How to improve 'number' memory

Saturday, 07 July 2007

University of Melbourne Our survival depends on effectively processing numerical information – forgetting a pin number can be more than a little embarrassing. How do we remember postcodes and mobile phone numbers? What are the limits of our ‘number’ memory and how can we improve it? Performance on ‘digit span’ tests, which assess the ability to remember sequences of single digit numbers, show that most adults can remember between six and 10 numbers. Nevertheless, some researchers have shown that we are more adept at remembering sequences of numbers than previously thought. W G Chase gave students a digit span test daily for eight months, increasing the number of to-be-remembered digits as performances improved. At the conclusion of the study many participants could remember almost 80 digits. J Smith obtained similar results with older adults (70 years+). How were participants able to perform such memory feats? Many individuals used techniques that made the to-be-remembered numbers meaningful. One student in Chase’s study – a competitive swimmer – associated number sequences with swimming event times, making them more meaningful and easier to recall. Unfortunately, not everyone is able to remember numbers as easily. In research at Melbourne we have been investigating the abilities of individuals who are unable to process numerical information, but otherwise have normal intelligence. So-called ‘dyscalculia’ is estimated to affect 6–10 per cent of people. Individuals with dyscalculia depend on special techniques to survive in the numerical world.