Getting smarter
Brain-training games won’t boost your IQ, but a host of strategies can improve your cognitive abilities one piece at a time
Is it just me, or is
everybody out there looking for a quick fix?
There is something highly
compelling about the idea that there is a secret switch we can flip to
become suddenly smarter, to reveal cognitive abilities hidden inside
each of us. It is a notion that certainly has commercial appeal. Over
just seven years, the games-maker Lumosity rocketed from zero to 50
million users, promising rapid improvements in general intelligence by
playing brain-training video games for just a few weeks. (Lumosity
recently settled with the United States Federal Trade Commission for
making unsupported claims that its product was scientifically
validated.) ‘Memory health’ nutritional supplements have sales of more
than $1.5 billion, and ‘smart drugs’ – pills to enhance cognitive
performance – have become prevalent on college campuses. Purveyors of
products based on subliminal messages promise to teach us foreign
languages and cure our addictions while we sleep. And makers of headgear
that attaches electrodes to our scalps promise to rev up our brains to
improve gaming performance and other cognitive activities.
These
are global trends but, living in the US, it seems to me that there is
something particularly American to them. We have a long tradition of
positivism, progressivism and self-improvement. Some of this is great.
Thomas Edison was convinced that human existence could be dramatically
improved with rapid technological innovation, and it is hard to dispute
the transformative value of electric light and recorded sound. Henry
Wallace looked at the variable and unpredictable yields of Iowa corn
farmers and was convinced that scientific breeding and hybridisation
could do better than allowing judges to select the most attractive ears
at corn shows. His hybrid corn transformed grain farming and launched
him on a political career that landed him as Franklin D Roosevelt’s vice
president. (However, Wallace’s self-improvement enthusiasm also
extended to investigations of psychical communication with the dead,
which probably contributed to his getting booted off Roosevelt’s third
re-election campaign in favour of Harry S Truman.)
Some
of this progressive self-improvement tradition is essential, and some
is charming in a kooky way. But part of the drive to engineer a quick
fix for what ails us is alarming and dangerous. Americans have endured
generations of rapid weight-loss schemes that don’t work and are often
dangerous to health – especially diet pills from amphetamines to
fen-phen.
As the
pace of life continues to accelerate, there is increasing pressure for a
quick fix to boost our cognitive capacities – for study, for work and
for recreation. So, is there anything out there that works?
Sadly,
most of the rapid cognitive enhancers currently being peddled are not
very effective. Let’s start with brain training. None of the commercial
brain-training software being marketed is backed up by strong scientific
evidence. Lumosity started off claiming that its product was supported
by scientific research, but a number of us in the cognitive neuroscience
field were struck that the research section of the company’s website
didn’t seem to have any peer-reviewed studies demonstrating this claim.
Making such a claim without evidence is what got the company sued.
Lumosity,
Posit Science and other brain-training companies differ in many of
their particulars but share some common features. First, they ‘gamify’
training, so that it is more appealing. Second, they are adaptive, which
means that, as you get better, the game gets harder. Both of these are
solid principles of cognitive training. Third, many (but not all) of
these systems focus on training an ability called working memory, which
is the skill to keep multiple bits of information ready to hand, and
juggle some of them while using others.
Working
memory is an attractive target for cognitive training because measures
of its capacity – how many bits of information you can juggle –
correlate strongly with measures of problem-solving and reasoning, and
because working-memory tasks are easy to program into games. Some
systems also train attentional control, which is the ability to pick out
task-relevant information from among distracting information. Like
working memory, training attentional control makes theoretical sense and
can be incorporated into interactive games. So, the thinking behind
these interventions is totally reasonable.
The
problem is that experiments to test the types of techniques used by
commercial products to boost working memory and attention have not
yielded significant results. The most directly relevant was a large
study carried out by researchers at the British Medical Research
Council’s Cognition and Brain Sciences Unit in Cambridge. They recruited
11,430 participants through a TV show called Bang Goes the Theory.
