Working memory (or "WM") is the system we use to keep information immediately available. We use it when we perform calculations in our heads, track the meaning of a conversation, and remember what we're supposed to do next.
As I explain elsewhere, the capacity of a child's WM affects his or her ability to follow directions, learn to read, excel in mathematics, and achieve in school.
Can we help kids expand this capacity?
Researchers have tested computer-based memory games to see if intense, repetitive practice can boost children's WM skills. These computer games are effective, insofar as they help kids perform better on very similar, computer-based tasks.
But the improvements don't seem to generalize to WM challenges in the real world. After training, kids experience little or no improvement in academic performance (Sala and Gobet 2017; Shiphead et al 2012).
The same may be said for adults (Melby-Lervåg et al 2013), and the lackluster findings apply not only to real-world working memory function, but also to fluid intelligence.
Despite early hopes that working memory games could boost I.Q. scores (Jaeggi et al 2008), the best-designed studies have failed to replicate this effect (Melby-Lervåg et al 2016).
So the computer-based memory game solution hasn't panned out. But that doesn't mean it's a dead-end. Future research may discover new ways to train WM skills -- ways that transfer to specific academic tasks, like decoding a text, or doing arithmetic.
Meanwhile, there is still a lot that adults can do to help children improve WM performance.
This includes supportive strategies in the classroom, which I discuss at the end of the article, "Working memory: What every parent needs to know".
And it includes becoming more savvy about the things that affect everyday performance. Here are seven evidence-based tips for helping children reach their full potential.
We don't use WM in a vacuum. There is always something going on in the background, and that background affects us. Internal sensations and environmental distractions compete for our attention, and we use some of our working memory resources to monitor this stream of information.
This may explain why people experience dips in WM performance when they are uncomfortable, ill, or in pain (Smith et al 2012; Hood et al 2013; Sellaro et al 2015).
People also experience temporary deficits when they detect an unpleasant odor, or notice another person's direct gaze (Martin and Chaudry 2014; Wang and Apperly 2017).
Even something as simple as walking across a crossing a threshold -- into a new room -- can make you forget your purpose. Why did I come here? Was I going to fetch something? Or close a window? The change of scene seems to wipe out the information we were trying to keep in our consciousness. The temporary contents of our mental workspace are lost (Horner et al 2016).
Such are the findings of experiments on adults. What must it be like for young children? Their brains haven't yet developed the attention skills of older people. It's harder for them to filter out irrelevancies, and focus.
So if we want kids to perform demanding WM tasks, we need reduce distractions to a minimum, and make allowances when they aren't feeling well.
When we worry, we use up precious working memory. It's as if information related to our worries creeps into our limited mental workspace, leaving less room for us to think about other things.
The effects are more pronounced if you are particularly prone to worrying, or suffer from an anxiety condition (Sari 2017; Stout et al 2015; Vytal et al 2016), and even young children are not immune.
Anxiety symptoms have been linked with poorer WM performance in preschoolers (Visu-Petra et al 2014).
Moreover, individuals have anxieties that affect their working memory for specific tasks, like solving mathematical problems (Shi and Liu 2016). In fact, poor WM performance can itself be a trigger for worries, creating a snowball effect (Tresize and Reeve 2016).
Can we improve WM performance by treating our anxieties? Research supports the idea.
One useful technique is to write candidly about your worries and anxieties, and explore the reasons for them. The therapeutic effects of this approach, called "expressive writing," has been shown to improve WM capacity -- sometimes for weeks afterward (Klein and Boals 2001; Yogo and Fujihara 2008; Park et al 2014). And it can lead to higher scores on academic exams (Ramirez and Beilock 2011).
Another approach is to train your mind to resist intrusive, distressing thoughts. This is one of the goals of mindfulness meditation, a traditional Buddhist practice. Research suggests that mindfulness meditation can reduce anxiety (Goyal et al 2014), and a recent study of middle school students hints at working memory benefits as well (Quach et al 2016).
What about anxiety in young children? Kids too young to try expressive writing, or enroll in a middle school meditation course?
Warm, responsive parenting is always helpful, and so is "emotion coaching" -- teaching children about their emotions through sensitive conversations and problem-solving sessions. But it's important to recognize that some children will need more support than others -- more reassurance, and more help learning strategies that build confidence. And we should watch out for common mistakes.
