Working Memory

Working memory is the term used to describe the information one is thinking about at any particular moment. That information keeps changing, and the amount one holds in mind in this way at any moment is quite small compared to the vast amount of information in one's permanent memory storage system in the brain. The concept of working memory has become one of the most important and often-used concepts in the field of psychology, as it helps a great deal in explaining what tasks are easy or hard for individuals to carry out. There are consequently thousands of articles on various aspects of working memory.

The term working memory was suggested in 1960 in a book by George Miller and his colleagues, and the concept was made popular 14 years later in a book chapter by Alan Baddeley and Graham Hitch. The idea behind the term is that there are various kinds of mental work such as thinking, problem solving, reasoning, language comprehension and production, and keeping track of changing events (i.e., while watching a baseball game). To do these kinds of mental work, one must hold in mind certain information relevant to the situation. One might need to hold in mind data such as, in baseball, which team is at bat and how many outs there are in the inning or, when doing addition in one's head, the carried digits. One might also need to hold in mind plans such as, when solving an arithmetic problem, the steps to follow or, when running errands, the order in which errands are to be accomplished. The key point is that the amount of information that can be held in working memory is limited. This fact in turn puts limits on how well humans can solve problems, formulate plans in their heads, and so on.

[Page 787]Working memory appears to have various components, but they operate together as an integrated system. For example, there appears to be cross talk such that, if the goals are too complex, one can forget not only goals but data; conversely, if there are many data to be kept in mind, one can forget not only data, but goals.

This entry will include a discussion of many important aspects of working memory, including a comparison with similar concepts and terms, the kinds of studies demonstrating working memory, limits on working memory, theories of working memory, individual and group differences in working memory, and some possible neural and evolutionary reasons why working memory capacity is limited.