Despite what many leading education commentators may tell you, there is no hard-and-fast scientific definition of what constitutes “long-term” memory, according to Nicole Long, assistant professor in the Department of Psychology at the University of Virginia. It might be information held in the mind for a few hours or it could be facts and figures that, once absorbed, are accessible for a lifetime.

“I do memory experiments where people have a delay between when they learn and when they’re tested,” says Long.

“That delay can be as little as eight seconds - should I be calling those experiments ‘working memory experiments’?” she asks. “There’s a group of people who don’t necessarily think that working memory is a thing separate from long-term memory.”

Such a belief seems to conflict with many of the simplistic models of the brain currently finding their way into classrooms, where the predominant view of a teacher’s role is to win the battle to get things out of the working memory and safely tucked into long-term memory. But Long argues there is no “good, clear delineation between short-term, working and long-term memory”, at least in a scientific sense.

It might be more helpful, she says, for educationalists to define long-term memory as the information that can be recalled by a pupil when it is needed - perhaps in an examination situation or when that individual has left school altogether.

So, what do we know about which information we tend to remember? And are there ways in which teachers might be able to tap into methods or techniques to help ensure the knowledge that they are seeking to impart doesn’t evaporate as soon as the bus home pulls up outside the school gates?

“There are at least two parts [to storing information],” Long explains. “You have to have learned it and you have to retrieve it. If you retrieve it, that means you both successfully encoded it and retrieved it.”

‘Failed retrievals’

It sounds straightforward but “failed retrievals”, where you did encode the information but cannot subsequently access it, are common.

“I could ask you to remember something vague, like what you had for breakfast, and you might say, ‘I don’t remember’. Then I could say, ‘did you have eggs?’ and you might say that yes, you did. The first part was recall, the second one was recognition.”

In this case, the memory is there in your brain somewhere, you just aren’t able to get at it. In an examination scenario, this could be particularly problematic, since while a pupil might “know” something, and be able to demonstrate that knowledge with a simple prompt, they may not be able to recall it under test conditions.

So, are there things that teachers can do to boost pupils’ long-term recall or is it more down to talent, with some people simply better at it than others?

“I don’t feel like there’s a totally clear picture yet, but there’s definitely a range of people in terms of ability,” Long says. “There exist people who have what’s called ‘superior autobiographical memory’, where they can remember every single day of their lives: the date, the day of the week, what they were wearing, what the weather was, what they had for breakfast on that day.

“Some of those things are personal, so you can’t verify it. But if you look at almanacs...they’re totally right. So, there’s clearly an ability there that some people have somehow tapped into.”

Work has been done to take images of these people’s brains in the hope it might shed light on what is behind this innate ability.

“One of the main regions for long-term memory is the hippocampus, and [researchers were asking] if maybe they had really big hippocampi,” Long explains. “But they don’t. So, it’s kind of hard to say what the underlying cause is.”

Memory deteriorates with age

Unsurprisingly, research does suggest that, as people age, their memory tends to deteriorate. One theory is that memory is linked to unique experience and, because adults have experienced more things, individual events are less likely to stick in the memory. “It’s likely that, over time, we lose the ability to create lots of unique new experiences because so much in our life is related to everything else in our life,” Long explains. “The flip side of that is...we will probably remember a lot of things from our childhood because more of those experiences are unique.

“[For example], I remember my fifth birthday party but I don’t really remember what I did on my 19th birthday. Maybe it’s because I’d had 13 other birthdays [in between], and it was not distinctive anymore.”

Does that mean the earlier periods of education are likely to be more memorable in the long term? We actually don’t know, says Long. “My own perception, having learned how to play piano at the age of nine, is that I can play from memory all of the major pieces that I learned...before I turned about 14 and I can’t remember the rest of them,” she says.

“Now, they got more difficult after that, so maybe that’s what it is - or maybe it was harder to learn the earlier ones, so I practised them more. But, anecdotally, it does seem like I had a critical period for memorising music.”

At this point, you are probably feeling a lot less sure about memory than you were before reading this article. However, Long does say the research can give us some useful steers - and a few may be familiar.

For example, a 2013 research paper by academics at a number of US institutions, including the University of Virginia, explored the sort of strategies that might lead to long-term learning. Among other things, it found that re-reading information repeatedly was not an effective way to learn.

“The number one strongest effect that has been seen over and over is...that reading is not useful,” Long says. “What you need to do is practise retrieving.”

In short, memory is not the number of times you put information into the brain, it is about practising how you get it out.

“The most effective things [for promoting memory] are testing yourself and testing students on material. I teach that to the undergraduates in my classes at Virginia, and I implement this by making them take quizzes every single week, so that they can practise engaging with the material.”

She cites the research of Henry L Roediger, at Washington University in St Louis, who studies so-called “testing effects”.

“If you have the option to re-read a list of words, versus practising retrieving those words, you’ll do better later if you practise retrieving them,” she says.

“At a basic level, when you’re practising retrieving, you are actually doing something more similar to what you’re going to do when you’re tested so, in the very simple sense, it makes sense,” she continues.

Novelty is important

She adds that another finding is that novelty is important - processing information in a variety of different ways.

“You have to do something more with the material,” she says. “If you aren’t processing it in kind of a different way, or a richer way, that’s not going to help you.”

Long concedes that teachers have a tough job on their hands encouraging 30 or so pupils per class to find interesting, novel ways to ensure they can commit lesson information to memory. And she adds that, in the search for constant novelty, you risk neutering any potential for novelty at all.

“It’s an open question, the extent to which [teaching] should be novel and exciting because once you start making everything novel and exciting, they all become novel and exciting,” she says. “It can become this repetitive loop.”

How do you know where the tipping point is? As with much of the research around memory, the answer is an empowering one for teachers: the gaps need to be filled with teacher experience.

While research can give us a better idea of how memory works, and is certainly worth engaging with, Long outlines a clear argument as to why it alone can’t provide the definitive route map for making learning stick. For that, you need a healthy sprinkling of teacher craft, too.

Chris Parr is a freelance journalist

This article originally appeared in the 11 October 2019 issue