THE BIOLOGY OF SUCCESS
Are Some
of Us Wired
to Achieve?
Yes, the brain has “success centers”
—but neural plasticity allows it to
reshape and improve itself
By Markham Heid
T
he “marshmallow test” may be the most fa-
mous behavioral-science experiment in history. In
it, a child is presented with a marshmallow or a simi-
lar treat. The child is told that if she can wait 15 min-
utes before eating the marshmallow, she’ll receive a second one.
Stanford University researchers conducted the original
marshmallow tests in the late 1960s and early 1970s. Initially, the
aim of these tests was to determine the age at which kids develop
the ability to show patience and delay gratification. (The test
was normally administered to children between ages 4 and 6.)
But follow-up studies found that the youngsters who were able
to resist gobbling up the marshmallow were better able to cope
with stress during adolescence, were better at taking standard-
ized tests and were more likely to excel academically and pro-
fessionally. Basically, the kids who could muster self-restraint
early in life often turned out to be successful teens and adults.
Although groundbreaking, the Stanford marshmallow test
has lately come under scrutiny. When researchers at New York
University and the University of California, Irvine, repeated
the test in 2018 with a larger and more socioeconomically di-
verse group of kids, they found that the ability to exert “im-
pulse control” only partly predicted greater achievement later
in life. Adjusting for variables such as background and up-
bringing reduced the effect. Still, the marshmallow test re-
vealed that at a very early age, the brains of some children may
