusive memories they experienced each day. They also completed assessments measuring post-traumatic stress symptoms and other psychological variables.
The results showed that the imagery-competing task significantly reduced the frequency of intrusive memories compared to the control condition. It also led to fewer post-traumatic stress symptoms at one, three, and six months after the intervention.
“In summary, healthcare workers were exposed to work-related trauma during the pandemic. We observed the need for brief, flexible, remotely delivered, and repeatable interventions as an urgent public health priority, including a subclinical-to-clinical sample for a preventing-to-treating approach. This study provided controlled evidence that this population benefited from the single guided session, digitally delivered imagery-competing task intervention to reduce intrusive memories after trauma,” the authors concluded.
The study offers insight into how an imagery-competing task can affect intrusive memories. However, it is important to note that participants were exclusively healthcare workers, and the intrusive memories they reported were likely related to vicarious trauma—that is, witnessing the suffering of others. The results may not generalize to individuals who have directly experienced traumatic events themselves.
The paper, “A guided single session intervention to reduce intrusive memories of work-related trauma: a randomised controlled trial with healthcare workers in the COVID-19 pandemic,” was authored by Marie Kanstrup, Laura Singh, Elisabeth Johanna Leehr, Katarina E. Göransson, Sara Ahmed Pihlgren, Lalitha Iyadurai, Oili Dahl, Ann‑Charlotte Falk, Veronica Lindström, Nermin Hadziosmanovic, Katja Gabrysch, Michelle L. Moulds, and Emily A. Holmes.