When we are dismissive or critical of children's anxieties, kids get the message that we're unsupportive. When we are overprotective, children get the message that their anxieties are justified. Either way, kids don't get the coaching they need to build skills and overcome with fears (Hurrel et al 2017).
If you think your child suffers from anxiety problems, discuss your concerns with your medical provider, and ask about programs for improving symptoms. Researchers have developed a number of programs for parents struggling with anxious children (e.g., Fox et al 2012; Chronis-Tuscano et al 2015; Creswell et al 2017; Morgan et al 2017). They draw on principles of cognitive behavioral therapy -- which has a good track record in improving anxiety symptoms in kids -- and typically take only 6-8 weeks to complete.
What happens when we feel we are being unfairly judged? Snubbed? Targeted for social discrimination? These situations are stressful, and they can impair WM performance.
You might wonder if stress hormones are directly responsible, but that doesn't seem to be the problem. Instead, it appears that our minds become partially preoccupied with the job of restraining our negative emotional responses. And that uses up precious WM (van Ast et al 2016).
For example, experiments show that being reminded of a derogatory stereotype -- concerning one's own race, sex, or other group membership -- can cause immediate, measurable reductions in WM capacity (Pennington et al 2016).
People naturally want to prove the stereotype wrong, and to succeed, they know they will need to control their negative emotions. It's hard to be at the top of your game if you're feeling anxious, defensive, or outraged.
So people end up diverting valuable working memory resources to keeping these emotions under control, leaving less WM capacity for performing the task at hand (Johns et al 2008).
How early in life might a child's WM performance be affected by "stereotype threat"?
That's not entirely clear, but experiments in the United States suggest that boys as young as 7 years perform more poorly on tests of reading, writing, and mathematics when they are reminded of the "girls are better students" stereotype (Hartley and Sutton 2013).
And recent research conducted by Kate Wegmann suggests that kids between the ages of 7 and 11 years have no trouble identifying the threats posed by derogatory ethnic stereotypes about academic ability (Wegmann 2017).
It seems likely, then, that school-aged kids experience WM impairments triggered by stereotypes about sex and ethnicity.
There is also evidence that kids experience WM impairments triggered by stereotypes about body weight and obesity (Guardabassi and Tomasetto 2020).
All this might sound very discouraging. But researchers have identified effective strategies for countering stereotype threat, which you can read about here.
When you don't get enough, WM performance suffers.
It's not surprising that performance on working memory tasks would deteriorate when we're tired or sleepy. If we're physically uncomfortable, that's a distraction. If we're sleepy enough, we might also suffer from spontaneous lapses of consciousness, called microsleeps. Experiments show that one night of sleep deprivation results in immediate impairments in working memory (e.g., Kopasz et al 2010; deBruin et al 2017).
What's more interesting -- and disturbing -- is the idea that chronic sleep troubles might interfere with the development of WM capacity.
When researchers have administered WM tests to different populations, they've found links between an individual's test scores and his or her habitual patterns of sleep (Sciberras et al 2015; Kopasz et al 2010).
For instance, when researchers tested WM in more than 1700 Australian first graders, they found strong links between verbal working memory difficulties and parent-reported poor sleep (Cho et al 2015).
Is it possible that we could boost a child's WM capacity -- and academic performance -- by making sure he or she is getting enough sleep?
I haven't found any experimental research on the topic. But in a recent study of college undergraduates, students randomly assigned to add an afternoon nap to their schedule experienced better WM performance immediately afterwards (Lau et al 2015).
For help troubleshooting sleep problems in children, see these tips.
What happens when somebody tells you a new telephone number? Until you can make a record of it, you keep the memory alive by repeating the information back to yourself. You might speak out loud, or repeat the numbers silently in your head. But either way, you're talking to yourself, and that repetition is called "verbal rehearsal."
Rehearsal is essential for some WM tasks (Lucidi et al 2016), and kids discover its value early in life. Young children often talk to themselves in ways that help them stay on task (Alderson-Day and Fernyhough 2015), and they may use verbal rehearsal to keep information active in working memory (Fatzer and Roebers 2012).
