A study done by psychologist Walter Mischel at Stanford in the sixties has long been a classic. But it takes on dramatically increased significance with the growth of our understanding of brain plasticity in the last two decades of neuroscience.

In this study, preschoolers were seen in a small room with their mothers. The experimenter put a marshmallow on the table and told the child he can eat it right away. Or, if the child can wait until the experimenter and the child’s mother return to the room, he will get an additional marshmallow. The kids had nothing else to do in the room but wait, no way to distract themselves from the temptation to just go ahead and eat the yummy treat now.

The majority of children were unable to wait the maximum time of 15 or 20 minutes, and ate the marshmallow. The average time kids could wait was 6 minutes.

Here’s where the story gets interesting: the research team followed the kids into adulthood. They found that those who could exercise greater self control and delay gratification for longer periods of time had greater confidence, better interpersonal skills, higher SAT scores, reduced incidence of substance abuse, and many other positive life outcomes.

These findings suggest that “the marshmallow test” is ‘‘an early indicator of an apparently long-term personal quality’’(Mischel et al., 1988, 2011) that leads to myriad positive outcomes in life. A child who possesses more self-control can resist fleeting temptations to pursue difficult goals throughout life. In contrast, children with less self-control fail to persist toward these goals and thus achieve less.

Note a key element in the interpretation here: the capacity (and incapacity) for self-control is a “long term personal quality”. Implied but not explicitly stated here is that this capacity is more or less fixed. Long term. Either you got it or you don’t.

We know now what Dr. Mischel and colleagues did not in the 60’s – that the brain the constantly reshaped by experience. It is plastic, moldable, shapeable. This experience-dependent change takes place in neural pathways and in the broad connectivity of these pathways in neural networks. It occurs on many levels, from cellular changes in learning to larger scale changes in neural activiation and coordination due to highly repetitive (expert) experience.

This fascinating story of neuroplasticity is described in several great books, including:

• Train Your Mind, Change Your Brain: How a New Science Reveals Our Extraordinary Potential to Transform Ourselves. by Sharon Begley
• The Mind and the Brain: Neuroplasticity and the Power of Mental Force by Jeffrey M. Schwartz and Sharon Begley
The Brain That Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science by Norman Doidge