Navigation Links
Free will takes flight: how our brains respond to an approaching menace
Date:8/24/2007

Wellcome Trust scientists have identified for the first time how our brain's response changes the closer a threat gets. Using a "Pac Man"-like computer game where a volunteer is pursued by an artificial predator, the researchers showed that the fear response moves from the strategic areas of the brain towards more reactive responses as the artificial predator approaches.

When faced with a threat, such as a large bear, humans, like other animals, alter their behaviour depending on whether the threat is close or distant. This is because different defence mechanisms are needed depending on whether, for example, the bear is fifty feet away, when being aware of its presence may be enough, or five feet away, when we might need to fight or run away.

To investigate what happens in the brain in such a situation, researchers at the Wellcome Trust Centre for Neuroimaging at UCL, London, created a game where subjects were chased through a maze by an artificial predator if caught, they would receive a mild electric shock. The researchers then measured their brain activity using functional magnetic resonance imaging (fMRI). The results are published today in the journal Science.

When the artificial predator was in the distance, the researchers observed activity in lower parts of the prefrontal cortex just behind the eyebrows. Activity in this area known as the ventromedial prefrontal cortex increases during anxiety and helps control strategies on how to respond to the threat.

However, as the predator moved closer, the brain activity shifted to a region of the brain responsible for more primitive behaviour, namely the periaqueductal grey. The periaqueductal grey is associated with quick-response survival mechanisms, which include fight, flight and freezing. This region is also associated with the body's natural pain killer, opioid analgesia, preparing the body to react to pain.

Dr Dean Mobbs from UCL, lead author on the study, says: "Without fear, animals would not react to threats. This is a poor survival strategy and makes it more likely that the animal will be eaten and not pass on its genes.

"The most efficient survival strategy will depend on the level of threat we perceive. This makes sense as sometimes being merely wary of a threat is enough, but at other times we need to react quickly. The closer a threat gets, the more impulsive your response will be in effect, the less free will you will have."

Although this natural defence mechanism is beneficial in evolutionary terms, Dr Mobbs believes that malfunctions in the system might help explain why some people suffer from anxiety disorders and panic attacks.

"When our defence mechanisms malfunction, this may result in an over-exaggeration of the threat, leading to increased anxiety and, in extreme cases, panic," says Dr Mobbs. "Although brain-imaging studies like ours cannot directly help to cure such disorders, they do improve our understanding of how the emotional system operates. This is the first step to helping people with anxiety-related disorders."


'/>"/>
Contact: Craig Brierley
c.brierley@wellcome.ac.uk
44-207-611-7329
Wellcome Trust
Source:Eurekalert

Related medicine news :

1. India takes on foot-and-mouth disease by vaccinating animals
2. Roller coaster takes brain for a big ride!!
3. Children! Protecting them from medical mistakes
4. World Health Organisation Takes a Historic Decision and Approves Treaty to Discourage Smoking
5. World Health Organisation Takes a Historic Decision and Approves Treaty to Discourage Smoking
6. World Health Organisation Takes a Historic Decision and Approves Treaty to Discourage Smoking
7. Men who takes risk is unlikely to impress women
8. Research on HIV takes new direction
9. Bhitarkanika Sanctuary In Orissa Takes Precaution To Monitor Bird Flu
10. Government Takes Tough Stand Against Falling Sex Ratio
11. Bill Gates Takes Personal Interest in AIDS Program
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/12/2017)... , ... October 12, 2017 , ... Planet Fitness, one ... U.S., announced today its plans to open a flagship location in Covington, LA at ... former Rooms To Go store next to Office Depot in the Holiday Square shopping ...
(Date:10/12/2017)... ... 2017 , ... The American College of Medical Informatics (ACMI) will present the ... Opening Session of AMIA’s Annual Symposium in Washington, D.C. AMIA’s Annual Symposium ... a pioneer in the field of medical informatics, this prestigious award is presented to ...
(Date:10/12/2017)... ... October 12, 2017 , ... Dr. Parsa Mohebi, ... a medical article to the newly revamped Cosmetic Town journal section, ... hair transplant procedure known as Follicular Unit Extraction (FUE). , Dr. ...
(Date:10/12/2017)... ... October 12, 2017 , ... On Saturday, October 21, the Health ... Miles by Moonlight to raise money for the American Heart Association Heart Walk. Teams ... Teams will work together to keep their treadmills moving for 5 hours. Treadmills will ...
(Date:10/12/2017)... ... October 12, 2017 , ... In the United States, single-family ... some states—like New York, New Jersey, Massachusetts, Texas, Virginia, Connecticut, and California—the average ... extremely low property-tax rates, which contributes to the relatively lower cost of living ...
Breaking Medicine News(10 mins):
(Date:9/27/2017)... 27, 2017  Commended for their devotion to personalized service, ... as number one in the South Florida Business Journal,s 50 ... 5000 yearly list, the national specialty pharmacy has found its ... will soon be honored by SFBJ as the 2017 ... Set to receive his award in October, Bardisa said ...
(Date:9/23/2017)... Sept. 22, 2017 Janssen Biotech, Inc. (Janssen) ... letter from the U.S. Food and Drug Administration (FDA) ... sirukumab for the treatment of moderately to severely active ... clinical data are needed to further evaluate the safety ... active RA. ...
(Date:9/19/2017)...   ZirMed Inc ., a recognized leader in cloud-based ... has been ranked #1 by its users for the seventh ... User Survey. ZirMed was recognized as the top-ranked end-to-end revenue ... centers over 200 beds and holds one of the longest ... history. ...
Breaking Medicine Technology: