Jun 12, 2008
As noted in our Market Report, we expect the field of cognitive training (or “brain fitness”) software to grow in a variety of education and health-related areas over the next years. One of the most promising areas in our view: helping children and adults with attention deficits improve brain function to reduce ADHD symptoms.
I am glad to present this in-depth discussion on the results of two recent high-quality scientific studies. Let me start with Dr. Rabiner’s conclusion:
“Results from these two cognitive training studies highlight that cognitive training interventions may provide an important complement to traditional medication treatment and behavior therapy. Both studies included appropriate control groups, employed random assignment, and had outcome measures provided by individuals who were “blind” to which condition children were assigned to. They are thus well-designed studies from which scientifically sound conclusions can be drawn. They add to the growing research base that intensive practice and training focused of key cognitive skills can have positive effects that extend beyond the training situation itself.”
Without futher ado…enjoy the article!
Two New Cognitive Training Studies for ADHD Yield Promising Findings
— By Dr. David Rabiner
Although medication treatment is effective for many children with ADHD, there remains an important need to explore and develop interventions that can complement or even substitute for medication. This is true for a variety of reasons including:
1) Not all individuals with ADHD benefit from medication.
2) Among those who benefit, many have residual difficulties that need to be addressed via other means.
3) Some individuals experience adverse effects that prevent them from remaining on medication.
4) Medication treatment does not result in benefits that extend beyond when medication is being taken.
Except for #3 above, the same limitations hold for behavior therapy, which is the other intervention for ADHD that is widely considered to have a strong evidence base at this time.
Because of these limitations, some researchers have pursued cognitive training as an alternative method of treatment. The basic idea behind cognitive training is that important cognitive skills such as attention and working memory can – like any other skill – be strengthened and enhanced with intensive and focused practice. Furthermore, when an individual builds these skills the benefits may endure beyond the time when the actual training is provided.
Although this is a logical and compelling idea, the research base as it applies to individuals with ADHD is rather limited and the idea that attention is a skill that could be strengthened by focused training has not been carefully studied. In fact, when I was preparing a grant application several years ago for an attention training study, I was surprised to locate fewer than 5 studies of this issue. Furthermore, these were generally small preliminary studies that would be considered pilot investigations.
In recent years, however, researchers in the ADHD field have devoted greater attention to examining the potential benefits of cognitive training for ADHD. Below, I review 2 recent studies that highlight the potential value of training oriented approaches.
– Study 1: Computerized Progressive Attentional Training for Children with ADHD –
This study was conducted with 36 6-13-year-old children in Israel who were diagnosed with ADHD. Results from this study were published last year in Child Neurospsychology [Shalev, Tsal, & Mevorach (2007). Computerized progressive attentional training: Effective direct intervention for children with ADHD. Child Neuropsychology, 13, 382-388.]
Participants were randomly assigned to receive 8 weeks of computerized attention training (one hour sessions two times per week) or to a control group. The basic premise of computerized attention training is simple: the program requires children to attend to a variety of computer exercises and to make different responses depending on the stimuli presented. For example, a particularly simple task would require the child to press the space bar each time the number 2 was flashed but to refrain from responding when any other number is flashed. To perform well, the child must sustain their attention and refrain from responding impulsively.
Although other tasks may be far more complicated, and place demands on both problem solving skills and working memory, all tasks require sustained attention to do well. They also become more difficult and longer as the child moves through the training program. Thus, the child receives repeated practice in sustaining attention to increasingly challenging tasks that last for longer time periods. Ideally, the difficulty level adjusts to match the child’s ongoing performance so that the child is constantly challenged to perform at their best possible level – not too easy but not too hard.
By succeeding in the program, the child is demonstrating an increasing ability to sustain their attention to challenging cognitive activities. Although children may get better at attending to the actual computer exercises, however, the important question is whether this generalizes to the classroom and other settings where focused attention is critical for success. If not, become better at attending to the attention training exercises would be of little value.
