In this video, we're going to talk about a few strategies that can be used to increase short-term memory and working memory capacity. The first of these is very simple; it's just rehearsal, which is the mental repetition of information to basically keep it active in short-term memory. So if you've ever met somebody at a party and you just think to yourself, okay Amy, Amy, her name is Amy, don't forget her name is Amy, you are rehearsing that information. Rehearsal is actually partially responsible for a really cool effect that we see in psychology known as the serial position effect, and this is the tendency for people to recall the first and last items on a list more so than the items in the middle. For example, if I was to read a list of planets to you, I'm sure that you know your planets but just as an example, you would have an easier time remembering the first few planets, Mercury, Venus, Earth, and that is known as a primacy effect.

Prime, just referring to, like, the first of something. This primacy effect happens because of rehearsal. Because you heard those first, you just have more time to mentally rehearse them. So the entire time that I'm going to be reading that list, you can just keep saying Mercury, Venus, Earth over and over in your head. That rehearsal is actually why you end up forgetting the items in the middle.

Because you're so busy trying to keep those first few items active in your short-term memory, as these new items in the middle begin entering it there is just no space for them and so they basically get forgotten very, very quickly. Now, when you remember the last item on a list we call that the recency effect, and we see it just because quite literally that item most recently popped into your short-term memory. Basically, it just hasn't had time to be forgotten yet. So if I finish reading this list and then said, okay, say it all back to me this one is just still in short-term memory because it just got there, and these are there because you have been rehearsing them the whole time, and these probably got lost somewhere along the way. So that is why we see that serial position effect.

Now one other strategy that we can use to increase our capacity is known as chunking. Chunking is basically grouping pieces of information together into a single meaningful unit. For example, I would bet that you read this as 2020 and it's just a year in your head. Right? If I asked you to read this you probably wouldn't say 20, 20, right? You don't read that as four discrete pieces of information, you read that as one single chunk.

That is a chunk. Now when I was talking about our short-term memory capacity being 4 plus or minus 1 you might have been thinking, like, that sounds really low, and it does, but that's because that capacity actually refers to chunks. Our short-term memory capacity is 4 plus or minus 1 chunks, not discrete pieces of information, and chunks can actually be a little bit bigger than you might be thinking. Now these strategies can be applied both consciously or unconsciously. You probably never had to, like, sit yourself down and say, okay, like, 2020 is going to be a chunk from now on.

Like, you never had to do that. Your brain just automatically did that for you. Right? But you can purposefully employ these strategies, things like rehearsing a person's name. If you have to remember a verification code, you might purposefully kind of chunk it into smaller units to help you remember it.

We can do these consciously or unconsciously. Now, there are a few additional factors to consider when we are thinking about short-term and working memory capacity because this can be very variable. One thing to note is that expertise in a subject will often increase capacity as well as attention or interest. That is usually going to increase capacity as well. So if you are really focused, really paying attention, you probably going to have a bit of a higher capacity on average.

And then things like physical discomfort, such as being hungry, tired, or stressed, on average that is going to decrease capacity, and that is true really for most cognitive processes. Alright, so those are some ways that we can increase our short-term and working memory capacity and I will see you guys in our next video. Bye bye!