This study is good news if you think your memory is bad

It’s a sobering thought, but everyone inevitably forgets some memories as they age and grow older. The human memory is an incredible, intricate neural system.

But, at the same time, it’s far from perfect. We all forget things, and sometimes people end up remembering events or moments that never happened in the first place.

While these bumps in our collective memory lane are unavoidable, a new study finds that the memories we do remember are actually quite accurate the vast majority of the time.

Just released by the Association for Psychological Science, researchers report a group of participants accurately remembered past events (dating back as far as three years in some cases) with 94% accuracy.

People tend to be wary of their memories, often writing off certain recollections as unreliable or possibly made up. These findings throw that narrative on its head. Even among older adults, what we remember about the past is usually quite accurate. 

“These results are surprising to many, given the general pessimism about memory accuracy among scientists and the prevalent idea that memory for one-time events is not to be trusted,” says lead researcher Nicholas Diamond, a former graduate student at Baycrest’s Rotman Research Institute (RRI), and current postdoctoral researcher at the University of Pennsylvania.

“This study shows us that memory accuracy is actually quite good under normal circumstances, and it remains stable as we age,” study co-author Brian Levine, a senior scientist at RRI and a professor of psychology and neurology at the University of Toronto, adds in a release. “These results will be helpful for understanding memory in healthy aging.”

Even the researchers themselves were surprised by how well the participants performed. Before the experimental portion of this study, a group of 400 academics and memory scientists were asked to estimate the reliability of human memory. They concluded it’s about 40% accurate at best, which is a far cry from the 94% accuracy shown by study subjects.

This certainly isn’t the first study to test the efficiency of human memory, but the research team made sure to set their work apart from the pack. First, participants were placed within “an immersive, scientifically controlled event” specifically created for this research. Put in less scientific terms, each person was given an audio-guided art tour lasting 30 minutes. Two days later everyone was asked to remember as much as they could about the art tour.

Next, to test more long-term memory accuracy, another group of participants was asked to remember details of a “standardized, scripted procedure” that they had received anywhere from one month to three years prior. This setup was an important part of the study’s overall findings, as it allowed study authors to both assess the role of time delay in memory recall and easily verify memory accuracy thanks to the standardized nature of the procedure.

Across both experimental conditions participants’ reported memories turned out to be quite accurate. That being said, the longer it had been since a specific event, the fewer details participants remembered. 

To be clear, these results don’t mean subjects remembered everything about the events they were recalling. At best, researchers report participants remembered about 25% of their experience.

“This suggests that we forget the majority of details from everyday events, but the details we do recall correspond to the reality of the past,” Diamond notes.

The fact that researchers were able to confirm the accuracy of the memories participants remembered makes this study far more reliable than other memory projects. Earlier studies had asked participants to subjectively recall personal events from their past, but there was no way to verify the accuracy of those memories. Alternatively, other projects have had participants memorize and recall random lists of words or numbers, but there’s a big difference between something like that and recalling legitimate memories from one’s life and experiences.

“This pessimism originates from earlier studies showing that memory can be manipulated using certain testing methods,” Levine explains. “While those studies were important in showing the ways in which memory can fail, we wanted to know what happens when people freely recall events without such manipulation. We found that they are overwhelmingly accurate.”

Humanity is blessed with several distinct traits and abilities that serve to enrich our lives, but perhaps none are as important as our capacity to remember. The past dictates the future, and one’s memories shape their very identity. So, it’s nice to know we can trust our memories. 

The full study can be found here, published in Psychological Science.