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:4/28/2017)... ... April 28, 2017 , ... ... with the Home Care Association of America (HCAOA). This agreement allows HCAOA members ... services, as well as discounts on Accreditation University (AU) educational resources that help ...
(Date:4/28/2017)... (PRWEB) , ... April 28, 2017 , ... ... to announce the integration of Microsoft(R) Word(TM) Online(TM), which enables sleep physicians to ... since it streamlines the reporting process and provides a familiar interface that does ...
(Date:4/28/2017)... ... 2017 , ... Horizon Blue Cross Blue Shield of New Jersey (BCBSNJ) announced ... its outlook as “stable.” At the same time, the ratings agency cautioned that the ... dip below “capital adequacy” thresholds required for its strong rating. , “Horizon is committed ...
(Date:4/28/2017)... ... April 28, 2017 , ... GlycoMark, Inc. announced today ... throughout the Northeast U.S. , GlycoMark is the only clinically available blood ... provides a clinically proven one- to two-week measure of hyperglycemic excursions, often related ...
(Date:4/28/2017)... ... April 28, 2017 , ... Ushio America ... lamps offer an instant energy-saving solution for F32T8 fluorescent lamps on most instant-start ... ballasts. These 50,000 hour rated lamps utilize the existing electronic ballast, saving labor ...
Breaking Medicine News(10 mins):
(Date:4/24/2017)... 2017 Solentim, the developer of instrumentation ... of a major new product line called the ... VIPS has been developed for automatically seeding single ... part of the process to generate clonally-derived cell ... more reliable solution when compared to traditional single ...
(Date:4/20/2017)... , April 20, 2017 ... "Global Biosimilar Pipeline and Market Prospects: Addressing Production ... report to their offering. ... "Global Biosimilar Pipeline and Market Prospects: ... Design" provides an in-depth assessment of the current trends ...
(Date:4/20/2017)... April 20, 2017  AbbVie (NYSE: ABBV), a ... (n=145/146) of chronic hepatitis C virus (HCV) infected ... 6 and compensated cirrhosis (Child-Pugh A) achieved sustained ... ) with its investigational, pan-genotypic regimen of glecaprevir/pibrentasvir ... seen following 12 weeks of G/P treatment without ...
Breaking Medicine Technology: