[Image Source: Wikimedia Commons]
Imagine being able to erase bad memories or traumatic flashbacks – it could make a huge difference in treating a wide range of mental health issues.
Scientists might be onto something with a promising new approach: weakening negative memories by reactivating positive ones.
In a multi-day experiment, an international team of researchers worked with 37 participants to explore this idea. They first asked participants to associate random nonsense words with negative images, then tried to “reprogram” half of those connections to interfere with the bad memories.
“We found that this procedure weakened the recall of aversive memories and also increased involuntary intrusions of positive memories,” the researchers explain in their paper.
For the study, they used databases of images classified as either negative (like human injuries or dangerous animals) or positive (think calm landscapes or smiling children). On the first evening, participants went through memory training exercises to link the negative images with nonsense words created just for the study.
The next day, after participants had slept to solidify those associations, the researchers attempted to overwrite half of the negative connections by pairing the same words with positive images.
To reinforce this process, during the second night of sleep, the team played audio recordings of the nonsense words while participants were in the non-rapid eye movement (NREM) sleep phase, known to be crucial for memory storage. They monitored brain activity with electroencephalography (EEG).
Interestingly, when positive cues were played, brain activity in the theta band—associated with emotional memory processing—spiked.
By the next day, and even several days later, questionnaires revealed that participants struggled to recall the negative memories tied to the scrambled words. Instead, positive memories came to mind more often and were viewed more favourably.
“A noninvasive sleep intervention can thus modify aversive recollection and affective responses,” the researchers write. “Overall, our findings may offer new insights relevant for the treatment of pathological or trauma-related remembering.”
That said, this research is still in the early stages. The lab-controlled environment is great for precision but doesn’t exactly replicate how we form or experience memories in the real world. For instance, seeing unsettling images in a lab doesn’t compare to living through a traumatic event—those deeper, real-life experiences would likely be harder to overwrite.
We already know the brain replays memories during sleep to help save them, and many studies have explored how this process could be manipulated to enhance good memories or suppress bad ones. But with so many factors involved—like memory types, different brain areas, and sleep phases—it’ll take time to figure out how memory editing might work and how long-lasting the effects could be.
Still, this idea of overwriting negative memories with positive ones shows promise.
[source: Science Alert]
