27 July 2019 | New Scientist | 37
In one recent study, applying a small electrical
current over part of the frontal cortex
enhanced decision-making and impulse
control. In another, volunteers were trained to
increase their own brain activity in the ventral
tegmental area, which is involved in the release
of the motivating neurotransmitter dopamine.
In theory, this should have boosted their
motivational levels.
Neither technology is available outside of
the lab – yet. But one day taking direct action
on your flawed human brain might be possible.
Do something else
If you want to eat better, join an exercise class.
That was the conclusion of a 2015 study that
followed more than 6000 people for four
years. People who upped their exercise during
the study period increased their intake of fruit
and vegetables more than people who already
exercised regularly or who gave up their fitness
plans early on.
The explanation for this is that, since both
behaviours share the same goal, doing one
gives you a head start on the other. These
“behaviour spillovers” can affect many aspects
of our lives. Research shows that taking up
recycling at home can lead to more
environmentally friendly shopping decisions,
and giving money to charity makes it more
likely that you will do the same again.
But beware. These spillovers don’t always
have positive effects. Doing a “good” thing –
going for a run, for example, or eating a healthy
snack – can sometimes lead you to feel that you
have earned the right to do something “bad”.
No one said that outsmarting yourself was
going to be easy. ❚
the finish line. Blood pressure drops, robbing
the brain of the fuel it needs to really get stuck
in. Several studies have also linked positive
fantasies about the future to an increased
likelihood of depression months later.
Strangely, focusing on the worst-case
scenario might actually be more effective.
In one study, people who were anxious about
public speaking performed better if they were
first allowed to focus on the likelihood of
messing it up. This “defensive pessimism”
works because, unlike fantasising about
success, it gives your brain a much-needed
kick up the backside.
Train your brain
Everything you do changes your brain –
at least temporarily. Whether it is possible
to deliberately change your brain to achieve
a specific goal, however, is an open question.
Turning good intentions into restraint is
the job of the brain’s executive control system,
much of which is found in the prefrontal
cortex. This cortex works with the parietal lobe
to keep our attention on a goal for long enough
to make progress towards it, while inhibiting
our less-than-sensible impulses.
Some people believe that activity in these
networks can be boosted with training. For
example, Barbara Sahakian, a neuroscientist
at the University of Cambridge, has found that
an iPad game called Decoder, which involves
cracking numerical codes while ignoring
distractions, improved people’s ability to
stay “in the flow” and, potentially, to stick to
their goals. “I think that cognitive training is
a way for people to change and develop
improvements in cognition and behaviour,”
says Sahakian.
The million-dollar question for all types
of cognitive training, though, is whether
improvements seen in the lab translate into
lasting real-world change. So far that hasn’t
been shown. In one recent study, cognitive
training did improve volunteers’ diets for the
month after the study but didn’t translate into
lower weight after six months.
Andrew Jones, a health psychologist at the
University of Liverpool, UK, recently reviewed
the evidence that health behaviours can be
trained. “These kind of cognitive training
paradigms might demonstrate some promise
under laboratory-based conditions, [but] they
very rarely translate to sustained behaviour
change in the real world,” he says.
The good news is that in future we might
be able to work more directly on the brain’s
motivation and impulse control systems.
Caroline Williams is a
consultant for New Scientist
and author of Override
(Scribe UK)
FAT
CA
ME
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/GE
TT
Y
What we do in the face of temptation
depends on the activity in several brain
regions, some devoted to pleasure
and others that are in charge of our
long-term goals. Your chances of
staying on track depend on which
circuit is dominant at any one time.
In the pleasure corner, the
ventromedial prefrontal cortex, which
is involved in emotional decision-
making, links to the amygdala, which
processes emotions, and the striatum,
which is involved in putting rewarding
plans into action. This network,
which chugs away below the level
of consciousness, is what makes us
choose fun, chocolate and beer, or
whatever happens to feel good at any
given moment. This might not always
be the unhealthy option – if you
happen to love vegetables, exercise
and work.
If, however, your long-term goals
don’t match what feels good, another
circuit needs to cut in to help you stay
on track. The dorsolateral prefrontal
cortex is in charge of inhibition,
attention and switching behaviours,
and can override the will of the
ventromedial prefrontal cortex.
But you need to keep your eyes on
the prize. Being distracted, overloaded
or stressed is likely to take your
attention elsewhere and leave you
vulnerable to fun, but unhelpful, slips.
The brain’s decision-
making battleground
Believe in
willpower but
don’t think too
positively