Today, here's the latest--how can developing our brains help us with questions of self-control (such as, if you're on a diet, how do you turn down the big hot fudge sundae)??? Read on:
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Mmmm, a hot fudge sundae. The diet is supposed to start today, but surely it can wait until tomorrow -- or maybe the next day.
Many people know what's
good for them and choose to do the exact opposite, especially when it
comes to diet and exercise. Researchers are turning to the brain to find
out what's behind this lack of self-control, a topic discussed in
length at the American Association for the Advancement of Science
meeting in Boston earlier this year.
In the future, there may
be brain-based solutions to help you avoid that sundae; for now,
researchers say, we can shape our environments to help us avoid
temptation, and make firm commitments to change.
Value judgments and willpower
New York's big drink debate
Pinpointing complex
behaviors in the brain isn't simple; we weren't born with the words
"impulsivity" and "willpower" etched into particular places on our
heads. Scientists are still in the early stages of figuring out how
billions of cells called neurons generate particular outcomes, and which
circuits do what. But some clues have emerged from recent experiments.
When people who are
trying to lose weight are confronted with meal choices, it appears there
are two major factors in their decision: taste and health, said Todd Hare, assistant professor of neuroeconomics at the University of Zurich.
Hare's research
shows that dieters who successfully turn down fatty temptations such as
ice cream put more emphasis on the healthiness of food and relatively
less emphasis on the taste.
It is the opposite for
dieters who can't say "no" to sweets, he said. They say they're trying
to eat healthy, but "they seem unable to shift away from the more
automatic, stronger representation of taste," Hare said.
By using functional
magnetic resonance imaging, or fMRI, scientists can see how a brain
region called the ventral medial prefrontal cortex becomes active in
valuing options in predicaments like this.
The ventral medial
prefrontal cortex also appears to get involved in certain monetary
decisions -- for instance, when researchers present participants with
the choice of accepting a large reward later or a smaller reward
immediately. Hare's research on this is not yet published, but the
phenomenon was described in a 2011 research review.
Scientists have also
located a second important brain area for these kinds of decisions: the
dorsolateral prefrontal cortex. There is more activity in this region
when participants choose options that appear better for them in the long
run -- the healthy food item or the larger monetary reward that will
arrive later.
The interaction between
these two brain regions -- the ventral medial prefrontal cortex and the
dorsolateral prefrontal cortex -- is stronger for people who show
greater self control with either money or food, Hare said.
"They're working together to shape the way you're going to make your choices."
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Scientists are also investigating brain areas associated with turning down temptations.
University of Cambridge
neuroscientist Molly Crockett and her colleagues suggested in a study
earlier this year that "precommitment" -- voluntarily restricting one's
access to temptation -- is more effective at promoting self control than
willpower.
In the experiment, men
viewed erotic images that they rated according to personal preference.
Then, in one task, they could decide in advance that they would not have
the option to see the images they rated poorly. In exchange, they could
see the higher-rated images after a greater time delay. This is called
"precommitment."
In a different task, men
were challenged to use willpower to actively resist viewing the
lower-rated images while they waited for the higher-rated images.
Precommitment appeared to be a better strategy on average.
In impulsive
participants in particular, researchers saw more activation in the
ventral striatum and ventromedial prefrontal cortex areas during
precommitment. These relationships between brain activation patterns and
impulsive tendencies suggest that people in general may have some
self-awareness about their own self-control abilities.
Are self control
problems, such as overeating and overspending, the result of poor
willpower or impaired ability to precommit, or both? Further research on
these issues could help the development of behavioral or
pharmacological interventions, according to the study.
Can we alter brain function for the better?
Currently, we don't have drugs designed to target such brain impairments associated with lack of self control.
But, in theory, a drug
of the future could stimulate key brain areas to help people with
self-control problems diet or save money, according to David Laibson,
professor of economics at Harvard University.
If that sounds too much
like science fiction, consider that many drugs are already on the market
to alter brain function for the better -- for example, methylphenidate
(Ritalin) for attention deficit disorder and anti-depressants for
depression.
Outside the pharmacy,
there is a drug to combat exhaustion and enhance attention, used by
millions of Americans every day: caffeine. Laibson argued that if these
substances are widely accepted, why shouldn't there be options for
people who want better control of their food decisions?