Yet children don't always take full advantage of this strategy, which might explain some individual differences. Among 5- and 6-year-olds, researchers have found that the use of self-regulatory speech is linked with better problem-solving (Fernyhough and Fradley 2005; Winsler and Naglieri 2003).
And research suggests that many kids -- including young children, and those with low working memory capacity for their age -- may benefit from being encouraged to voice, or repeat back, key information (Müller et al 2009; Gatherole and Alloway).
So it makes sense to encourage kids to make use of verbal rehearsal, and be mindful of what happens when we do the opposite. Asking kids to suppress their self-regulatory speech (e.g., "work silently at your desk") could have a negative impact on performance. When researchers asked school kids to solve a visual-spatial puzzle that required planning ahead, they found that children performed worse when they were instructed not to speak aloud (Lidstone et al 2010).
Many people find it natural to gesture as they speak. Is this just a lot of hand waving, or does it serve a purpose?
Decades of experimental research provides an answer: Gestures can help us learn and recall information. And it also appears to help people struggling with WM limitations.
Gesturing helps adults stay on track when they perform visuo-spatial tasks that tap working memory (Wu and Coulson 2014; Morsella and Krauss 2004). It also seems to help adults perform tasks that require verbal WM, especially if they have lower WM capacities to begin with (Gillespie et al 2014).
What about kids? They, too, seem to benefit from gestures.
When Susan Goldin-Meadow and her colleagues asked children to perform a working memory task, kids who spontaneous gestured during the process achieved more (Goldin-Meadow et al 2001).
Moreover, other research indicates that kids learn mathematics more readily when they are asked to perform relevant gestures during a lesson (Cook et al
2006). And the effect is passive, too: Kids learn better when their instructors include relevant gestures in their speech (e.g., Cook et al 2017).
Does this mean gesturing helps everyone? Not necessarily. But researchers suspect that gestures can reduce demands on WM. And it's clear that suppressing natural gestures can put kids at a disadvantage. When researchers prohibit children from gesturing, they perform worse on WM tests (e.g., Pine et al 2007).
To read more about how gestures help kids learn and reason, see this article.
When kids absorb more knowledge, they develop more efficient ways of juggling information.
Nobody has an objectively large WM capacity. In experiments, adults can keep only a few distinct pieces of information in focus at once -- about 3 to 5 items (Cowan 2001). In studies of 7- and 8-year-old children, the average WMC is just 1-2 items (Riggs et al 2006).
But these are the limits for information that is abstract or disconnected what we already know. When people are presented with familiar information, their performance improves.
For instance, if I briefly flashed a sequence of twelve, apparently random letters at you, and then asked you to repeat them back, you'd find that very difficult, if not impossible:
But notice how much easier it is when the letters aren't random, but instead a series of meaningful acronyms:
CIA UFO PHD IBM
Your underlying working memory capacity hasn't expanded. But your performance has.
Your prior knowledge of things like the Central Intelligence Agency helps you compress many disparate units of information into fewer, meaningful chunks.
The chunks might contain three letters each, but your working memory no longer has to keep track of all twelve letters. Instead, you probably remember each chunk as a distinct item, and rapidly retrieve information from long-term memory when I ask you to reel off the letters in the correct sequence (Cowan 2016).
So background knowledge helps you remember a sequence of letters. What else can it do? A lot.
For example, background knowledge reduces demands on working memory when we read (Miller et al 2006; Soederberg Miller 2009), allowing us to process more complex sentence structure.
And one key reason why kids perform more poorly on WM tests is because they lack the background information that adults take for granted. When researchers have created WM tests that virtually eliminate the possibility of prior knowledge, adult WM performance is sometimes reduced to what we observe in children (Cowan 2016).
Moreover, there is evidence that kids acquire better WM skills as a function of time spent in school. In a study tracking the progress of approximately 1700 first graders, researchers found that WM performance increased steadily over the course of the school year.
Was this merely because the children were getting older? Apparently not, because when researchers controlled for each student's age, they discovered it was the duration of schooling that mattered. Time spent in school, not age, predicted increases in WM performance (Roberts et al 2016). This is consistent with the idea that kids are learning things that help them organize, chunk, and encode information.
