Our brains are wired to pay more attention to things that have previously brought us pleasure—a bias that may explain why it’s so hard to break bad habits or stick to New Year’s resolutions.
Neuroscientists demonstrated that when people see something associated with a past reward, their brain flushes with the neurotransmitter chemical dopamine—even if they aren’t expecting a reward and even if they don’t realize they’re paying that thing any attention. The results suggest we don’t have as much self-control as we might think.
“We don’t have complete control over what we pay attention to,” says senior author Susan M. Courtney, professor of psychological and brain sciences at Johns Hopkins University. “We don’t realize our past experience biases our attention to certain things.”
This could be why it’s so hard to break a pleasurable addiction and why dieters keep thinking about fattening food when they’re trying to eat better.
“I could choose healthy food or unhealthy food, but my attention keeps being drawn to fettuccini alfredo,” Courtney says. “What we tend to look at, think about, and pay attention to is whatever we’ve done in the past that was rewarded.”
For the study, published in Current Biology, researchers asked 20 participants to find red and green objects on a computer screen filled with different colored objects. Participants got $1.50 for finding red objects and 25 cents for green ones. The next day, while the subjects had brain scans, researchers asked them to find certain shapes on the screen.
Continue reading to learn what happened then…