The attention training program tested in this study was designed to train 4 different aspects of attention: sustained attention (the ability to maintain attention and persist on task until completion), selective attention (the ability to maintain a specific cognitive set in the face of competing distractions), orienting attention (directing one’s attention to critical stimuli), and executive attention (allocating attentional resources between competing demands and choosing what to attend to). During each session children were trained on these different types of attention and the tasks become more difficult as children’s performance improved.
Children in the control group played computer games – rather then receiving attention training – for the same amount of time. These games also required children to sustain their attention to succeed and became more difficult as children progressed. Thus, the amount of time children spent under adult supervision working on computer activities that became more difficult as they progressed was the same for each group. Unlike children randomly assigned to the attention training group, however, children in the video game control condition were not exposed to activities that focused on training specific components of attention.
Before and immediately following training, parents rated their child’s ADHD symptoms using a standardized behavior rating scale (the authors report that parents were blind to which group their child was in). In addition, academic performance was tested pre- and post-training using math problems, reading comprehension problems, and passage copying problems taken directly from children’s school books. Standard achievement tests were not used because such tests are not available in Hebrew. Information about whether any children were on medication during the training or during testing was not provided.
– Results –
Encouraging results were obtained. Parents of children in the attention training group reported a significant decline in their child’s inattentive symptoms compared to parents of children in the control group. The change in hyperactive-impulsive symptoms was in the same direction but was not significant.
After controlling for academic performance before training, children who received attention training did significantly better than controls in reading comprehension and in their speed of copying passages. Math performance was in the same direction but was not significant.
– Summary and Implications –
The authors conclude that their attention training program produced significant improvements in parents’ ratings of inattentive symptoms and on academic tests. This is the first demonstration I am aware of that suggests attention training may improve academic performance.
The authors note several important limitations to their study. First, the sample is relatively small. Second, no behavioral data was obtained from children’s teachers. Third, there was no extended follow-up so the duration of the benefits observed at post-test is unknown. To these concerns I would add that the academic results would be stronger if a standardized achievement measure had been used. Finally, I wonder if parents truly remained blind to whether their child was receiving attention training or was in the video game control group.
These limitations not withstanding, these are promising results that highlight the potential of attention training procedures for children with ADHD. A larger controlled trial that addresses the limitations of the current work is certainly warranted.
Note – To my knowledge, this attention training program is not currently available outside of Israel.
– Study 2: The impact of different types of working memory training for children with ADHD –
Working memory is a key cognitive function that allows individuals to hold information in mind for brief periods of time. This ability plays an important role in countless daily tasks including following directions, accurately tracking conversations, reading comprehension, solving complex math problems, and staying focused on a project. Current theories of ADHD that emphasize the critical role of executive functions highlight working memory deficits as an important aspect of the disorder; in fact, research has shown that many individuals with ADHD have poor working memory compared to same age peers without the disorder.
A study published several years ago reported evidence that working memory is a skill that can be improved with intensive training. In a randomized controlled trial conducted with 53 children diagnosed with ADHD, working memory training was found to yield significant gains in non-trained working memory tasks and a reduction in ADHD symptoms as reported by parents (you can find a review of this study Here). Additional controlled studies of working memory training have reported positive results in other groups including younger and older adults without ADHD, typically developing preschoolers, and stroke victims. Until recently, however, additional controlled studies documenting positive effects in children with ADHD have not been reported.
At the May 2008 recent meeting of the American Psychiatric Association, Dr. Christopher Lucas and his colleagues at NYU Medical School presented new data on the use of working memory training in children diagnosed with ADHD. Their study reported on the results of 2 different types of working memory training – auditory training or visual-spatial training – conducted with 46 children aged 7-12 who were participating in an intensive summer treatment program for ADHD.