One-third of them were randomly assigned to practise a broad set of
tasks focusing on memory and attention, similar to those trained by the
commercial products. One task required participants to quickly click on
symbols appearing on the screen, but only if they matched a set of
target symbols. Another task had them watching pieces of luggage going
through an airport X‑ray machine. From time to time, the conveyor belt
would stop and the participants had to report how many bags were on the
machine.
people got better at the tasks they practised but this did not transfer at all to other measures of cognition
Another
third of the participants were trained on a set of reasoning and
planning tasks: one of these required them to find which shape did not
belong in a set, another required them to slide tiles around on a grid
to place them in numerical order. The remaining third were assigned to a
control group and received no training. Everyone completed a separate
set of IQ-like benchmarking tests before and after the training period
to measure a range of cognitive abilities. For example, in one test
people had to verify whether a rule (eg ‘the circle is not smaller than
the square’) applied to a picture, and in another they had to repeat
back increasingly long strings of digits. Both of the training groups
improved dramatically on the tasks they practised – but showed no more
gain on the benchmarking tests than the control group.
Another
large experiment in the US called the ACTIVE study (for Advanced
Cognitive Training for Independent and Vital Elderly) aimed to figure
out what might stave off the cognitive decline associated with ageing.
In this study, the researchers recruited 2,832 people and randomly
assigned them to practice tasks of memory, reasoning or cognitive speed,
or to a control group that received no special training. Again, people
got better at the tasks they practised but this did not transfer at all
to other measures of cognition.
For
instance, people in the memory group were taught strategies for
memorising world lists. Sure enough, they got better at memorising
words, but not at reasoning out the patterns in series of numbers or
travel schedules. Conversely, people in the reasoning group were taught
strategies for finding patterns, and they got better at that task but
did not improve at memorising words. (On a follow-up test with a
five-year delay, there was a hint of an effect that those participants
who were in the reasoning training group were helped somewhat with
everyday tasks, so perhaps all hope is not lost. But this is definitely
not the magnitude of effect that one would expect to be meaningful in
boosting intelligence, and it was not apparent in the short-term
follow-up.)
Cognitive-enhancing
drugs actually have a bit more evidentiary support than brain-training.
It has been known for a while that caffeine and nicotine allow people
to respond faster, stay more vigilant and score higher on some kinds of
standardised tests. Prescription stimulants such as Adderall
(amphetamine) and Ritalin (methylphenidate), which have been shown to be
effective in treating attention-deficit disorder, also improve
cognitive function in healthy people. These effects are not huge, and
they are not always consistent, but they are real.
What
is less well-known is the trade-off. All of these drugs have pretty
short half-lives. What happens when you come down? An ideal cognitive
supplement would boost performance and then return you to your baseline.
However, a likely possibility is that stimulant drugs produce a rebound
effect, reducing cognitive function once they wear off. This might
still be an acceptable trade-off: if you know when you have to be ‘on’,
it might be perfectly fine to be a little duller for a while afterwards.
This trade-off is particularly acute for habit-forming stimulants such
as nicotine. If you don’t have much control over when you use the drug,
then you have less ability to time its effects to be helpful.
More
concerning to me is the use of stimulants in developing brains. One of
the important things we have learned about brain development over the
past 40 years is that the brain undergoes more protracted maturation
than any other body system. The prefrontal cortex is the slowest part of
the brain to mature, undergoing substantial change well into the 20s.
And the prefrontal cortex is absolutely critical for higher brain
function – for organising behaviour in extended tasks, for exercising
self-control, and for planning actions in the future. The effects of
cognitive-enhancing drugs on brain development is still imperfectly
understood, but for all these drugs there is a real risk that abuse can
harm long-term brain development.
Subliminal
training programs claim to change your brain by inserting information
without your awareness. For example, many of these products claim to
have a verbal message recorded at a very low level along with a much
louder recording of nature sounds or relaxing music. The idea is that
words presented too quietly to be consciously detected are able to sneak
past some cognitive defences and reprogram the brain. Better yet,
purveyors of subliminal training systems claim that because you don’t
need to be aware of the training messages, they work even while you’re
sleeping.
Suppose
you want to kick cigarettes or lose weight. Wouldn’t it be great if you
could just drive around with a tape that played soothing music or
sounds with subliminal messages buried in them that could change your
behaviour? Or suppose you wanted to learn Portuguese for that trip to
Brazil? Why spend hundreds of hours drilling vocabulary and grammar if
you can play the language while you sleep and learn it? The trouble is
that this idea makes no sense in terms of what we know about the mind
and brain, and there is very good evidence that it simply doesn’t work.
People who listen to weight-loss tapes lose no more weight than those
who listen to tapes with no messages or no tapes at all, and people who
try to learn words in their sleep don’t learn.
