But I wonder if they are looking at this wrong. Novel and new tasks build brain reserve so insults like stroke and dementia are not as severe. 2 years old so I wonder if consensus has changed.
October 20, 2014
As the baby boomers enter their golden years with mounting concerns
about the potential loss of cognitive abilities, markets are responding
with products promising to allay anxieties about potential decline.
Computer-based cognitive-training software –popularly known as brain
games– claim a growing share of the marketplace. The promotion of these
products reassures and entices a worried public.
Consumers are told that playing brain games will make them smarter,
more alert, and able to learn faster and better. In other words, the
promise is that if you adhere to a prescribed regimen of cognitive
exercise, you will reduce cognitive slowing and forgetfulness, and will
fundamentally improve your mind and brain.
It is customary for advertising to highlight the benefits and
overstate potential advantages of their products. In the brain-game
market, advertisements also reassure consumers that claims and promises
are based on solid scientific evidence, as the games are “designed by
neuroscientists” at top universities and research
centers. Some companies present lists of credentialed scientific
consultants and keep registries of scientific studies pertinent to
cognitive training. Often, however, the cited research is only
tangentially related to the scientific claims of the company, and to the
games they sell. In addition, even published peer-reviewed studies
merit critical evaluation. A prudent approach calls for integrating
findings over a body of research rather than relying on single studies
that often include only a small number of participants.
The Stanford Center on Longevity and the Berlin Max Planck Institute
for Human Development gathered many of the world’s leading cognitive
psychologists and neuroscientists –people who have dedicated their
careers to studying the aging mind and brain– to share their views about
brain games and offer a consensus report to the public. What do expert
scientists think about these claims and promises? Do they have specific
recommendations for effective ways to boost cognition in healthy, older
adults? Are there merits to the claimed benefits of the brain games and
if so, do older adults benefit from brain-game learning in the same ways
younger people do? How large are the gains associated with
computer-based cognitive exercises? Are the gains restricted to specific
skills or does general cognitive aptitude improve? How does playing
games compare with other proposed means of mitigating age-related
declines, such as physical activity and exercise, meditation, or social
engagement?
The search for effective means of mitigating or postponing
age-related cognitive declines has taught most of us to recognize the
enormous complexity of the subject matter. Like many challenging
scientific topics, this is a devil of many details. The consensus of the
group is that claims promoting brain games are frequently exaggerated
and at times misleading. Cognitive training produces statistically
significant improvement in practiced skills that sometimes extends to
improvement on other cognitive tasks administered in the lab. In some
studies, such gains endure, while other reports document dissipation
over time. In commercial promotion, these small, narrow, and fleeting
advances are often billed as general and lasting improvements of mind
and brain. The aggressive advertising entices consumers to spend money
on products and to take up new behaviors, such as gaming, based on these
exaggerated claims. As frequently happens, initial findings, based on
small samples, generate understandable excitement by suggesting that
some brain games may enhance specific aspects of behavior and even alter
related brain structures and functions. However, as the findings
accumulate, compelling evidence of general and enduring positive effects
on the way people’s minds and brains age has remained elusive.
These
conclusions do not mean that the brain does not remain malleable, even
in old age. Any mentally effortful new experience, such as learning a
language, acquiring a motor skill, navigating in a new environment, and,
yes, playing commercially available computer games, will produce
changes in those neural systems that support acquisition of the new
skill. For example, there may be an increase in the number of synapses,
the number of neurons and supporting cells, or a strengthening of the
connections among them. This type of brain plasticity is possible
throughout the life span, though younger brains seem to have an
advantage over the older ones. It would be appropriate to conclude from
such work that the potential to learn new skills remains intact
throughout the life span. However at this point it is not appropriate to
conclude that training-induced changes go significantly beyond the
learned skills, that they affect broad abilities with real-world
relevance, or that they generally promote “brain health”.
As we take a closer look at the evidence on brain games, one issue
needs to be kept in mind: It is not sufficient to test the hypothesis of
training-induced benefits against the assumption that training brings
no performance increases at all. Rather, we need to establish that
observed benefits are not easily and more parsimoniously explained by
factors that are long known to benefit performance, such as the
acquisition of new strategies or changes in motivation. It is well
established, for example, that improvements on a particular memory task
often result from subtle changes in
strategy thatreflect
improvement in managing the demands of that particular task. Such
improvement is rewarding for players (the fun factor) but does not imply
a general improvement in memory. In fact, the notion that performance
on a single task cannot stand in for an entire ability is a cornerstone
of scientific psychology. Claims about brain games often ignore this
tenet. In psychology, it is good scientific practice to combine
information provided by many tasks to generate an overall index
representing a given
ability. According to the American
Psychological Association, newly developed psychological tests must meet
specific psychometric standards, including reliability and validity.
The same standards should be extended into the brain game industry, but
this is not the state of affairs today.
To date, there is little evidence that playing brain games improves
underlying broad cognitive abilities, or that it enables one to better
navigate a complex realm of everyday life. Some intriguing isolated
reports do inspire additional research, however. For instance, some
studies suggest that both non-computerized reasoning and computerized
speed-of-processing training are associated with improved driving in
older adults and a reduction in the number of accidents. Another study
revealed, for a sample of younger adults, that 100 days of practicing 12
different computerized cognitive tasks resulted in small general
improvements in the cognitive abilities of reasoning and episodic
memory, some of which were maintained over a period of two years. In
other studies, older adults have reported that they felt better about
everyday functioning after cognitive training, but no objective measures
supported that impression. Additional systematic research is needed to
replicate, clarify, consolidate, and expand such results. To be fully
credible, an empirical test of the usefulness of brain games needs to
address the following questions. Does the improvement encompass a broad
array of tasks that constitute a particular
ability, or does it
just reflect the acquisition of specific skills? Do the gains persist
for a reasonable amount of time? Are the positive changes noticed in
real life indices of cognitive health? What role do motivation and
expectations play in bringing about improvements in cognition when they
are observed?