Of course, that doesn't mean that background knowledge is the only important factor. On some laboratory tests, children show dramatic gains over time -- even when the featured items are totally unfamiliar (Cowan et al 2015).
But in everyday life, you encounter a mix of information, familiar and unfamiliar. And having more background information gives you an advantage. It helps you reduce demands on working memory, so you're less likely to get overwhelmed.
It's a powerful argument for cranking up your curiosity and learning more about the world. Being an avid reader, a consumer of interesting facts, or a collector of new vocabulary may pay off in ways that go beyond the accumulation of information in long-term memory. It may actually help you repackage incoming data, freeing up crucial WM resources. You're left with more WM to think and solve problems with.
By helping kids discover intellectual passions and soak up new information, we are laying the groundwork for long-term improvements in working memory performance.
For more information on this subject, see this guide to working memory. In addition, check out these related topics:
Alderson-Day B, Fernyhough C. 2015. Inner Speech: Development, Cognitive Functions, Phenomenology, and Neurobiology. Psychol Bull. 2015 Sep; 141(5): 931–965.
Brown A, Creswell C2, Barker C, Butler S, Cooper P, Hobbs C, Thirlwall K. 2017. Guided parent-delivered cognitive behaviour therapy for children with anxiety disorders: Outcomes at 3- to 5-year follow-up. Br J Clin Psychol. 56(2):149-159.
Cho M, Quach J, Anderson P, Mensah F, Wake M, Roberts G. 2015. Poor sleep and lower working memory in grade 1 children: cross-sectional, population-based study. Acad Pediatr. 15(1):111-6.
Cook SW, Friedman HS, Duggan KA, Cui J, Popescu V. 2017. Hand Gesture and Mathematics Learning: Lessons From an Avatar. Cogn Sci. 41(2):518-535.
Cowan N. 2016. Working Memory Maturation: Can We Get at the Essence of Cognitive Growth? Perspect Psychol Sci. 11(2):239-64.
Cowan N, Ricker TJ, Clark KM, Hinrichs GA, Glass BA. 2015. Knowledge cannot explain the developmental growth of working memory capacity. Dev Sci. 18(1):132-45.
Creswell C, Violato M, Fairbanks H, White E, Parkinson M, Abitabile G, Leidi A, Cooper PJ. 2017. Clinical outcomes and cost-effectiveness of brief guided parent-delivered cognitive behavioural therapy and solution-focused brief therapy for treatment of childhood anxiety disorders: a randomised controlled trial. Lancet Psychiatry. 2017 May 17. pii: S2215-0366(17)30149-9. doi: 10.1016/S2215-0366(17)30149-9. [Epub ahead of print]
de Bruin EJ, van Run C, Staaks J, Meijer AM. 2017. Effects of sleep manipulation on cognitive functioning of adolescents: A systematic review. Sleep Med Rev. 32:45-57.
Fatzer ST and Roebers CM. 2012. Language and executive functions: The effect of articulatory suppression on executive functioning in children. Journal of Cognition and Development 13: 454–472.
Fernyhough C and Fradley E. 2005. Private speech on an executive task: Relations with task difficulty and task performance. Cognitive Development 20: 103–120.
Fox JK, Masia Warner C, Lerner AB, Ludwig K, Ryan JL, Colognori D, Lucas CP, Brotman LM. 2012. Preventive intervention for anxious preschoolers and their parents: strengthening early emotional development. Child Psychiatry Hum Dev.43(4):544-59.
Gathercole SE. 1998. The development of memory. J Child Psychol Psychiatry. 39(1):3-27.
Gillespie M, James AN, Federmeier KD, Watson DG. 2014. Verbal working memory predicts co-speech gesture: evidence from individual differences. Cognition. 132(2):174-80
Goyal M, Singh S, Sibinga EM, Gould NF, Rowland-Seymour A, Sharma R, Berger Z, Sleicher D, Maron DD, Shihab HM, Ranasinghe PD, Linn S, Saha S, Bass EB, Haythornthwaite JA. 2014. Meditation programs for psychological stress and well-being: a systematic review and meta-analysis. JAMA Intern Med. 174(3):357-68.
