Neurobiology of dread gives scientists clues about human decision making

May 04, 2006

ATLANTA -- In order to better understand how people make decisions when the outcomes are known to be unpleasant, 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 experiences dread. 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. 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.

"Most people don't like waiting for an unpleasant outcome, and want to get it over with as soon as possible," explains Dr. Berns, an associate professor in the Department of Psychiatry and Behavioral Sciences at Emory University School of Medicine. "The only explanation for this is that the dread of having something hanging over your head is worse than the thing that you are dreading. It is a commonplace experience, but standard economic models of decision-making don't deal with this issue. So, we decided to take a biological approach and see what happens in the brain that might cause people to make such rash decisions."

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% dreaded so much that they were willing to take more pain just to avoid waiting. Berns called them "extreme dreaders."

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. This is important because it suggests that dread is not as simple as fear or anixiety, which are emotions 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.

"Taken together, the anatomical locations of dread responses suggest that the subjective experience of dread that ultimately drives an individual's behavior comes from the attention devoted to the expected physical response, and not simply a fear or anxiety response," explains Dr. Berns. "The key factor seems to be that extreme dreaders devoted more attention toward the part of their body that was about to be shocked. This is important because it means that dread is not quite the same as fear or anxiety. These findings underscore the very real nature of dread and the need to account for it in economics."

It also means that dread can be mitigated by diverting attention.

"The dread associated with things like medical procedures or public speaking, while real, can probably be alleviated by diverting one's attention during the waiting period," says Dr. Berns. "There may be many ways to do this, ranging from meditation to sports, or even a movie. The benefits could be substantial if it means that we act more rationally in terms of getting healthcare, or simply decreasing the psychological toll of dread and anxiety."
-end-


Emory University Health Sciences Center

Related Brain Activity Articles from Brightsurf:

Inhibiting epileptic activity in the brain
A new study shows that a protein -- called DUSP4 -- was increased in healthy brain tissue directly adjacent to epileptic tissue.

What is your attitude towards a humanoid robot? Your brain activity can tell us!
Researchers at IIT-Istituto Italiano di Tecnologia in Italy found that people's bias towards robots, that is, attributing them intentionality or considering them as 'mindless things', can be correlated with distinct brain activity patterns.

Using personal frequency to control brain activity
Individual frequency can be used to specifically influence certain areas of the brain and thus the abilities processed in them - solely by electrical stimulation on the scalp, without any surgical intervention.

Rats' brain activity reveals their alcohol preference
The brain's response to alcohol varies based on individual preferences, according to new research in rats published in eNeuro.

Studies of brain activity aren't as useful as scientists thought
Hundreds of published studies over the last decade have claimed it's possible to predict an individual's patterns of thoughts and feelings by scanning their brain in an MRI machine as they perform some mental tasks.

A child's brain activity reveals their memory ability
A child's unique brain activity reveals how good their memories are, according to research recently published in JNeurosci.

How dopamine drives brain activity
Using a specialized magnetic resonance imaging (MRI) sensor that can track dopamine levels, MIT neuroscientists have discovered how dopamine released deep within the brain influences distant brain regions.

Brain activity intensity drives need for sleep
The intensity of brain activity during the day, notwithstanding how long we've been awake, appears to increase our need for sleep, according to a new UCL study in zebrafish, published in Neuron.

Do babies like yawning? Evidence from brain activity
Contagious yawning is observed in many mammals, but there is no such report in human babies.

Understanding brain activity when you name what you see
Using complex statistical methods and fast measurement techniques, researchers found how the brain network comes up with the right word and enables us to say it.

Read More: Brain Activity News and Brain Activity Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.