Working memory training
Encyclopedia
Working memory training is any endeavor intended to increase a person's working memory
, a core cognitive ability. The prospect that systematic exercises could increase working memory
drives research at certain groups such as Torkel Klingberg at the Karolinska Institute. In 1999, Klingberg proposed computerized working memory training to achieve this for people with ADHD. In 2001, he founded a company, Cogmed, to market a WM training product. In 2002 Klingberg presented his results on 14 children with ADHD. Another Klingberg study in 2005 with 53 children with ADHD concluded "WM can be improved by training in children with ADHD". However, , a Georgia Institute of Technology
(US
) review of the world-wide literature "concluded that, as of yet, the results are inconsistent and this is likely driven by inadequate controls and ineffective measurement of the cognitive abilities of interest."
can be defined as an executive function that allows humans and animals to hold information in mind for brief periods of time. Working memory capacity differs from individual to individual and can be generally measured by the number of pieces of discrete information that a person can hold in mind at any given moment. For example, someone who can remember and repeat a series of eight instructions has a greater working memory capacity than someone who can only recall a series of five. Numerous scientific studies correlate high working memory with strength in other fundamental cognitive abilities, including attention and intelligence. Conversely, poor working memory is one of the core deficits in ADHD as well as a number of learning disabilities.
In 2001, Klingberg founded a company for working memory training, Cogmed.
Klingberg launched a double-blind placebo-controlled study, published in 2002, of 14 children to examine the effects of computerized training on a group of children with ADHD, working with two Swedish computer game developers. This population, which typically exhibits shortcomings in working memory, was chosen with the idea that any improvements in working memory would be most easily detected in daily functioning. The subjects performed training five days a week for five weeks using a video game-like program that constantly adapted its level of difficulty to the user's performance. Following the training, the students' working memory had improved substantially and ADHD symptoms were reduced. The research was later published in 2002 in the Journal of Clinical and Experimental Neuropsychology.
Klingberg and colleagues performed a larger study, published in 2005, on 53 ADHD-diagnosed children. Tests immediately following the training showed reasoning and attention span improvements in the trained group compared to the control group. Tests three months later showed that the control group had improved to the same level as the training group, so that there was no long-term effect of the training. At both the immediate and 3-month later tests, there was no difference between the control and training groups in the number of head movements (a measurement of inattention), and the number of head movements was not reduced in either group.
Following the null long-term results of the 2005 study, Klingberg's company Cogmed refined the training program and made it commercially available through licensed medical doctors and psychologists.
Other researchers from universities around the world have also studied the effects of the Cogmed company's training on children with attention issues. Among them are Notre Dame
, NYU, and the University of York
. In addition, many researchers are now exploring the use of working memory training for various new applications, with studies having been completed or launched on normal and aging adults, pediatric cancer survivors, and victims of stroke and traumatic brain injury.
In the February 2009 edition of Science, Klingberg and colleagues, led by F McNab, claimed that adaptive span
training had led to changes in dopamine
D1 and D2 receptors. In the same study, tests of "far transfer" - whether or not the skills in one test applied to very different intelligence-related skills - were made. The results were not reported. (see supporting online materials: http://www.sciencemag.org/content/suppl/2009/02/05/323.5915.800.DC1/McNab.SOM.pdf)
in the United States
reviewed the research literature on working memory training, both for children and adults affected by ADHD or another disorder and for healthy subjects. They "concluded that, as of yet, the results are inconsistent and this is likely driven by inadequate controls and ineffective measurement of the cognitive abilities of interest."
In September 2010, a study on memory training and strategy use in older adults, performed by Alden L. Gross and George W. Rebok attempted to use various learning tasks to attempt to enhance the episodic memory of older adults. The results from this experiment "suggested that younger, female, white, healthier, and more educated participants show higher strategy clustering scores initially but no characteristics were consistently associated with different trajectories in strategy clustering across all strategy clustering measures together." Furthermore, the experiment also was able to conclude successfully that "older adults can be trained to use cognitive strategies, the effects are durable, and strategies are associated with memory and everyday functioning."
Working memory
Working memory has been defined as the system which actively holds information in the mind to do verbal and nonverbal tasks such as reasoning and comprehension, and to make it available for further information processing...
, a core cognitive ability. The prospect that systematic exercises could increase working memory
Working memory
Working memory has been defined as the system which actively holds information in the mind to do verbal and nonverbal tasks such as reasoning and comprehension, and to make it available for further information processing...
drives research at certain groups such as Torkel Klingberg at the Karolinska Institute. In 1999, Klingberg proposed computerized working memory training to achieve this for people with ADHD. In 2001, he founded a company, Cogmed, to market a WM training product. In 2002 Klingberg presented his results on 14 children with ADHD. Another Klingberg study in 2005 with 53 children with ADHD concluded "WM can be improved by training in children with ADHD". However, , a Georgia Institute of Technology
Georgia Institute of Technology
The Georgia Institute of Technology is a public research university in Atlanta, Georgia, in the United States...
(US
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
) review of the world-wide literature "concluded that, as of yet, the results are inconsistent and this is likely driven by inadequate controls and ineffective measurement of the cognitive abilities of interest."
What is working memory?
