Memory span as a measure of individual differences in memory capacity

Two experiments were carried out to investigate whether the immediate digit span measure traditionally used in the assessment of individual differences in cognition is a good predictor of performance on other memory tasks. In the first experiment, it was found that subjects’ digit spans were not significantly related to their performances on either short-term or longterm memory tasks, or to theoretical measures of their memory store capacities. Memory for the temporal occurrence of events, however, proved to be positively correlated with digit span. A second experiment confirmed that digit span was correlated with memory for the temporal occurrence of events, but not with item memory. Thus it was concluded that an individual’s digit span reflects his ability to retain information about the order of a sequence of events rather than the capacity of his short- or long-term memory.