Electrical stimulation
– at the right dosage with the right technique in the right location –
can produce modest enhancement of some kinds of learning and motor
function
What
about electrical stimulation? It’s certainly the most sci-fi cognitive
enhancer out there. Electrical stimulation of the brain has actually
been around for a long time. In the 19th century, physiologists began
studying the nervous system in non-human animals by inserting electrodes
directly into the brain. This technique was picked up by neurosurgeons,
and forms an important component of surgical planning for brain surgery
to this day. But direct stimulation of the brain is highly invasive and
therefore rare. More practical for human use are techniques that use
external stimulators to induce electrical changes in the brain.
The
one that has received the most attention for cognitive enhancement is
called transcranial direct current stimulation (tDCS). It works by
applying a mild electrical current to electrodes placed on the scalp.
But tDCS does not directly cause particular neurons to fire; it shifts
the electrical potential in a part of the brain, which makes it more or
less likely that neurons there will fire when stimulated. Scientific
attention to tDCS has been building over the past 20 years – and has
been picked up by hobbyists and entrepreneurs. DIY tDCS explorers have
been building their own electrical stimulators, and at least one company
has commercialised a tDCS product aimed at gamers.
Do not try this at home. Really.
As
it is used in the lab and in the clinic, tDCS is very safe – a recent
review of data from 3,836 subjects found that adverse effects are mainly
sensations of itching, tingling and the like, with a smaller number of
people experiencing headaches. My lab at Washington University in St
Louis has started working with the technique and I have been a subject; I
find it easy to work with and totally innocuous to experience, and I
encourage people to participate in tDCS research if they have the
chance. (My guess is that the headaches are mostly due to the headband
needed to hold the electrodes in place; headaches occur as often in
controls as in people undergoing stimulation.)
However,
to make tDCS safe requires equipment with proper safety controls, and
some basic knowledge about neuroanatomy and physiology. Unfortunately,
enthusiasts in the DIY tDCS have suffered burns and headaches from
stimulation gone wrong. Worse yet, there is a real risk that applying
electrical stimulation improperly could cause permanent injury. There
are intriguing findings that tDCS – applied at the right dosage with the
right technique in the right location – can produce modest enhancement
of some kinds of learning and motor function.
For
example, in one study Lauren Richmond, now a postdoctoral fellow in my
laboratory, and colleagues trained people to hold increasingly long
sequences of letters or spatial locations in mind. During training, half
of the participants received tDCS over their left prefrontal cortex, a
part of the brain known to be important for this kind of memory. The
other participants were wired up during training, but the stimulator was
set to shut itself off so that they received a trivial dose of current.
Everyone improved on the tasks over a fortnight with 10 training
sessions, but those who got the stimulation improved faster. However, at
this point the effects are too small and variable to come anywhere
close to counterbalancing the risks of trying this on yourself outside
of a reputable clinic or lab. Also, we don’t yet know if a tDCS-induced
gain in one cognitive ability comes at a cost to some other ability.
So,
does all this mean that there is no hope for cognitive enhancement? My
view is that there is actually lots of hope, as long as we are not
unrealistic about what we can achieve. Right now, I think the best bet
is cognitive training – but not the kind we’re being sold. Firms such as
Lumosity, Posit Science and Jungle Memory are trying to do something
that learning scientists call ‘far transfer’ – training on one task, and
transferring that gain to a very different task.
For
example, suppose I want to get better at keeping track of baseball
statistics or learning the names of new acquaintances. The far transfer
approach goes like this: I sign up for a brain-training program, boost
my working memory capacity and attentional control, and this improves my
ability to track stats or remember new people. The big advantage of
this approach is that, if successful, it gives broad benefits. If I
really could increase my general cognitive ability, it would help me out
in many facets of my life. The trouble is that far transfer is really hard to come by. That is what is shown by the data I described before.
What is the alternative?
Scale down your expectations and aim for near transfer.
If you want to get good at baseball scorekeeping, practise that. If you
meet lots of people and need to learn their names, practise that. For
both scorekeeping and name-learning – and many other cognitive tasks –
there are well-known techniques that have been shown to be effective.
For
example, there are two techniques that are very helpful for learning
new associations between faces and names. First, practise the
association before you lose it. When you meet someone, repeat his name
to yourself and use it in conversation if possible. After an encounter,
review the people you met and rehearse their names. Second, come up with
a meaningful association with the name. It can be silly – silly actual
works better. For example, if you are out for pizza and meet a new guy
named Pete, let his virtual nickname be ‘pizza Pete’. This totally
works. I teach a class of two to three dozen students each fall, and I
try to learn everyone’s name before the first day. This doesn’t come
naturally to me, so I print out the roster with their pictures and
practise a bunch of times naming each picture, rehearsing my virtual
nicknames each time.
