Why our overloaded brains keep forgetting things

In our busy, technology-driven world, with its constant flurry of emails, news alerts and other distractions, it is tempting to think our brains have hit information overload.

As we battle to process and retain data fired at us from all directions, how do we stop our brains from reaching full capacity?

Experts say the prevalence of smartphones in our daily lives can both help and hinder efforts to marshal memories.

Digital distraction reduces engagement

One the one hand, if you are scrolling through social media while listening to someone talking, it is unlikely you will remember much of the conversation.

“We can use them while we do other things, but that reduces our amount of processing we can spend on those other things,” said Prof Alex Easton, of Durham University in the UK, who co-edited the Handbook of Episodic Memory.

“If you want to remember something well, you have to be really engaged with it. You have to attend with it. That helps you process it and keep it in your memory.

"The more distracted you are, the less that material will be processed by your brain, the less your brain will remember that material.”

When people are doing too many things at once, their cognitive load, to use the term favoured by psychologists, is high, and memory suffers.

Not living in the moment

Technology can also distract us when we are at, say, a music concert. Prof Catherine Loveday, of the University of Westminster, who wrote The Secret World of the Brain, said people have poorer recall of a concert if they have been busy taking videos and photos during it.

“We’re often not in the moment,” says Prof Loveday. “Our brains are not recording everything going on around us because we’re not fully there.

"People can get to the point where they rely on the smartphone to record things and therefore are not fully immersed in what they’re experiencing.”

In other circumstances, technology can keep track of things, such as flight details, appointments or shopping lists, that we have little desire or need to commit to memory permanently.

Technology as a memory aid

“It can relieve our biological memory from a load of details that we don’t need to clutter it with,” said Prof Robert Logie, of the University of Edinburgh in the UK, who is co-editor of books including Working Memory: State of the Science.

So in today’s world, we don’t need to remember everything — we just need to remember where to find that information.

This process of “cognitive offloading” may raise concerns that technology is carrying out work that our brains should be doing.

But Prof Logie said such worries are nothing new, dating back at least to the Ancient Greeks, who worried that books would stop people using their memory.

Life a blur during pandemic

There has been speculation that the Covid-19 pandemic and even the war in Ukraine have acted as a drag on our ability to remember.

Prof Loveday researched the effects of the pandemic and found that while people felt their memories had been affected, “for people in our study, this did not seem to be the case”.

She notes, though, that people with dementia may have experienced a worsening of memory problems because of the pandemic, and some people with long-Covid have had memory issues.

The pandemic may have affected many of us because almost every day during lockdown was the same, so there were fewer contextual cues to help recall events.

“Time ticked on the way it always did … but the context wasn’t changing,” said Prof Easton. “We’re seeing that many of us found memory quite difficult. This thing about context and how we distinguish events by using contextual cues is really important.”

Also, people socialised less, and under normal circumstances, socialising — chatting about what we have done — helps to consolidate memories. Staying at home more may also have been an issue.

“Being out and about triggers our hippocampus, where are memories are stored,” says Prof Loveday. “People not moving around their environment may have impacted on that.”

The pandemic has additionally been a source of stress, and high levels of stress are physiologically not good for memory, Prof Loveday adds. Stress affects all three stages of remembering: encoding, storing and retrieving a memory.

“Those are big, stressful events that take lots of your processing power,” said Prof Easton. “It probably makes you more distractible and less able to process material when you’re stressed, but also when you’re stressed it may make it harder to retrieve that material that you already have there.”

Sleep loss affects memory

Aside from stress, lack of sleep can affect memory, because good-quality sleep helps us to learn or encode memories and, when it comes after learning or encoding, can retain or consolidate memories, said Prof Edwin Robertson, professor of brain and cognitive sciences at the University of Glasgow in the UK.

“Consequently, sleep loss can have a double whammy effect upon memory, impairing its acquisition/encoding, and its retention/consolidation,” he said.

“The duration of sleep and its quality are thought to be reduced in modern society, and certainly are impaired as we age. Sleep may also have been impaired by the pandemic, and now the subsequent stress of cost of living.”

Stress can be one factor why we sometimes cannot recall information that we actually know. Another is experiencing something out of context.

An example is the “butcher on the bus” phenomenon, in which someone spots a fellow bus passenger they know, but cannot recall who they are.

The person is the local butcher, but if he or she is not in the butcher’s and is wearing something different, he or she is harder to identify.

“One day, you might just not have all the pieces to bring that information to mind,” said Prof Easton. “Another day, you might have a different set of cues that are giving you a reason to ask for that information. Therefore, you bring it to mind more easily.”

Prof Robertson highlights the way that memories that are similar can compete with one another. For example, a person may keep recalling a word that sounds the same (is phonologically similar) as the word they are trying to remember, but has a different meaning.

“You might want to ask for the fruit papaya, but instead only come up with the Spanish dish paella,” he said.

How to improve memory

A crucial step to improving memory is, said Prof Robertson, removing detrimental influences. So getting enough sleep, not flip-flopping between tasks and eliminating distractions can all help. Getting more exercise can help to improve memory.

Here are strategies to improve memory in specific circumstances.

Self-testing

Prof Logie recommends self-testing to improve memory of, for example, material that needs to be learnt for an exam.

Rather than reading through something multiple times, it is better to read through it, put aside the source of the material, such as a book, try to remember it and test whether you have done this successfully.

“This repeated retrieval has been shown to be a very effective way to improve your learning,” he said. “By improving your learning, you improve your memory of what you have learnt.”

Thinking about or talking about an event immediately after it happens retrieves and strengthens the memory.

“Forgetting details about events is very rapid,” Prof Logie said. “That’s helpful because we’re forgetting a lot of trivial details.”

To prevent us from forgetting things we want to remember, Prof Logie suggests going over a lecture, for example, straight after it finishes.

“If you wait longer and try to remember it, it becomes more difficult to retrieve it because of the forgetting process,” he said.

Remembering names

Sometimes we struggle to recall the name of a person we have chatted to at a work or social event. One factor behind this may be that, at least in western European cultures, people tend not to say the name of the person when they are talking to them.

“So it’s hardly surprising people forget names, because they’re not using them,” Prof Logie said. “If it’s a face-to-face conversation, you have 10 minutes worth of memory of the face, but only a few seconds of the name.”

A simple answer is to say the person’s name every so often during the conversation, as this “reinforces the memory”.

Prof Easton suggests making an effort to pay attention and rehearse a person’s name in your head after hearing it for the first time.

“But mainly just not be distracted, but take that information in. In some ways it’s all about being present in the moment,” he said.