In recent years, a significant amount of research has been done on memory, including research on how we forget and why. A memory is stored as an engram, a physical trace of memory in the brain. Forgetting means losing or losing track of that trace. A great deal of the research on engrams has been done on mice because their memories, whether retrieved, forgotten, or erased, tend to be simple and easy to interpret.

A recent article in The Scientist looked at some new mouse research on forgetting, which provides some reassuring results. University of Alberta neurobiologist Jacob Berry explained that a 2023 open-access study is actually still there, even when it can’t be retrieved due to some interference:

“It’s almost like it gets demoted by the interference to a dormant stage. And then they show pretty elegantly that in that stage, they’re able to either update, or they can actually rescue or revive, the memory.” …

Shelby Bradford, PhD, “Forget Something? You’re Supposed To Do That,” The Scientist, January 22, 2024

The researchers put it like this:

Long-term memories are stored as configurations of neuronal ensembles, termed engrams. Although investigation of engram cell properties and functionality in memory recall has been extensive, less is known about how engram cells are affected by forgetting. … Taken together, these findings indicate that retroactive interference modules engram expression in a manner that is both reversible and updatable. Inference may constitute a form of adaptive forgetting where, in everyday life, new perceptual and environmental inputs modulate the natural forgetting process.

Autore L, O’Leary JD, Ortega-de San Luis C, Ryan TJ. Adaptive expression of engrams by retroactive interference. Cell Rep. 2023 Aug 29;42(8):112999. doi: 10.1016/j.celrep.2023.112999. Epub 2023 Aug 16. PMID: 37590145. The paper is open access.

Berry, who was not involved in the study, added a comment,

“We always suspected that maybe [memories] can be put into a dormant state and be revised, or changed, or brought back up,” Berry said. “To really see that at the engram cell level really helps confirm that, and I think it will open up the field to looking into what dormant memories are. What makes them different than a regular memory that’s easily expressed? And I think those kinds of things can have impacts in understanding lots of disorders where there’s a lot of forgetting.”

Bradford, “Forget Something?”

When is forgetfulness a real problem?

The people who pay the most attention to studies about remembering and forgetting are typically seniors, who fear that forgetfulness could signal the onset of dementia. But from the Mayo Clinic, we learn:

Normal age-related memory loss doesn’t cause a significant disruption in your daily life. For example, you might occasionally forget a person’s name, but recall it later in the day. You might misplace your glasses sometimes. Or maybe you need to make lists more often than in the past to remember appointments or tasks.

Staff, “Memory loss: When to seek help,” Mayo Clinic

In fact, a case can be made that forgetting some things is only to be expected. Seniors, relative to teenagers, have vast memories to manage. How many Lindas or Johns have many seniors met? For that matter, glasses are very easy to misplace when we are busy, if we only need them for other tasks anyway. And maybe, decades ago, children’s birthdays didn’t require lists. But grandchildren’s birthdays probably do if the kids aren’t on hand to remind everyone…

But the Clinic also advises that it is time to look for professional guidance when things like this happen:

● Asking the same questions repeatedly

● Misplacing items in inappropriate places, such as putting a wallet in a kitchen drawer

● Getting lost while walking or driving in a familiar area

Staff, When to seek help”

Frequent episodes of that kind of forgetting imply that the person is not in touch with larges area of memory, as opposed to losing track of an engram or two. Fortunately, many causes of memory loss (medication problems, emotional disorders, too much alcohol, sleeplessness) can be addressed successfully so dementia should not be assumed.

Tips for improving memory

Meanwhile, researchers have discovered a few other things we should note if we want to get the best from our memories:

● From Robert N. Kraft at Psychology Today “Memory for our actions is far better than memory for our thoughts. If we have an insight we want to remember, we should write it down, otherwise it may never be recovered.” (March 24, 2022) Yes. The sophomore who is struggling to remember the Original Idea that would surely ace the essay contest can — frustratingly easily! — remember exactly what pizza she ordered last Saturday night.

● From Kendra Cherry at VeryWell Mind: Those who must learn a new area of expertise should keep in mind that “Researchers have found that information is organized in memory in related clusters.” Structuring and organizing the materials to be learned and making outlines and notes help our memories group the related concepts together for quicker, easier access.

● From Coursera staff, we learn, that spacing out learning sessions (spaced repetition) is more useful than trying to learn something new all at once (cramming). That gives our minds time to understand the material, making it easier to store for easy retrieval.

And we should all remember, as the proverb puts it, “Experience is the father of wisdom and memory the mother.”

You may also wish to read: Memory leans more on the brain’s electric field than on neurons. MIT researchers compare the electric field to an orchestra conducting the neurons as players. 23 January 2024The neurons associated with our memories may change; it’s the electric field that holds the memories together, the neuroscientists say.