Article 5Training Working Memory: Why andHowMake your working memory work for you.by William Klemm, D.V.M., Ph.D., is a Professor of Neuroscience atTexas A&M University.Psychology Today, March 26, 2012Working memory refers to the memory you can consciously hold in yourmind at any one instant—such as a phone number you just looked up. Mostpeople can only hold about four totally independent items in their workingmemory.Working memory relates to intelligence. The reason is that thinkinginvolves streaming into the brains "thought engine" chunks of informationheld in working memory. The working memory streams in, much like aWeb video streams into your computer. The more you can hold in workingmemory, the more information the brain has to think with—that is, thesmarter it can be.IQ is not fixed. It improves dramatically in the early school years in allchildren. Moreover, a recent study shows that both verbal and non-verbalIQ can change (for better or worse) in teenagers.Educators have known for some time that it is possible to train ADHDchildren to have better working memories, and in the process improve theirschool performance. The idea that working memory capacity might beexpanded by training normal children has not yet caught on. Test-driventeaching in U.S. schools teaches students what to learn, not how to learn.Researchers in Japan recently tested whether a simple working memorytraining method could increase the working memory capacity of children.While they were at it, they tested for any effect on IQ. Children ages 6-8were trained 10 minutes a day each day for two months. The training task
to expand working memory capacity consisted of presenting a digit or aword item for a second, with one-second intervals between items. Forexample, a sequence might be 5, 8, 4, 7, with one-second intervals betweeneach digit. Test for recall could take the form of "Where in the sequencewas the 4?" or "What was the 3rd item?" Thus students had to practiceholding the item sequence in working memory. With practice, the trainersincreased the number of items from 3 to 8.After training, researchers tested the children on another working memorytask. Scores on this test indicated in all children that working memorycorrelated with IQ test scores. When first graders were tested forintelligence, the data showed that intelligence scores increased during theyear by 6% in controls, but increased by 9% in the group that had beengiven the memory training. The memory training effect was even moreevident in the second graders, with a 12% gain in intelligence score in thememory trained group, compared with a 6% gain in controls. As might beexpected, the lower IQ children showed the greatest gain from memorytraining.I recently found a paper revealing lasting improvements in brain functionwere produced in healthy adults by only five weeks of practice on threeworking-memory tasks involving the location of objects in space, using atraining program called CogMed. Similar results have been reported byother investigators.Another study provides strong evidence that increasing adult workingmemory capacity will raise their IQ. Subjects, young adults were trained ona so-called dual N-back test in which subjects were asked to recall a visualstimulus that they saw two, three or more stimulus presentations in the past.As performance improved with each block of trials, the task demands wereincreased by shifting from two-back to three, then three to four, etc. Dailytraining took about 25 minutes.The investigators found working memory training improved scores on theIQ test. Moreover, the effect was dose-dependent, in that intelligencescores increased in a steady straight-line fashion as the number of trainingsessions increased from 8 to 12 to 17 to 19.Advances in this arena of raising IQ in teenagers and adults may comefaster now that we have some many published reports that working
memory capacity can indeed be expanded by training. The trick is infinding which approaches work best. Currently, we believe that workingmemory can be expanded by attentiveness training, music, and certaingame environments. Actually, I believe demanding education can do thesame thing.Various techniques are reported in the research literature, and the bestresults seem to come from n-back methods. One study by Verhaeghen andcolleagues show that memory span could be increased from one to foursteps back with 10 hours (1 hr/session) of N-back training.A whole cognitive enhancement industry is flourishing. The idea of brainfitness software is that playing mentally challenging games will make yousmarter. This is not necessarily true. Several recent reviews suggest thatsuch games do little. I can only recommend with some certainty thosegames that focus on expanding working memory capacity, and even here,one should not expect too much. I know about three such programs,MindSparke, Cogmed, and Jungle Memory. I have no personal experienceor financial interest in any of these, but each has the potential to be helpful,especially in kids or adults with attention deficit.Training Working Memory Can Be FunBiological reward comes from the release of the neurotransmitter,dopamine. Dopamine release is promoted by performing working memorytasks, which suggests that working memory tasks are actually rewarding. Inthe study of human subjects by Fiona McNab and colleagues in Stockholm,human males (age 20-28) were trained for 35 minutes per day for fiveweeks on working memory tasks with a difficulty level close to theirindividual capacity limit. After such training, all subjects showed increasedworking memory capacity. Functional MRI scans also showed that thememory training increased the cerebral cortex density of dopamine D1receptors, the receptor subtype that mediates feelings of euphoria andreward.Some games that are fun to play may also help working memory. The mostobvious example is chess. To play chess well, you have to learn to expandworking memory capacity to hold a plan for several offensive moves whileat the same time holding a memory of how the opponent could respond toeach of the moves. Not surprisingly there are studies showing that IQ
scores can go up after several months of chess playing. Some schools,especially in minority schools in impoverished neighborhoods have seenmarked improvements in school work by students who joined school chessclubs.Students who make good grades feel good about their success. Likewise,people who are "life-long learners" have discovered learning lots of newthings makes them feel good.