That dreadful feeling - most choose more pain sooner rather than less later

May 9 2006

According to research into why people experience the feeling of dread, a team of Emory neuroscientists led by Gregory Berns, MD, PhD, used functional magnetic resonance imaging (fMRI) to determine the areas of the brain that are activated when someone gets that dreadful feeling.

The study was part of a research program in the growing field of neuroeconomics, an area in which neuroscience methods are being applied to economic questions.

Dr. Berns, an associate professor in the Department of Psychiatry and Behavioral Sciences at Emory University School of Medicine says when a person experiences the dread of having something hanging over their head it is often worse than the event being itself.

Berns says it is a commonplace experience, but standard economic models of decision-making do not deal with the issue, so, they took a biological approach in order to see what happens in the brain when this happens.

The study was conducted using an fMRI scanner to look at the brains of the study participants while delivering a series of low voltage shocks to the foot of each participant, with different levels of intensity and different time delays up to the shock.

Each of the participants in the study was screened to determine their maximal pain threshold.

While in the MRI scanner, participants underwent a series of 96 shocks.

Before each shock, they were told how painful the shock would be (as a percent of their threshold) and how long they would have to wait for it.

After the scanning procedure, they were then given the opportunity to choose between different intensity-delay combinations, the choice was always between more pain sooner or less pain later.

The degree to which individuals chose more voltage sooner just to get a trial over was an indication of the dread they experienced from waiting.

A total of 32 participants took part in the trial. Most of the participants preferred to speed up the waiting period and were deemed "mild dreaders", but 28%, the "extreme dreaders", dreaded so much that they were willing to take more pain just to avoid waiting.

The scans showed that brain activity related to dread was localized in the areas of the brain associated with pain. Dread was found in the parts of the pain network linked to attention and this is important because it suggests that dread is not as simple as fear or anxiety, emotions which are controlled by different brain regions.

The findings also showed that the mild and extreme dreaders had different patterns of brain activity.

The extreme dreaders had more activity in the attentional parts of the pain matrix, and this activity was seen much earlier in each trial compared to the mild dreaders.

Dr. Berns says the key factor seems to be that extreme dreaders devoted more attention toward the part of their body that was about to be shocked.

It also means that dread can be mitigated by diverting attention with meditation or another activity.

Berns says the benefits could be substantial if it means that a person acts more rationally in terms of getting healthcare, or simply decreasing the psychological toll of dread and anxiety."

The study, which was supported by the National Institutes of Drug Abuse (NIDA), was published in the May 5, 2006 issue of the journal Science.