In today’s world, patience and self-discipline can be a challenge. New research probes why is it so hard for some people to resist the least little temptation, while others seem to possess incredible patience, passing up immediate gratification for a greater long-term good.
Investigators from Washington University in St. Louis believe the answer is that some people think about future rewards or benefits — that is how good they will feel in the future from passing up a smaller immediate reward.
Researchers came to this conclusion from performing brain imaging studies that found activity in two regions of the brain distinguished impulsive and patient people.
“Activity in one part of the brain, the anterior prefrontal cortex , seems to show whether you’re getting pleasure from thinking about the future reward you are about to receive,” said study co-author Todd Braver, Ph.D.
“People can relate to this idea that when you know something good is coming, just that waiting can feel pleasurable.”
Investigators designed the study, published in the Journal of Neuroscience, to examine what happens in the brain as people wait for a reward.
Researchers were interested in the response of people characterized as “impulsive,” and if they would show different brain responses than those considered “patient.”
Unlike previous research on delayed gratification that had people choose between hypothetical rewards of money over long delays (e.g, $500 now or $1,000 a year from now), this Washington University study presented their participants with real rewards of squirts of juice that they chose to receive either immediately or after a delay of up to a minute.
“It’s kind of funny because we treated the people in our study like researchers that work with animals do, and we actually squirted juice into their mouths,” Braver said.
Results show that a brain region called the ventral striatum (VS) ramped up its activity in impulsive people as they got closer and closer to receiving their delayed reward. The VS activity of patient people, on the other hand, stayed more constant.
The researchers interpreted these different brain responses to mean that impulsive people initially did not find the prospect of waiting for a reward very appealing.
However, as they approached the time they’d receive that reward, they became more excited and their VS reflected that excitement.
“This gradual increase may reflect impatience or excessive anticipation of the upcoming reward in impulsive individuals,” said researcher Koji Jimura, Ph.D. This was unlike patient people, who were likely content with waiting for the reward from the start, as no changes in VS activity were observed for them.
Investigators believe a unique finding concerned the anterior prefrontal cortex (aPFC). This is the part of the brain that helps you think about the future.
They discovered that the patient people experienced heightened activity in the aPFC when they first started waiting for a reward, which then decreased as the time to receive the reward approached.
Impulsive people didn’t show this brain activity pattern.
“The aPFC appears to allow you to create a mental simulation of the future. It helps you consider what it’ll be like getting the future reward. In this way, you can get access to the utility and satisfaction in the present,” said Braver.
By thinking about the future reward, patient people were able to gain what economists call “anticipatory utility.” While their reward was far away in time, they were giddy with anticipation in the present.
Conversely, impulsive people weren’t thinking beyond the present and so did not feel pleasure when they were told they had to wait. Their excitement built only as they got closer to receiving their reward.
Researchers believed the study suggests that people may be impulsive because they do not or cannot imagine the future, so they prefer rewards right away. According, this insight may help in the assessment of clinical treatments for impulsivity problems –including problem gambling and substance abuse disorders.
A similar brain imaging approach as was used in the Washington University study could allow clinicians to track the effects of an intervention on changes not only in impulsive behavior but also changes in patients’ brain responses.
“One possible treatment approach could be to enhance mental functions in aPFC, a brain region well-known to be associated with cognitive control,” said Jimura. By increasing cognitive control, impulsive patients could learn to reject their immediate impulses.
Impulsivity occurs not only in a clinical setting but also every day in our own lives. Applying his research to his personal life, Braver said, “When I’m successful at achieving long-term goals it’s from explicitly trying to activate that goal and imagining each decision as helping me achieve it, to keep me on track.”
Researchers believe adopting a strategy of focusing on the long-term could help anyone move past present distractions and move toward our future goals.