Participants were randomly assigned to received either auditory or visual spatial working memory training using the computerized training program developed by Cogmed. The idea behind assigning children to these different types of training was to see whether one was more effective then the other; the researchers had hypothesized that children who received visual-spatial training would achieve better results.
A typical auditory training exercise would involve the computer presenting the child with a string of digits, and the child had to subsequently indicate the correct order – either forward or backward – via the keyboard. In a typical visual spatial working memory training task, the child would be required to recall the location of different objects that lit up on the screen. You can view actual examples of the working memory training tasks Here.
Training took place for 30-35 minutes per day, 4 days per week, over a 6-week period so that a target of 25 training days could be provided. Both auditory and visual-spatial training protocols automatically increased the difficulty level of the working memory tasks depending on how well the child is performing, becoming more difficult when the child is successful and easier when the child is struggling. These adjustments are made on nearly a trial by trial basis by increasing or decreasing the number of items to recall. As a result, the child is consistently challenged to work at their maximum performance level without the task becoming so difficult that they become frustrated and give up.
The researchers were interested in 2 basic questions. First, did children who received visual-spatial training show greater gains in working memory performance on non-trained tasks than children who received the auditory working memory training? This was assessed by having children complete a comprehensive working memory assessment before and after training using tasks that differed from what they were actually trained with. It is important to evaluate training using tasks that differ from training activities to see whether training improvements extend to non-trained activities.
The second question was whether visual-spatial working memory training was also associated with behavioral improvements. To answer this question, the researchers examined the number of positive behavior points, i.e., points awarded for behaving appropriately and following camp rules, that children in both groups received from camp counselors between weeks 4 and 6 of the training. The counselors who awarded points were not aware of which training condition children had been assigned to.
This represents a stringent test of working memory training on behavior for several reasons. First, the ratings were being made by blind observers. Second, most children were being treated with medication, and their behavior would already have improved because of this. Third, all children were involved in an intensive behavioral therapy program designed to promote positive behavior. Thus, any improvement from working memory training would be above and beyond gains achieved from treatments that were already in place.
– Results –
Before and after the training, children were tested on several non-trained measures of working memory. Consistent with the researchers’ prediction, children who received visual-spatial training performed significantly better on several of these tasks than children who received auditory working memory training.
Of particular interest is that children who received visual-spatial working memory training earned significantly more positive behavior points from the camp counselors. Thus, these children were rated as doing a better job of consistently following camp rules and behaving appropriately.
– Summary and Implications –
Results from this study support the benefits of working memory training for children with ADHD and indicate that training of visual-spatial working memory is especially important. The fact that this training was associated with an increase in positive behavior above and beyond medication and behavior treatments already in place is a very encouraging result.
As with Study 1, this study has several limitations to consider. Although the behavior improvements noted by camp counselors is important, it would also be important to document that such behavioral gains were also observed by parents and teachers. This, however, was not examined in the study. As with Study 1, there was no extended follow-up so the duration of training benefits can not be determined.
– Overall Summary –
Results from these two cognitive training studies highlight that cognitive training interventions may provide an important complement to traditional medication treatment and behavior therapy. Both studies included appropriate control groups, employed random assignment, and had outcome measures provided by individuals who were “blind” to which condition children were assigned to. They are thus well-designed studies from which scientifically sound conclusions can be drawn. They add to the growing research base that intensive practice and training focused of key cognitive skills can have positive effects that extend beyond the training situation itself.
As noted above, however, each study has limitations that should be addressed in subsequent work. It is encouraging to see the momentum for such work building and I look forward to reviewing other studies in this important area as they become available.
– Dr. David Rabiner is a child clinical psychologist and Director of Undergraduate Studies in the Department of Psychology and Neuroscience at Duke University. He publishes Attention Research Update, an online newsletter that helps parents, professionals, and educators keep up with the latest research on ADHD, and teaches the online course How to Navigate Conventional and Complementary ADHD Treatments for Healthy Brain Development.
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