Important for daily functioning, working memoryWorking memory
Working memory has been defined as the system which actively holds information in the mind to do verbal and nonverbal tasks such as reasoning and comprehension, and to make it available for further information processing...
can be defined as an executive function that allows humans and animals to hold information in mind for brief periods of time. Working memory capacity differs from individual to individual and can be generally measured by the number of pieces of discrete information that a person can hold in mind at any given moment. For example, someone who can remember and repeat a series of eight instructions has a greater working memory capacity than someone who can only recall a series of five. Numerous scientific studies correlate high working memory with strength in other fundamental cognitive abilities, including attention and intelligence. Conversely, poor working memory is one of the core deficits in ADHD as well as a number of learning disabilities.
History
In the 1970s, as the concept of working memory was becoming more widely accepted and its importance better understood, there were attempts to improve it through various methods. In one case, a college student practiced repeating numbers that were read to him aloud for an hour each day. He did this three to five times a week for twenty months until he could repeat as many as 79 digits. It would seem his working memory had improved. But in fact the same student, when asked to repeat letters, could only recall six at a time. As it turns out, the student had devised ways to group numbers and relate them to similar figures already in his long term memory. In reality, his working memory capacity had not increased. This study and others like it contributed to the prevailing assumption in the scientific community that working memory is a set characteristic unable to be improved.Klingberg et al.
"In 1999, Dr. Torkel Klingberg, then a post-doctoral [researcher] at the Karolinska Institute in Stockholm," Sweden, claimed that working memory capacity could be improved through systematic, computerized exercises. Aware of previous failed attempts to improve working memory, Klingberg's research was inspired by numerous studies demonstrating the plasticity of the human mind.In 2001, Klingberg founded a company for working memory training, Cogmed.
Klingberg launched a double-blind placebo-controlled study, published in 2002, of 14 children to examine the effects of computerized training on a group of children with ADHD, working with two Swedish computer game developers. This population, which typically exhibits shortcomings in working memory, was chosen with the idea that any improvements in working memory would be most easily detected in daily functioning. The subjects performed training five days a week for five weeks using a video game-like program that constantly adapted its level of difficulty to the user's performance. Following the training, the students' working memory had improved substantially and ADHD symptoms were reduced. The research was later published in 2002 in the Journal of Clinical and Experimental Neuropsychology.
Klingberg and colleagues performed a larger study, published in 2005, on 53 ADHD-diagnosed children. Tests immediately following the training showed reasoning and attention span improvements in the trained group compared to the control group. Tests three months later showed that the control group had improved to the same level as the training group, so that there was no long-term effect of the training. At both the immediate and 3-month later tests, there was no difference between the control and training groups in the number of head movements (a measurement of inattention), and the number of head movements was not reduced in either group.
Following the null long-term results of the 2005 study, Klingberg's company Cogmed refined the training program and made it commercially available through licensed medical doctors and psychologists.
Other researchers from universities around the world have also studied the effects of the Cogmed company's training on children with attention issues. Among them are Notre Dame
University of Notre Dame
The University of Notre Dame du Lac is a Catholic research university located in Notre Dame, an unincorporated community north of the city of South Bend, in St. Joseph County, Indiana, United States...
, NYU, and the University of York
University of York
The University of York , is an academic institution located in the city of York, England. Established in 1963, the campus university has expanded to more than thirty departments and centres, covering a wide range of subjects...
. In addition, many researchers are now exploring the use of working memory training for various new applications, with studies having been completed or launched on normal and aging adults, pediatric cancer survivors, and victims of stroke and traumatic brain injury.
In the February 2009 edition of Science, Klingberg and colleagues, led by F McNab, claimed that adaptive span
Memory span
In psychology and neuroscience, memory span is the longest list of items that a person can repeat back in correct order immediately after presentation on 50% of all trials. Items may include words, numbers, or letters. The task is known as digit span when numbers are used. Memory span is a common...
training had led to changes in dopamine
Dopamine
Dopamine is a catecholamine neurotransmitter present in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this substituted phenethylamine functions as a neurotransmitter, activating the five known types of dopamine receptors—D1, D2, D3, D4, and D5—and their...
D1 and D2 receptors. In the same study, tests of "far transfer" - whether or not the skills in one test applied to very different intelligence-related skills - were made. The results were not reported. (see supporting online materials: http://www.sciencemag.org/content/suppl/2009/02/05/323.5915.800.DC1/McNab.SOM.pdf)
Methodological issues
In 2010, Shipstead and colleagues of Georgia Institute of TechnologyGeorgia Institute of Technology
The Georgia Institute of Technology is a public research university in Atlanta, Georgia, in the United States...
in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
reviewed the research literature on working memory training, both for children and adults affected by ADHD or another disorder and for healthy subjects. They "concluded that, as of yet, the results are inconsistent and this is likely driven by inadequate controls and ineffective measurement of the cognitive abilities of interest."
In September 2010, a study on memory training and strategy use in older adults, performed by Alden L. Gross and George W. Rebok attempted to use various learning tasks to attempt to enhance the episodic memory of older adults. The results from this experiment "suggested that younger, female, white, healthier, and more educated participants show higher strategy clustering scores initially but no characteristics were consistently associated with different trajectories in strategy clustering across all strategy clustering measures together." Furthermore, the experiment also was able to conclude successfully that "older adults can be trained to use cognitive strategies, the effects are durable, and strategies are associated with memory and everyday functioning."