Guardabassi V and Tomasetto C. 2020. Weight status or weight stigma? Obesity stereotypes-Not excess weight-Reduce working memory in school-aged children. J Exp Child Psychol. 189:104706.
Hartley BL and Sutton RM. 2013. A stereotype threat account of boys' academic underachievement. Child Dev. 84(5):1716-33.
Hood A, Pulvers K, Spady TJ. Timing and gender determine if acute pain impairs working memory performance. J Pain. 14(11):1320-9.
Horner AJ, Bisby JA, Wang A, Bogus K, Burgess N. 2016. The role of spatial boundaries in shaping long-term event representations. Cognition. 154:151-64.
Hurrell KE, Houwing FL, Hudson JL. 2017. Parental Meta-Emotion Philosophy and Emotion Coaching in Families of Children and Adolescents with an Anxiety Disorder. J Abnorm Child Psychol. 45(3):569-582.
Johns M, Inzlicht M, Schmader T. 2008. Stereotype threat and executive resource depletion: examining the influence of emotion regulation. J Exp Psychol Gen. 137(4):691-705.
Klein K and Boals A. 2001. Expressive writing can increase working memory capacity. J Exp Psychol Gen. 130(3):520-33.
Kopasz M, Loessl B, Hornyak M, Riemann D, Nissen C, Piosczyk H, Voderholzer U. 2010. Sleep and memory in healthy children and adolescents - a critical review. Sleep Med Rev. 14(3):167-77.
Lau EY, Wong ML, Lau KN, Hui FW, Tseng CH. 2015. Rapid-Eye-Movement-Sleep (REM) Associated Enhancement of Working Memory Performance after a Daytime Nap. PLoS One. 10(5):e0125752
Lidstone JS, Meins E, Fernyhough C. 2010. The roles of private speech and inner speech in planning during middle childhood: evidence from a dual task paradigm. J Exp Child Psychol. 107(4):438-51.
Lucidi A, Langerock N, Hoareau V, Lemaire B, Camos V, Barrouillet P. 2016. Working memory still needs verbal rehearsal. Mem Cognit. 44(2):197-206
Martin GN and Chaudry A. Working memory performance and exposure to pleasant and unpleasant ambient odor: is spatial span special? Int J Neurosci. 124(11):806-11.
Melby-Lervåg M, Redick TS, Hulme C. 2016. Working Memory Training Does Not Improve Performance on Measures of Intelligence or Other Measures of "Far Transfer": Evidence From a Meta-Analytic Review. Perspect Psychol Sci.11(4):512-34.
Miller LM, Cohen JA, Wingfield A. 2006. Contextual knowledge reduces demands on working memory during reading. Mem Cognit. 34(6):1355-67.
Morgan AJ, Rapee RM, Salim A, Goharpey N, Tamir E, McLellan LF, Bayer JK. 2017. Internet-Delivered Parenting Program for Prevention and Early Intervention of Anxiety Problems in Young Children: Randomized Controlled Trial. J Am Acad Child Adolesc Psychiatry. 56(5):417-425.e1.
Morsella E, Krauss RM. 2004. The role of gestures in spatial working memory and speech. Am J Psychol. 117(3):411-24.
Müller U., Jacques S., Brocki K., & Zelazo P. D. (2009). The executive functions of language in preschool children In Winsler A., Fernyhough C., & Montero I. (Eds.), Private speech, executive functioning, and the development of verbal self-regulation (pp. 53–68). Cambridge, UK: Cambridge University Press;
Park D, Ramirez G, and Beilock SL. 2014. The role of expressive writing in math anxiety. J Exp Psychol Appl. 20(2):103-11.
Pennington CR, Heim D, Levy AR, Larkin DT. 2016. Twenty Years of Stereotype Threat Research: A Review of Psychological Mediators. PLoS One. 11(1):e0146487.
Pine KJ, Bird H, and Kirk E. 2007. The effects of prohibiting gestures on children's lexical retrieval ability. Dev Sci. 10(6):747-54.
Quach D, Jastrowski Mano KE, Alexander K. 2016. A Randomized Controlled Trial Examining the Effect of Mindfulness Meditation on Working Memory Capacity in Adolescents. J Adolesc Health. 58(5):489-96.
