Have you ever struggled with a missing memory you’d like to recall but can’t seem to–the title of a book or name of an actor, for example?
Memory lapses can be scary and frustrating. However, long-term memories (the ongoing storage of conscious and unconscious information for a few days or for many years), naturally fade as we get older. This is completely normal. In fact, if you could count memories (which you can’t, by the way), you’d discover that more than half of what we experience is inaccessible to memory within a single hour. That’s because memories often start decaying as soon as they have begun to form.
Important information gradually moves from short-term memory (which has a fairly limited capacity; it can hold only about seven items for no more than 20 or 30 seconds at a time) into the relatively larger capacity long-term memory. Unfortunately, we also lose the information in long-term memory over time as we age.
However, just because memory loss is a natural occurrence that becomes more pronounced as we grow older doesn’t mean we can’t do anything to slow it down and expand our long-term memory. In fact, improving our long-term memory is simpler than you might think.
How you can create durable memories
According to a recent study from the University of Sussex in the U.K., rehearsing information immediately after being given it may be all you need to make it a permanent memory.
The study found that the brain region known as the posterior cingulate–an area whose damage is often seen in Alzheimer’s patients–plays a pivotal role in creating permanent memories. This region not only helps us to recall the details of an event, but also helps integrate the memory into our knowledge and understanding, thereby making details of the event more resistant to forgetting.
The study involved a group of participants who were shown 26 short videos clips from YouTube. The clips were around 40 seconds long with a narrative element. For the first 20 videos, the participants were given 40 seconds after each video to relate (either in their heads or out loud) details of the video. For the remaining six videos, this rehearsal period was not given.
The researchers found that the participants were still able to recall many details of the videos they had rehearsed up to two weeks later. However, the participants had largely forgotten the non-rehearsed videos two weeks later. MRI scans revealed that the same area of the brain–the posterior cingulate–was most associated or linked with the benefits of rehearsal.
The researchers could even predict how well the videos were remembered a whole week later based on the degree to which brain activity matched when watching and rehearsing the videos.
“We know that recent memories are susceptible to being lost until a period of consolidation has elapsed. In this study we have shown that a brief period of rehearsal has a huge effect on our ability to remember complex, lifelike events over periods of 1-2 weeks,” said Dr Chris Bird, the lead researcher of the University of Sussex study.
What this scientific revelation means
“The findings have implications for any situation where accurate recall of an event is critical, such as witnessing an accident or crime. Memory for the event will be significantly improved if the witness rehearses the sequence of events as soon as possible afterwards,” said Dr. Bird, whose research group is conducting further studies to investigate how these processes relate to memory loss in Alzheimer’s disease.
This particular study, published on October 27th in the Journal of Neuroscience, appears to reinforce what German cognitive psychologist Hermann Ebbinghaus discovered in the 19th century. Ebbinghaus discovered that memories grow continuously weaker, but that the rate of “decay” lessens each time you review the information.
Ebbinghaus’s “forgetting curve” explains why we so often remember nothing shortly after cramming intensely for an exam. It’s because all the learning takes place in a week or so and, if not subsequently reviewed, it begins to be forgotten after only a month. However, if reviewed, memory gets stronger and stronger. This discovery has become one of the few certainties of neuroscience.
So, review or rehearse memories after a few seconds, then after a few minutes, then an hour, a few hours, a day, a week, a month, a year, two years, five years and so on. This is known as spaced repetition, and is very effective for improving long-term memory and enhancing learning. It can keep your most precious memories intact and available for as long as possible.