working memory

n. Working memory refers to the temporary storage of information that is currently being used in a cognitive task. The concept emerged from studies of a related but simpler concept, short-term memory. The distinction may be clarified by comparing two memory tasks. In a simple span test, which is often used to assess short-term memory, individuals are given a series of items (e.g., digits). A person's memory span is the number of items that can be reliably recalled in the correct order.

In contrast, a complex span test requires participants to retain some information while performing another cognitive task. For example, an individual is asked to perform the following arithmetic calculations while also retaining the corresponding word:

(5 × 5) + 1 = 26 cat
(8/4) + 7 = 9 truck

The complex memory span is the number of words remembered while successfully performing the second task.

Complex span scores predict verbal SAT scores in college students as well as young children's reading and academic success. In contrast, the simple span score is not correlated with such tasks. The key difference is that complex scan tests require individuals to perform storage and processing functions simultaneously, whereas simple span tests are based on storage only. It is thought that working memory consists of a limited pool of resources, and that storage and processing functions compete for resources. – DWC