Working memory, also known as WM, is a bundle of mechanisms that allows us to maintain a train of thought.
It's what we use to plan and carry out an action -- the mental workspace where we manipulate information, crunch numbers, and see with our "mind's eye" (Cowan 2010; Miller et al 1960).
Can you add together 23 and 69 in your head?
Remember a list of grocery store items without writing them down?
Recall the seating arrangements of a dinner party after a brief glimpse at the table?
These tasks tap WM, and whether or not you succeed depends on your working memory capacity, or WMC.
People with larger capacities can juggle more information at once. This helps them process information more quickly, and the benefits are well-documented. People with higher-than-average WMC are more likely to excel in the classroom.
For example, when researchers have tracked the development of primary school children, they've found that early gains in visuospatial WM predict later achievement in mathematics (Li and Geary 2013; Li and Geary 2017). Working memory is also predictive of language skills, like the ability to keep track of the ideas presented in a long or complex sentence (Zhou et al 2017).
On the flip side, individuals with poor WM skills at a disadvantage. They are more likely to struggle with mathematics and reading. They may also struggle with following spoken directions.
Please give me your drawing, then put away the crayons and clean up your desk.
It might sound easy to you. But for younger children -- who have lower capacities than adults do -- these instructions may cause an information overload.
The same thing is true for older kids who have low WMC for their age. There is too much to juggle, so they lose track of what they are supposed to do.
WM seems to be a basic component of fluid intelligence. It affects how kids learn. It also influences how kids perform on tests, including achievement tests and IQ tests.
But we can’t equate WM with overall intelligence. For instance, working memory isn’t the same thing as IQ.
Some kids perform well on IQ tests and yet have relatively mediocre WM skills (Alloway and Alloway 2010). How is this possible? Tests like the Wechsler Intelligence Scale for Children (WISC) have distinct subtests. Some specifically target WM, others don’t.
Moreover, there are components of intelligence -- like rationality -- that go largely unmeasured by IQ tests, and don't correlate with WMC. In recent experiments, researchers found that individual differences in WMC had no effect on whether or not people fall prey to belief bias, a common failure of logical reasoning (Robinson and Unsworth 2017).
Finally, it's possible to have very selective WM deficits, which can lead to selective deficits in intellect performance. For example, children diagnosed with developmental dyscalculia -- a learning disability relating to arithmetic -- perform normally on many tests of WMC, except one: They are less likely to remember the precise order of items on a list (Attout and Majerus 2015).
In addition to dyscalculia, reading problems are also linked with WM. Studies suggest that about 70% of kids with learning difficulties in reading have poor WM skills (Gathercole and Alloway 2007).
Compared with typically developing children, kids who have been diagnosed with attention deficit disorder are more likely to have WM difficulties (Kuhn et al 2016; Alderson et al 2016). But it's possible to have poor WM skills and not fit all the criteria for an attention deficit disorder diagnosis.
Yes. When researchers have administered the same WM tests across age, they've found evidence for steady improvement, with adults performing almost twice as well as young children (Gatherole et al 2004; Gatherole and Alloway 2007).
For example, in WM tasks dependent on tracking items in a briefly-presented visual array, adults remember approximately 3 or 4 objects (Cowan 2016). Five-year-olds recall only half as many (Riggs et al 2006).
Researchers estimate that 10-15% of school age children are struggling with low WM capacity (Holmes et al 2009; Fried et al 2016). How can we identify them?
A professional diagnosis depends on administering special tests, like Tracy Alloway’s Automated Working Memory Assessment (AWMA), which you can read about here.
But we can also get a good idea of who is struggling by observing everyday behavior. According to Susan Gatherole and Tracey Alloway (2007), the typical child with WM difficulties shows the following signs.
He or she
You might have heard of computer-based memory games that are supposed to enhance WM, or even IQ. Do they actually work?
It depends on what you mean by "work." For example, consider the computer-based training program developed by Cogmed. In one study, researchers identified kids with low WMC, and assigned these children to play a series of computer games designed to challenge their WM skills (Holmes et al 2009). Some of these games included:
For children in a control group, the difficulty level of these tasks remained easy throughout the study. But for kids in the treatment group, the program was adaptive--i.e., they were given progressively more difficult tasks as their performance improved.
After about 6 weeks of training, researchers re-tested the students' working memory skills, and the results were pretty dramatic. While both groups improved, the kids in the adaptive program did much better. Their average gains were 3 to 4 times higher than those of kids in the control group.
But there was a crucial catch: Improvements were found only on tests that closely resembled the training games. And that has been the pattern in other studies.
Training helps people get better at the specific tasks for which they are trained. But it doesn't seem to help people perform better in other areas -- like reading or mathematics. "Far transfer effects" haven't panned out -- not in the largest, best-designed, most carefully controlled studies conducted to date (Sala and Gobet 2017; Melby-Lervåg et al 2016; Shiphead et al 2012).
So if you are interested in improving a child's performance on working memory games, then this type of training is worthwhile. And perhaps someday we'll find out these games deliver long-term benefits that researchers haven't yet been able to detect.
But if you're goal is to help your child in the classroom, it probably makes more sense to target the tasks that are giving him or her trouble.
If a child struggles with mathematics, seek out special training in the relevant mathematical skills -- like counting, number sense, or basic arithmetic calculations (Kyttälä et al 2015).
If a child is having trouble with reading, look for programs that designed for kids who need to build literacy skills (Melby-Lervåg et al 2016).
As Susan Gathercole and Tracey Alloway note, we can help
children compensate for WM limitations in a variety of ways. For example:
And research suggests other tactics too. To get the most from your WMC, you need to understand how it functions. What disrupts WM? What tricks allow people to pack more data in the mental workspace?
For more information, check out these evidence-based tips for improving working memory performance.
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Content last modified 6/2017
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