In
a balanced evaluation of brain games, we also need to keep in mind
opportunity costs. Time spent playing the games is time not spent
reading, socializing, gardening, exercising, or engaging in many other
activities that may benefit cognitive and physical health of older
adults. Given that the effects of playing the games tend to be
task-specific, it may be advisable to train an activity that by itself
comes with benefits for everyday life. Another drawback of publicizing
computer games as a fix to deteriorating cognitive performance is that
it diverts attention and resources from prevention efforts. The promise
of a magic bullet detracts from the message that cognitive vigor in old
age, to the extent that it can be influenced by the lives we live,
reflects the long-term effects of a healthy and active lifestyle.
We also must keep in mind that studies reporting positive effects of
brain games on cognition are more likely to be published than studies
with null results –the so-called “file drawer effect”– such that even
the available evidence is likely to draw an overly positive picture of
the true state of affairs. Statistical methods such meta-analysis, which
integrates the results of many studies in a given field of inquiry,
allow estimation of effect magnitude as well as the likelihood of the
file-drawer effect. While some meta-analyses report small positive
effects of training on cognition, others note substantial disparities in
methodological rigor among the studies that cast doubt on any firm
conclusion. Further, the problems that haunt individual studies do not
simply disappear when results from such studies are summarized in a
meta-analysis. In particular, the practice of assessing specific tests
rather than broader assays of ability is just as problematic on the
level of meta-analytic integration as it is on the level of individual
studies.
In summary, research on aging has shown that the human mind is
malleable throughout life span. In developed countries around the world,
later-born cohorts live longer and reach old age with higher levels of
cognitive functioning than those who were born in earlier times. When
researchers follow people across their adult lives, they find that those
who live cognitively active, socially connected lives and maintain
healthy lifestyles are less likely to suffer debilitating illness and
early cognitive decline in their golden years than their sedentary,
cognitively and socially disengaged counterparts. The goal of research
on the effectiveness of computer-based cognitive exercise is to provide
experimental evidence to support or qualify these observations. Some of
the initial results are promising and make further research highly
desirable. However, at present, these findings do not provide a sound
basis for the claims made by commercial companies selling brain games.
Many scientists cringe at exuberant advertisements claiming improvements
in the speed and efficiency of cognitive processing and dramatic gains
in “intelligence”, in particular when these appear in otherwise trusted
news sources. In the judgment of the signatories below, exaggerated and
misleading claims exploit the anxiety of adults facing old age for
commercial purposes. Perhaps the most pernicious claim, devoid of any
scientifically credible evidence, is that brain games prevent or reverse
Alzheimer’s disease.
In closing, we offer five recommendations. Some of these
recommendations reflect experimental findings in human populations,
whereas others are based on a synthesis of correlational evidence in
humans and mechanistic knowledge about risks and protective factors.
- Much more research needs to be done before we understand whether and
what types of challenges and engagements benefit cognitive functioning
in everyday life. In the absence of clear evidence, the recommendation
of the group, based largely on correlational findings, is that
individuals lead physically active, intellectually challenging, and
socially engaged lives, in ways that work for them. Before investing
time and money on brain games, consider what economists call opportunity
costs: If an hour spent doing solo software drills is an hour not spent
hiking, learning Italian, making a new recipe, or playing with your
grandchildren, it may not be worth it. But if it replaces time spent in a
sedentary state, like watching television, the choice may make more
sense for you.
- Physical exercise is a moderately effective way to improve general
health, including brain fitness. Scientists have found that regular
aerobic exercise increases blood flow to the brain, and helps to support
formation of new neural and vascular connections. Physical exercise has
been shown to improve attention, reasoning, and components of memory.
All said, one can expect small but noticeable gains in cognitive
performance, or attenuation of loss, from taking up aerobic exercise
training.
- A single study, conducted by researchers with financial interests in
the product, or one quote from a scientist advocating the product, is
not enough to assume that a game has been rigorously examined. Findings
need to be replicated at multiple sites, based on studies conducted by
independent researchers who are funded by independent sources. Moreover,
participants of training programs should show evidence of significant
advantage over a comparison group that does not receive the treatment
but is otherwise treated exactly the same as the trained group.
- No studies have demonstrated that playing brain games cures or prevents Alzheimer’s disease or other forms of dementia.
- Do not expect that cognitively challenging activities will work like
one-shot treatments or vaccines; there is little evidence that you can
do something once (or even for a concentrated period) and be inoculated
against the effects of aging in an enduring way. In all likelihood,
gains won’t last long after you stop the challenge.
In summary: We object to the claim that brain games offer
consumers a scientifically grounded avenue to reduce or reverse
cognitive decline when there is no compelling scientific evidence to
date that they do. The promise of a magic bullet detracts from the best
evidence to date, which is that cognitive health in old age reflects the
long-term effects of healthy, engaged lifestyles. In the judgment of
the signatories, exaggerated and misleading claims exploit the anxiety
of older adults about impending cognitive decline. We encourage
continued careful research and validation in this field.