For
training to be effective, you have to stick with it, and it is much
easier to do so if the training is fun, and if it embeds regular rewards
along the way
For
memorising numbers such as baseball statistics, the rise of memory
competitions has pushed dramatic improvements in training techniques.
The British memory champ Ben Pridmore is a great example. He was the
first person to successfully memorise a deck of cards in under 30
seconds, and has won all kinds of championships. One competitive event
requires that you spend 15 minutes listening to a string of digits and
then write them all down. In 2008, Pridmore managed 153. (The current
record, held by Lance Tschirhart of the United States, is 456.)
Pridmore wrote How to Be Clever
(2011), which lays out exactly the techniques and practice regimens he
adopted to achieve this performance. The achievements of such memory
athletes show how powerful near transfer can be. But getting good at one
of these tasks does not make you smart in general. Pridmore tells the
reader this right on page three: ‘Intelligence I can’t do anything
about.’
There is
one piece of advice, however, that the brain-training products have
exactly right: gamification. For training to be effective, you have to
stick with it, and it is much easier to do so if the training is fun,
and if it embeds regular rewards along the way. Psychology and
neuroscience are learning a lot about how to design training systems
that people want to use, and that produce efficient results.
Does
this mean that nothing can make us smarter in general? Not at all. Far
transfer in training, or safe and effective smart drugs or brain
stimulation, could be right around the corner. None of these are things
that shouldn’t work in principle. (I wouldn’t bet on subliminal messages
working out, though.) It could be that one of these technologies – or a
new one – will break through and really make us smarter. In fact, in
the past century our species experienced a massive increase in smarts
that happened very fast in evolutionary terms – too fast to have been
due to genetic changes. In 1984, the psychologist James Flynn was
studying intelligence testing; he reported that, from 1932 to 1978, IQ
scores in the US had increased 13.8 points. Around the world, he found
increases ranging from five to 25 points.
These are massive increases. Take the US number as a reasonable overall estimate. An increase of 13.8 percentage points means
that a score which would have placed you squarely in the middle of the
distribution in 1932 would now land you below the 20th percentile, with
more than 80 per cent of people scoring better than you. Nobody knows
exactly what drove these increases, but a good guess is that it was
largely due to basic improvements in nutrition and education, which
allowed brains to better develop to their full capacity.
If
you are reading this, you probably benefited from the nutritional and
educational improvements of the 20th century, so you’ve already got your
brain boost. But there is still something you can do to improve and
maintain general cognitive ability: get some exercise. Specifically,
cardiovascular exercise such as walking, running, biking or swimming.
Improving cardiovascular fitness has been shown causally to improve
cognitive function, and this has been traced to the growth of new
neurons in the brain and to improvements in the function of existing
neurons.
we’re already smarter than our grandparents. And if we live an active lifestyle, we can get smarter and stay smart throughout our lives
For
example, in one study older adults were asked to make quick visual
judgments about alphanumeric characters while avoiding being distracted
by nearby characters. Then, half of them were assigned to improve their
cardiovascular fitness by taking increasingly intensive walks, maxing
out at 40-45 minutes of brisk walking. The other half were assigned to
do stretching and toning exercises. After training, the initial task was
repeated. The group who walked improved at avoiding being distracted by
the extraneous, and showed changes in brain activity while doing the
task. The stretching and toning group did not change. A particular focus
of this research has been on ageing. The results suggest that exercise
can help older adults maintain and improve cognitive function. Given
that exercise has lots of other benefits, what’s not to like?
Now,
neither good rearing nor cardiovascular fitness is a quick fix that
will make us cognitive superheroes. But I think the story is mostly good
news. First, if there is something you really need to get good at,
chances are that there is a training technique that will be effective.
Second, we’re already smarter than our grandparents (on average). And
finally, if we live an active lifestyle, we can get smarter and stay
smart throughout our lives.
Sometimes,
the function of science is to overturn common sense, achieving a deeper
understanding of nature. Other times, common sense turns out to be
right. When it comes to getting smarter, common sense turns out to be on
target so far. Six-week mental workouts, smart drugs, learning while
you sleep and zapping yourself into genius all sound a little too good
to be true – and for now they are. But we can all think better in
specific domains if we engage in focused practice, and be smarter,
happier and healthier if we take care of ourselves.
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Some will learn - others will continue on their same path!
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