8.7 George Miller’s Psychological Study to Improve Short-Term Memory

Jan 14, 2020 | Cognitive Psychology, Courses, ch8 How the Brain Stores & Recalls Information

Wouldn’t it be nice to improve your short-term memory? According to one psychological study, there are, in fact, ways you can organize sets of new information to make them easier to remember. Based on the study, this lesson examines a method that can increase your short-term memory.

Magical Number 7

Is it possible to improve your working memory? Studies have shown that most people have similarly-sized working memories, but we may employ certain cognitive strategies to squeeze more information into a limited number of slots.

Let’s look at a series of numbers for a few seconds:

2 6 9 31 20 6 3 3 25 1 17 9 5

Now see how many numbers you can remember, in the proper order.

Here’s the list again so you can check your memory:

2 6 9 31 20 6 3 3 25 1 17 9 5

How many of the numbers did you remember? If you recalled somewhere between 5 and 9 digits, then you’ve reinforced a study conducted by psychologist George Miller.

Miller published the study under the title, ‘The Magical Number 7, Plus or Minus Two.’ It has long been understood to mean that there are limits on how many new items we can introduce at any one time to our short-term memory, and that the limiting number is ‘seven, plus or minus two.’

At first glance this seems fairly straightforward. But think: what constitutes an ‘element’? Look at this string of numbers:

2 6 9 3 2 6 3 3 2 1 1 9

Chunking Numbers

If you string together the numbers into groups of three, 2-6-9 then becomes one element (269), instead of three separate pieces of information. One 3-digit element is easier to remember than three separate numbers. The principle of chunking, or organizing a bigger string of new information into smaller chunks, can potentially increase the number of individual items that our short-term memories can recall at any given time. Grouping the single-digit numbers into groups of three is chunking.

269 326 332 119

Now let’s try to remember this string of numbers:

9 8 7 1 2 3 9 0 2 1 0

Now see how many you can remember:

987 123 90210

Were you able to remember more of this string than the first one? If so, it might be because, even though it contained the same amount of numbers, you may have found more memorable chunks within the larger sequence.

Chunking Letters

Similar techniques can be used with letters. Try remembering this set of letters:


Now, try to remember this set of letters:


Did that second list look more familiar? These letters are airport codes for JFK Airport in New York, O’Hare Airport in Chicago and Los Angeles International Airport in LA. Suddenly, instead of having to remember nine random letters, all you have to remember is three airports.

Even still, though, the list may have been too long. Some researchers say the number of new elements we can remember is actually only around three or four.

Factors, such as how difficult or foreign the new material is to us, and how well it’s presented, affect our ability to remember. But in general, if you can find a way to chunk information into less than seven groups, you’ll have a much easier time storing it in working memory.

8.9 Retroactive Interference: Definition & Examples
8.6 Improving Retrieval of Memories: Mnemonic Devices