So, after our in-depth exploration of inhibitory control and all it means, we are ready to plunge into the next construct that is typically a part of Executive Function. This process is the “updating” process, or working memory.
What is Working Memory?
Working memory is the ability to keep information in mind – and manipulate it. The manipulation part is important, because just keeping information in your head is called “short-term memory”. The classic example of short-term memory is looking up a phone number in the phone book and then repeating it over and over until you get to the phone and can dial it. It sounds like it’s something from the Stone Age, but when I was an undergraduate student that was the example that was used.
Measuring Working Memory
A classic working memory measure is the Backward Digit Span, a task taken from an IQ test. The experimenter says a string of digits, and the participant is asked to repeat it in a reversed order. For example, if the experimenter said 5-8-2, a correct answer would be 2-8-5. The idea is that you have both to remember the digits and manipulate the information (reverse the order). However, young children (3-year-olds) find this “game” very difficult. Even when there is a puppet that demonstrates how to do it, most of the studies I was involved with and in which we used backwards digit span, 3- and many 4-year-olds were really bad at this. In general, the older kids get, the better they are at working memory tasks in terms of capacity. That means that they can remember more pieces and manipulate them, not necessarily that they can do something different with those pieces.
Why is Working Memory an Executive Function?
The original structure of working memory included a “central executive” and two (recently three) sub-systems that are “enslaved” to the central executive. The two systems included a phonological loop (an auditory system – think about the example of the phone number) and a visual sketchpad to keep visual and spatial information. The idea is that the central executive manages those slave systems. So, according to that theory, the central executive does the “manipulation” part, and the slave systems do the “remembering” part.
The truth is that working memory is probably a process all on its own. If you recall, Executive Functions are processes that enable goal-directed behaviour. If working memory is included in this umbrella then other processes should be included as well. Take language, for example. You really can’t do any goal-directed behaviour without language in the same way that you can’t do any goal-directed behaviour without working memory. But working memory plays a role in all kinds of behaviours, and is probably a more “general” cognitive skill.
I know this was kind of technical, but working memory is an important component. Next time I’ll talk about cognitive flexibility, the most awesome process of all (and my research focus).
This time I would love to hear what you thought about the post. Too technical? Too simplified? Too boring?