Working memory
Working memory is the ability to hold a small amount of information in mind, in a readily accessible form, and to work with it. It supports planning, comprehension, reasoning and problem-solving.
What it means in practice
Working memory means holding information in mind and mentally working with it [2]. That makes it different from short-term memory, which is just holding information in mind, and the two separate into different factors in analyses of children, adolescents and adults [2].
The amount a person can hold at once is small. An early estimate put immediate recall at about seven chunks, where a chunk is a meaningful unit [1]. Researchers still debate why: working memory could be limited by how many items it can hold at once, or by how long an item lasts when it is no longer rehearsed or refreshed [1].
One long-standing account is the multicomponent approach, reviewed by Alan Baddeley. Its overall framework has remained relatively stable, while the more specific models built within it have changed [4]. Diamond's review counts working memory as one of three core executive functions, alongside inhibition and cognitive flexibility [2].
Why it matters when reading nootropics research
Researchers use tasks such as the n-back to measure working memory [3]. In the n-back task, a person indicates when the current item is the same as the one shown n trials earlier [3]. It is one of the most popular tasks in brain imaging studies of working memory [3].
Versions of the task differ in what people track, such as the identity or location of verbal or nonverbal items [3]. A meta-analysis of 24 imaging studies in healthy participants found broadly consistent brain activity across n-back versions, and also patterns specific to the process and content being tracked [3]. Check which version a study used when comparing results.
When a trial reports a working memory result, check which task produced it and whether working memory was a planned primary outcome or one of many tests. Diamond's review identifies the relationship between working memory, inhibition and attention as an open controversy [2]. On NootropicsWork, working memory is graded as its own outcome, separate from memory in general and from executive function.
References
- Cowan N. Working Memory Underpins Cognitive Development, Learning, and Education. Educ Psychol Rev. 2014.
- Diamond A. Executive functions. Annu Rev Psychol. 2013.
- Owen AM, McMillan KM, Laird AR, et al. N-back working memory paradigm: a meta-analysis of normative functional neuroimaging studies. Hum Brain Mapp. 2005.
- Baddeley A. Working memory: theories, models, and controversies. Annu Rev Psychol. 2012.