Despite the decades of research on the brain‘s ability to voluntarily discard certain memories, scientists are still trying to pin down the mechanism behind it, which could eventually allow mental health professionals to offer their patients the option of getting rid of memories which trigger involuntary, maladaptive responses.
Now, a new study published in the Journal of Neurosciene by a group of researchers from the University of Texas, Austin suggests that attempts at deliberately forgetting something may require a greater amount of mental effort than trying to remember it.
Rather than focusing on what‘s going on in the brain‘s control structures (e.g., the prefrontal cortex) and long-term memory structures (like the hippocampus) when people try to consciously forget something, the current study looked at activity in perceptual areas.
“We’re looking not at the source of attention in the brain, but the sight of it,” said senior author on the study Jarrod Lewis-Peacock, an Assistant Professor of Psychology at UT Austin.
Specifically, the researchers showed a group of healthy adult subjects images of scenes and faces, and then asked them to either remember or forget them, demonstrating that human do, indeed, have the ability to forget things at their own choosing by expending a certain amount of effort.
“A moderate level of brain activity is critical to this forgetting mechanism. Too strong, and it will strengthen the memory; too weak, and you won’t modify it,” said Tracy Wang, lead author on the study and a postdoctoral fellow at UT Austin.
According to Wang, if the level of intention to forget, which follows the prior activation of a specific memory, reaches a certain 'sweet spot', the memory in question becomes more likely to gradually fade away.
Lewis-Peacock is currently working on a neurofeedback-based study to investigate how much attention is allocated to different types of memories, given the finding that forgetting a location is easier to do than forgetting someone's face, potentially because the latter carries more emotional information.
“This will make way for future studies on how we process, and hopefully get rid of, those really strong, sticky emotional memories, which can have powerful impact on our health and well-being,” concluded Lewis-Peacock.