There are many techniques for measuring memory. Some methods are highly specialized, either for the purpose of addressing a particular research question or for diagnosing a specific memory dysfunction, but most measurement procedures are variants of the basic techniques described in this entry.

Measures of Recall

Immediate Serial Recall: Memory Span

In the most commonly used version of this task, a randomly ordered sequence of digits (e.g., 4-7-8-2-5-9) is read once to the participant, who is required to repeat them in the same order. The resulting measure is known as the digit span, defined as the number of digits that can be repeated in the correct order without error. An immediate difficulty is that an individual's performance may fluctuate slightly from one occasion to the next, six digits being correctly repeated on one occasion, for example, and seven on...