Number facts Graphic

7 memory myths exploded

by Matthew Leitch, 14 October 2004

Why 7 memory myths? Of course, the magical number 7, plus or minus 2! It is 7 myths because 7 is a good number for memory right? Wrong, and it gets us started with our first memory myth.

Myth 1: The magic of 7 items (plus or minus 2)

This myth comes from a very good, but wrong, theory by George Miller in his 1956 paper ‘The magical number seven, plus or minus two’. It is based on the idea that we have a short term memory store which holds things for a few seconds or tens of seconds, and from which we may or may not move information on to the long term store. The capacity of the short term memory seemed to be around 7 ‘chunks’, give or take 2.

There are really two myths here. The first is that we have a short term memory store. Later work showed that we don't. It seems to be a mixture of very short term sensory stores (really short term) and memories that are neither short nor long term. Whatever the true explanation is the notion of two boxes, one labeled STM and the other labeled LTM, is history.

The second myth is that presenting or arranging items to be remembered permanently in groups of seven will somehow make them easier to memorize. Clearly this is taking the original research and trying to apply it to a very different situation. If you still think it might make sense try remembering a list of 7 things as compared with a similar list split into meaningful groups. For example, 7 animals in one list versus 3 types of big cat, 2 types of bear, and 2 types of reptile. The structured list with sub-lists of 2 or 3 items is much easier to learn.

Myth 2: The primacy and recency effects mean we should take a 5 – 10 minute break every 30 minutes

The pattern of rest and work may be reasonable, but the justification is not. Recency and primacy effects are seen when you try to memorize a list of words, in sequence. The words early in the list are more likely to be recalled in a subsequent test. The words at the end of the list are also more likely to be recalled, but only if the test is almost immediately after learning and nothing distracts you from hanging on to those last few items! If you are distracted for even a short while the recency effect disappears.

For other memory tasks the primacy and recency effects either don't occur or the experiment hasn't been done yet. The problem is that very little of our learning involves learning sequences of words. With more typical materials there are other effects, such as a kind of ‘warm up’ effect, that change the situation considerably.

There is even some evidence to suggest that a 10 minute rest is too long, and that 30 seconds to 2 minutes of rest in between much shorter periods of work would be better. However, the evidence is far from clear.

Myth 3: Memory uses images

In our minds we can see, hear, or feel images of things we are recalling, so it's natural to think that we remember things as images. But we don't. The images are reconstructed from facts we memorized, rather like a computer generates two dimensional images from a three dimensional model expressing facts mathematically. (If you've seen Toy Story, Shrek, or any of those computer animated films you were seeing images generated from a factual model.)

There have been some clever experiments to demonstrate this but to save time consider this question. If you recall something you have seen, can you imagine it from an angle you did not actually see it from originally? If your mind had created a memory that was a literal recording of the original images you witnessed then your memory would be like a videotape and you would not be able to imagine something you had not seen. But you can.

Or try this simple experiment. Look at something and notice as many facts about it and its appearance as you can. Later, try to imagine it. Do you notice that the images are sharper and more detailed? Just looking at something, even if you stare hard, does not have the same effect.

Myth 4: The best memory is visual memory

This powerful myth probably comes from two sources. Firstly, a lot of advice on memory improvement is based on using images that combine two ideas into one. Secondly, experiments by Ralph Haber and colleagues in the late 1960s seemed to show that human visual memory was amazingly capable.

When I first tried memorizing a list of unrelated words by linking them using visual images it worked brilliantly straight away. I, like most people, was blown away by this incredible experience and for a while tried to find ways to make use of it in my studies.

The experience is so powerful it is easy to think that the visual aspect of the linking is important, but it seems it is not. If you make up a sentence that links the two words into one idea that is just as effective. Imagery is not the active ingredient

Haber's experiment involved showing people 2,560 pictures from a varied slide collection and later testing whether subjects could remember the pictures. The key to understanding the high memory scores that were achieved is that the method of testing memory was the most flattering possible. The subjects were shown pairs of images, one of which was one they had been shown before. They had to indicate which picture they thought they had seen before. Imagine if subjects had instead been asked to draw every picture!

Another factor in this experiment was probably the variety of pictures used. The images were not too similar to each other. If his slide collection had consisted of hundreds of very similar flash-lit photos of his friends at parties I suspect the scores would have been much lower.

Myth 5: Linking with bizarre images is best for memory

This follows on from Myth 3 and Myth 4. Nearly every website on the Internet that gives advice on memory gives prominence to mnemonics based on linking things with visual images. The majority say that bizarre images are better than mundane ones.

Linking information using made up connections rather than real reasons should be a last resort, not your main memory technique. It risks confusing your understanding with a lot of alien and irrelevant associations. Use it only with totally meaningless, patternless material, and that is very hard to find.

Bear in mind that the initial effectiveness of association using bizarre images is not a reliable guide to later effectiveness. Once you've been using wacky images for a while the bizarre starts to become commonplace. It all becomes a jumble and now you have no way to use logic to distinguish right from wrong.

Myth 6: Intention to remember increases your memory ability

It is true that if you set out to remember something you will usually hang on to more than if you did not intend to remember. However, this is not because of the intention to remember per se. What intention does is make it more likely that you will think the thoughts that create memories.

If you think those thoughts without having an intention to remember you will remember all the same. Also, if you intend to remember but don't think effective thoughts you will find the results disappointing.

To improve your memory, therefore, focus on skillful thinking, not on trying hard.

Myth 7: You must believe you can remember

Again, it is true that people who think they can remember tend to perform better than people who think they cannot. However, this is not due to the belief per se. People who believe they can memorize something spend more time on task and less time drifting off onto other things. If at first they don't succeed they keep trying whereas the non-believer is inclined to give up too quickly.

However, if you have low confidence but still stick to the task you will do better than someone who is confident (perhaps over-confident) and does not put in the time and focus needed. Ultimately, self confidence needs a rational foundation, and that comes from building sound memory skills for the materials you need to master.


Thanks for letting me get that off my chest. This list is just a smattering of psychological mis-information that has escaped from academia into the popular imagination and lived on even after the original theory has been discredited.

About the author: Matthew Leitch has been studying the applied psychology of learning and memory since about 1979 and holds a BSc in psychology from University College London.

© 2004 Matthew Leitch