Ramirez G and Beilock SL. 2011. Writing about testing worries boosts exam performance in the classroom. Science. 331(6014):211-3.
Riggs KJ, McTaggart J, Simpson A, Freeman RP. 2006. Changes in the capacity of visual working memory in 5- to 10-year-olds. J Exp Child Psychol. 295(1):18-26.
Roberts G, Quach J, Mensah F, Gathercole S, Gold L, Anderson P, Spencer-Smith M, Wake M. 2015. Schooling duration rather than chronological age predicts working memory between 6 and 7 years: Memory Maestros Study. J Dev Behav Pediatr. 36(2):68-74.
Sala G and Gobet F. 2017. Working memory training in typically developing children: A meta-analysis of the available evidence. Dev Psychol. 53(4):671-685.
Sari BA, Koster EHW, Derakshan N. 2017. The effects of active worrying on working memory capacity. Cogn Emot. 31(5):995-1003.
Sciberras E, DePetro A, Mensah F, Hiscock H. 2015. Association between sleep and working memory in children with ADHD: a cross-sectional study. Sleep Med. 16(10):1192-7.
Sellaro R, Hommel B, Manaï M, Colzato LS. 2015. Preferred, but not objective temperature predicts working memory depletion. Psychol Res. 79(2):282-8.
Shi Z and Liu P. 2016. Worrying Thoughts Limit Working Memory Capacity in Math Anxiety. PLoS One. 11(10):e0165644.
Smith AP. 2012. Effects of the common cold on mood, psychomotor performance, the encoding of new information, speed of working memory and semantic processing. Brain Behav Immun. 26(7):1072-6.
Soederberg Miller LM1. 2009. Age differences in the effects of domain knowledge on reading efficiency. Psychol Aging. 24(1):63-74.
Stout DM, Shackman AJ, Johnson JS, Larson CL. 2015. Worry is associated with impaired gating of threat from working memory. Emotion. 15(1):6-11.
Tresize K and Reeve SA. 2016. Worry and working memory influence each other iteratively over time. Cogn Emot. 2016;30(2):353-68.
van Ast VA, Spicer J, Smith EE, Schmer-Galunder S, Liberzon I, Abelson JL, Wager TD. 2016. Brain Mechanisms of Social Threat Effects on Working Memory. Cereb Cortex. 26(2):544-556.
Visu-Petra L, Stanciu O, Benga O, Miclea M, Cheie L. 2014. Longitudinal and concurrent links between memory span, anxiety symptoms, and subsequent executive functioning in young children. Front. Psychol. 5:443.
Vytal KE, Arkin NE, Overstreet C, Lieberman L, Grillon C. 2016. Induced-anxiety differentially disrupts working memory in generalized anxiety disorder. BMC Psychiatry. 16:62.
Wang JJ and Apperly IA. 2017. Just one look: Direct gaze briefly disrupts visual working memory. Psychon Bull Rev. 224(2):393-399.
Wegmann KM. 2017. "His Skin Doesn't Match What He Wants to Do": Children's Perceptions of Stereotype Threat. Am J Orthopsychiatry. 2017 Mar 9. doi: 10.1037/ort0000238. [Epub ahead of print]
Winsler A and Naglieri J. 2003. Overt and covert verbal problem-solving strategies: Developmental trends in use, awareness, and relations with task performance in children aged 5 to 17. Child Development 74: 659–678.
Wu YC and Coulson S2. 2014. Co-speech iconic gestures and visuo-spatial working memory. Acta Psychol (Amst). 153:39-50.
Yogo M and Fujihara S. 2008. Working memory capacity can be improved by expressive writing: a randomized experiment in a Japanese sample. Br J Health Psychol. 13(Pt 1):77-80.
Image of boys playing with puzzles by US Army
Image of worried girl by Andy / flickr
Image of mother and daughter hugging my US Dept. of Education
Image of boy sleeping by Woodley Wonderworks / flickr
Image of mother and girl working at desk by AZemdega / istock
Image of toddler gesturing at father by David R Tribble /wikimediacommons
Image of girl reading magazine outdoors by Fiona Graham WorldRemitCommons / flickr
Image of kids reading on bed by Niki Duggan / wikimedia commons
Content last modified 12/19