Scientific American: How were you able to recite from memory the first 22,514 numbers of pi? And do you have advice for people looking to improve their own memory?
Daniel Tammet: As I have already mentioned, numbers to me have their own shapes, colors and textures. Various studies have long demonstrated that being able to visualize information makes it easier to remember. In addition, my number shapes are semantically meaningful, which is to say that I am able to visualize their relation to other numbers. A simple example would be the number 37, which is lumpy like oatmeal, and 111, which is similarly lumpy but also round like the number three (being 37 × 3). Where you might see an endless string of random digits when looking at the decimals of pi, my mind is able to “chunk” groups of these numbers spontaneously into meaningful visual images that constitute their own hierarchy of associations.
Using your imagination is one very good way to improve your own memory. For example, actors who have to remember hundreds or even thousands of lines of a script do so by actively analyzing them and imagining the motivations and goals of their characters. Many also imagine having to explain the meaning of their lines to another person, which has been shown to significantly improve their subsequent recall.
Here is another tip from my book. Researchers have found that you are more likely to remember something if the place or situation in which you are trying to recall the information bears some resemblance—color or smell, for example—to where you originally learned it. A greater awareness therefore of the context in which we acquire a particular piece of information can help improve our ability to remember it later on.
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