The practical realities
for a self-control drug are complex, however. Hare cautioned that these
brain areas would be hard to target with medicine because a lot of other
brain areas would be hit at the same time. No drug could selectively
increase activity in the dorsolateral prefrontal cortex alone, for
example.
A different approach,
which has not been tried, would be to use transcranial magnetic
stimulation to temporarily enhance the activity of regions of the brain
near the skull. This technique -- in which magnetic fields generate
small electrical currents, activating cells in a specified part of the
brain -- is being explored for depression patients who don't respond to
medication.
A 2010 Nature Neuroscience study
used transcranial magnetic stimulation to temporarily inhibit the
dorsal lateral prefrontal cortex, and showed that this led to
participants making more impatient decisions.
Theoretically, this
technology could be applied in the opposite way -- to train relevant
brain circuitry to come online during problematic food choices among
dieters, so that eventually the person's brain would respond naturally
in this way, Hare said.
"If there's enough
success with this in conditions such as depression, then I could see
that that would be the logical next step," Hare said.
Scientists may also be
able to develop behavioral interventions based on brain research -- i.e.
how to train and promote self-control. Psychologists, for example, may
be able to derive behavioral therapies from the "brain circuit
differences that we see in people with different kinds of self control
problems," said Joshua Buckholtz, assistant professor of psychology at
Harvard University.
Buckholtz has
unpublished research suggesting that people with high BMIs and non-obese
impulsive people have similar brain chemistry patterns.
Committing to change
To recap: We're bad at
self control. Scientists are looking at the brain to figure out how self
control breaks down at the neurological level. Such insights could
directly lead to interventions in the form of pharmaceuticals or brain
stimulation.
In the meantime, what can we do to help ourselves behave more in line with our good intentions, even in the face of temptations?
"The more we recognize
the commonality of this problem, the more prepared we'll be to develop
solutions to solve a problem, because the solutions end up being the
same across all the different domains," Laibson said.
The basis of
nonpharmaceutical solutions is the big C-word: commitment. To some
extent, most of us are already entrenched in a system of commitments
that keep us in line. It's called the workplace.
Journalists publish
articles, cashiers scan groceries and teachers grade papers because of
systems built into our society that commits them to perform certain
tasks, with the threat of punishment -- or not getting paid -- looming
over their heads, Laibson said. Managerial structures ensure that
employees at every level do what they're supposed to be doing.
"We built this system
that is actually well tuned to who we are psychologically," he said.
"We're not relying completely on our willpower to do everything. We are
letting the system take care of us."
When it comes to money,
for instance, many companies offer savings plans that automatically
place a fixed percentage of your paycheck into a 401(k) account, with
strict penalties if you try to access that money before retirement. Once
you sign up, you don't have to think about making the choice every
week; it just happens in the background.
"We don't want people to
tell us what to do so that we have no freedom, but we do need a little
bit of help so that we actually get to work and have a productive day
instead of rolling in at 11 a.m.," Laibson said.
Applying that method to
food is a lot trickier. Your boss can make you go to a 9 a.m. meeting,
but you don't have a Food Manager who prods you to avoid potato chips
and count calories at every single meal. Even if your workplace's
cafeteria has reasonably sized portions, including small desserts, no
one will stop you from buying two or three cookies.
To encourage healthy
habits in an already structured workplace, companies could instead
institute standing desks and hold standing or even "walking meetings,"
in which people move around while they discuss business instead of sit
in a conference room. These interventions should, however, be tested
scientifically before being widely promoted, Laibson said.
Government intervention is another way that self control could be imposed, but a controversial one. The city of New York tried to limit sugary drinks sold to 16 ounces each last year, but an appeals court ruled in July
that this was "arbitrary and capricious." In Laibson's view, such a
policy needs scientific evidence that it has positive health outcomes
before being broadly enacted.
But you don't
necessarily need a boss or government official threatening to punish you
for breaking rules you already want to follow for the sake of your
health. You can set up a system in which you discipline yourself.
Through the Internet,
you can wager your own money to commit yourself to your own diet and
exercise aspirations. A website called StickK
allows you to put your own money on the line in support of whatever
goal you may have; if you don't fulfill it, you lose the money. As Yale
economist Dean Karlan, co-founder of StickK, told CNN in 2008, "It's a contract to make slothfulness more expensive."
So, think how much money
your health-conscious self would offer your sweet-tooth self to keep
the ice cream in the freezer, or not buy it at all.
Change can start today.
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