The growing field of cognitive training (one of the tools for brain fitness) can appear very confusing as the media keeps reporting contradictory claims. These claims are often based on press releases, without a deeper evaluation of the scientific evidence.
Let’s take a couple of recent examples, in successive days:
“It doesn’t work!” type of headline:
Reuters (Feb. 10, 2009) Formal brain exercise won’t help healthy seniors: research”
Healthy older people shouldn’t bother spending money on computer games and websites promising to ward off mental decline, the author of a review of scientific evidence for the benefits of these “brain exercise” programs says.
It works! type of headline:
ScienceDaily (Feb. 11, 2009) “Computer Exercises Improve Memory And Attention, Study Suggests”
According to the researchers, participants who used the Brain Fitness Program also scored as well as those ten years younger, on average, on memory and attention tests for which they did not train.
So, does structured brain exercise / cognitive training work or not?
The problem may in fact reside in asking this very question in the first place, as Alvaro pointed out a while ago in his article Alzheimer’s Disease: too serious to play with headlines.
We need a more nuanced set of questions.
1. Cognition is made of several different abilities (working memory, attention, executive functions such as decision-making, etc)
2. Available training programs do not all train the same abilities
3. Users of training programs do not all have the same needs or goals
4. We need to differentiate between enhancing cognitive functions and delaying the onset of cognitive deficits such as Alzheimer’s.
Let’s illustrate these points, by analyzing briefly the very same study that allowed Reuters Health to claim that “Formal “brain exercise” won’t help healthy seniors”:
1 + 2: Contrary to what you may believe if you only read the Reuters headline, the review study cited did find 10 high-quality studies in which brain exercises successfully improved targeted functions in healthy older adults. Which suggests that brain exercises “work” when used to boost specific cognitive skills, and that effects last longer than the training itself.
Training programs do not all train the same abilities. If I need to train my executive functions and use a program that trains basic auditory skills, I may well conclude that this program does not “work”. But this program may work for somebody who needs help in auditory processing areas.
3 + 4- Why a person uses a training program makes a big difference in the assessment of whether this program works or not.
As mentioned above, a person who reads the review asking whether using a training program may enhance some cognitive skills, will probably conclude that a good number of programs work — age itself is not an obstacle.
Further, the review shows that in the 4 studies that tracked benefits a few months to a few years after the training, benefits (or significant part of them) remained. So it is not that the report didn’t find any study that showed that the programs work beyond the training period itself; what it noted, and justifiably so, was the very small number of long-term studies to start with!
The authors of the review also acknowledge that evidence supports the value of cognitive training with people who have mild cognitive impairment and even Alzheimer’s Disease (before excluding such evidence from their review in order to focus exclusively on healthy adults).
Now, if someone in Obama’s healthcare team reads the review asking, Is there enough evidence to invest $5 billion today in buying products and distribute them to the public at large in order to prevent the upcoming Alzheimer’s Disease problem?, it is much harder to decide that the programs work for the good reason that scientists do not know yet whether this is an efficient and sustained way to do so. It would be arguably be premature to invest those $5 billion in buying products today.
Let’s now contrast in more depth those 2 recent studies and try to understand what they mean and what they do not mean.
Papp, Walsh, & Snyder (2009), reported in Reuters as “training doesn’t work”, conducted a meta-analysis of the studies published after 1992 that used cognitive training with healthy older adults. They included only high-quality well-conducted studies (randomized controlled trials published in peer-reviewed journals), which left 10 studies in the analysis.
The results consistently suggested that cognitive skills can be trained, no matter the age group, on a short-term basis. However it is not always the case that the training benefits transfer to untrained tasks, even when these are cognitively close to the trained tasks.
Only 4 studies assessed long-term training benefits. They showed that small benefits were maintained over time after the training (during a period of several months for 2 studies and up to 5 years for one study).
The authors concluded that there was almost no evidence for long-term benefits BECAUSE most of the studies do not assess long-term benefits.
