THURSDAY, May 4, 2006 (HealthDay News) -- An experiment funded by the National Institute on Drug Abuse finds that feeling dread about an approaching event is a question of how much attention you pay to that event.
Why should the National Institute on Drug Abuse be concerned with the brain mechanisms behind dread?
Because dread is "an issue about decision-making," said Dr. Gregory Berns, lead author of a report on the experiment in the May 5 issue of Science. "We all make decisions based on expectations of the future. We're interested in how and why people make decisions to use drugs. Addiction is a disorder of decision-making."
The decision that Berns and his colleagues at Emory University School of Medicine asked 32 volunteers to make was whether they would prefer a large electric shock quickly or would prefer to wait for a lesser shock.
The volunteers first got mild electrical shocks to the foot. The voltage was gradually increased until it reached the level that each participant said was the maximum that could be tolerated. Then each participant was told how painful the next shot would be, and was also told the voltage would be lower and the pain would be less if they waited a while.
Some people in the study dreaded the prospect of having a shock so much that they preferred not to wait for the lesser shock, but to have more pain quicker. "A subset of people didn't want to wait," said Berns, who is an associate professor of psychiatry and behavioral sciences at Emory. "They dreaded it so much that they preferred a bigger shock sooner. That is irrational behavior."
Magnetic resonance imaging (MRIs) showed that the brain activity related to that feeling of dread occurred in specific areas of the pain network -- areas linked to attention. There's a practical use for that information in everyday life, Berns said.
Anyone can apply the finding that dread of a forthcoming event is related to the amount of attention an individual pays to that event, he said, noting that "everyone experiences things they don't like and have to do anyway." The annual flu shot, the visit to the dentist, the recommended colonoscopy for early detection of colorectal cancer are examples.
"Dread is a state of mind that affects behavior," Berns said. "Understand what goes into making you dread something can help you overcome it. We can say that if you distract yourself, your dread will go down."
The experiment built on a whole discipline of brain scanning that has identified a wide variety of brain centers, including those involved with pain, Berns said. And the new finding has possible application to economics.
"It helps in economics because economics deals with decision-making," he said. "For example, it is standard economic theory that time degrades the value of things. It is better to get $100 now than to wait a year for the $100. Also, the theory is that with things that are bad, you should postpone them as long as possible. We can test that theory, as well as alternative theories about the value or cost of waiting itself."
More information
MRI brain scans are described by the Radiology Society of North America.
