Remembering stuff for a little while
You know that little routine you do when you need to remember a phone number long enough to call it? If you’re like me, you’ll repeat the number over and over until you dial it. Then, as the conversation starts, you’re likely to forget it.
Others of you may write it down. Some may sing it to themselves because the numbers lend themselves to a particular tune or rhythm.
What we’re all doing is exercising a particular memory store called working memory. Back in the day, we called this short-term memory because, well, that’s kind of what it is.
In contrast, naturally, is long-term memory because that term, too, pretty well describes what it is.
But working memory is more than that
Yes, it doesn’t last long. But we hold it in memory for seconds to minutes, while we do something with it, or so that we can achieve something. We might even stash something in working memory, do something else, and then go back to it.
Because of this active nature, keeping things alive and accessible, while we can manipulate them and process them, we now call it working memory.
You’re using it as you read this.
It’s incredibly flexible, but it only holds so much and, as you put more in, other stuff comes out. As you read the next few words on this page, earlier ones drop out. But you hold enough in your memory to make sense of where you are in the sentence, while at the same time keeping track of the entire post and its general argument. Cool huh.
(In contrast to working memory, long-term memory seems limitless. Yes, memories can decay but, there seems to be no end of storage. If we need more, we grow it.)
It’s a kind of magic
There’s a famous old study called The Magical Number Seven, plus or minus two: Some limits on our capacity for processing information, published in 1956, by George Miller. It’s a great, famous and, still cited, piece.
Essentially he suggested that working memory’s limit is seven things, plus or minus two – so between five and nine. Like phone numbers. Which is an explanation for why phone numbers are the length they are. But where Miller went then was to suggest that the things, the chunks, can be massive.
Chunks of memory
If I give you the letters a a a b c h i l l m n n o r to memorize, you’re forced to use a list of 14 things.
But then, probably, some cool things happened in your brain. Immediately you would have seen three of the letter ‘a’, that the last ‘a’ is also part of ‘abc’ and the ‘c’ forms part of the word ‘chill’ in the middle. Or it’s just hill, the second ‘l’ of which is also part of ‘lmn’, with the word ‘nor’ at the end.
All of a sudden it’s not 14 chunks (letters in this case) but many fewer:
You’ve just been chunking. 14 letters is too many for your working memory to manage, so you grouped letters together in a meaningful way, reducing the number of chunks to five, and making it waaaaaay easier to work with, and to remember.
You’re probably fine now as you’re down to seven, plus or minus two. But if I rearranged them for you into the even more meaningful ‘Abraham Lincoln’, well, now there are only two, highly meaningful, chunks, even easier to remember still, but exactly the same number of things to memorize, or deal with.
Side note: Reducing chunks and adding meaning makes the whole thing easier. It’s incredibly helpful to connect things to remember them.
As a practical application, if you have a decision to make, reduce the number of factors you have by chunking, and prioritizing. Naturally, you need to have seven, plus or minus. Additionally, depending on the type of chunk, or the more complex the chunks, the fewer chunks you should aim for.
For best results, try to get down to four or fewer.
But what working memory does not do, for all its awesomeness, is give us a thorough mental workout.
In fact, it’s quite the opposite, and therein lies the catch.
The working memory workout
You use working memory all the time, and couldn’t get through a day without it. In general, it’s better in younger people than old, and speed decreases with age also.
It’s located particularly in our frontal lobes, in a part of the prefrontal cortex, but with significant connections elsewhere.
And what’s of interest to me, and, hopefully you, is the way we are increasingly called upon to use working memory, at the expense of long-term memory, and deep thought.
The amount of information we are required to process each day is of such magnitude, and at such pace, that it speeds through working memory to be quickly replaced by something else.
In addition, we are surrounded by distractions that demand a response from us. The soft ding of an email, the ping of an instant message, the chime of an update, all interrupt focused attention and the long-term memory process.
Our brains carry an inbuilt orient response that directs our attention to new or novel stimuli, dragging our attention away from what we were doing and onto the new thing.
For online examples, banner ads entice us with flashing or moving parts, promoting an orient response. Pop ups do the same. Hyperlinks encourage us to hop to another information thread. They come thick and fast, not allowing the brain to settle on a task, and inducing a click and go mental style.
All of these things encourage active working memory use and, to be fair, it looks like we’re getting better at working memory. But, and here’s the rub, it’s at a cost.
The downside of working memory use
In order to build brain tissue, develop mental strength, and build a buffer against the declines of age and the deterioration or ravage of disease, we must spend time with information, forcing the brain to work, firing circuits repeatedly.
Repeated use of the brain circuits involved in learning increasingly challenging things, with sustained, focused attention, causes the brain to grow. It grows new connections and new cells and reinforces old ones.
A brain that exercises only working memory, because it does not get the chance to do anything else, does not do the necessary work to stay fit. It is, in brain terms, flabby. It might be able to toggle extremely well between tasks, watch a young person skip between their devices, but it doesn’t develop any mental depth or brain reserve.
As an example, note the last time you spent surfing the internet. You could happily spend a couple of hours hopping from one interesting (orienting) thing to the next and, at the end, remember next to nothing of it.
Yet your working memory is active the whole time, allowing you to skip happily from one thing to the next.
You’ll be tired b the end of it (continual orienting takes energy from the brain) but have achieved no learning. And no long-lasting positive brain effect.
Mental flab will not protect us from deterioration. Worse, because we know that the use it or lose it principle applies to brain tissue, we forget how to engage in effortful, sustained thought, preferring the easy come, easy go ability that working memory facilitates.
Much less ability to negate the effects of dementia, old age decline and the changing brain of middle to late adulthood. Fewer mental resources to call on in middle to late adulthood.
So here’s the take home bit
We need to have periods where we have the time to concentrate on something for a sustained period, without interruption or distraction. Effortful, prolonged concentration, particularly on new skills, increases brain tissue, and it’s this extra mental muscle that can help us fend of the worst of aging.
Make sure you do the hard mental yards. Your brain will thank you for it. So might your family.
Impressive words to drop into the morning coffee chat
Prefrontal cortex, working memory
What do you think?
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