What this study means:
- Short-term improvements can be obtained for some specific cognitive skills when using a computerized training program. These improvements last longer than the training itself.
- Studies that assess long-term benefits of cognitive training (i.e., delay in onset of dementia) are rare; thus the evidence for long-term benefits is scant. We need more research.
What this study does not mean:
- Cognitive training CAN postpone the emergence of Alzheimer’s.
- Cognitive training CANNOT postpone the emergence of Alzheimer’s.
- We simply don’t know yet! We need more research tracking the direct impact of cognitive training over the long haul.
Now, let’s review the other study, reported in Science Daily.
Smith and colleagues (2009), “training works!”, reported the results of a large randomized, controlled, double-blind study testing the short-term effects of a computerized training program (Posit Science classic program). The IMPACT study involved 487 healthy adults, aged 65 and older, for an amount of 40h of training (1h per day, 5 days per week for 8 weeks). Participants either used a brain training program or watch educational DVD followed by quizzes (control group). The program includes 6 exercises designed to improve the speed and accuracy of auditory information processing.
Participants who used the training program showed improvement in most of the tests used to assess their auditory memory performance. Such improvement was not shown in the control group.
What this study means:
- Short-term improvements can be obtained for some specific cognitive skills by using a computerized training program.
- These improvements can generalize from the trained tasks to untrained tasks that are cognitively close.
What this study does not mean:
- Computerized training programs can postpone the emergence of dementia.
- Computerized training programs cannot postpone the emergence of dementia.
- This training generalizes to every important cognitive skill one would like to maintain as we age, or that one’s brain get’s 10 years younger.
- All training programs will show benefits for everybody: Training benefits do not seem to transfer to tasks that are not cognitively close to the trained tasks. Thus one needs to understand what tool to use — which is why SharpBrains released this 10-Question Evaluation Checklist to help consumers and professionals make informed decisions.
What those 2 recent studies say and imply
- Cognitive training can help healthy adults improve specific cognitive skills, and improvements seem to last longer than the training itself (Willis et al., 2006; Smith et al., 2009).
- Cognitive training can help adults in the early stages of cognitive impairment and dementia improve some cognitive skills (Sitzer et al, 2006)
- One needs to make informed decisions. SharpBrains’ Evaluation Checklist may prove useful.
What neither study says or implies
- Whether cognitive training can postpone the emergence of dementia: More long-term studies are needed. (We know that mentally stimulating activities can help build a Cognitive Reserve and delay symptoms of Alzheimer’s Disease, but that evidence is not based on randomized clinical trials like the ones discussed above).
- Papp, Walsh, & Snyder. (2009). Immediate and delayed effects of cognitive interventions in healthy elderly: A review of current literature and future directions. Alzheimer’s & Dementia, 50–60.
- Sitzer, Twamley, & Jeste (2006). Cognitive training in Alzheimer’s Disease: A meta-analysis of the literature. Acta Psychiatr Scand, 114, 75–90.
- Smith et al. A Cognitive training program designed based on principles of brain plasticity: Results from the Improvement in Memory with Plasticity-based Adaptive Cognitive Training Study. Journal of the American Geriatrics Society, April 2009.
- Willis, S. L., Tennstedt, S. L., Marsiske, M., Ball, K., Elias, J., Koepke, K. M., Morris, J. N., Rebok, G. W. Unverzagt, F. W. Stoddard, A. M., & Wright, E. (2006). Long-term effects of cognitive training on everyday functional outcomes in older adults. Journal of the American Medical Association, 296(23), 2805–2814.
– Pascale Michelon, Ph. D., is SharpBrains’ Research Manager for Educational Projects. Dr. Michelon has a Ph.D. in Cognitive Psychology and has worked as a Research Scientist at Washington University in Saint Louis, in the Psychology Department. She conducted several research projects to understand how the brain makes use of visual information and memorizes facts. She is now an Adjunct Faculty at Washington University.