BBC NEWS Americas Africa Europe Middle East South Asia Asia Pacific
BBCi NEWS   SPORT   WEATHER   WORLD SERVICE   A-Z INDEX     

BBC News World Edition
 You are in: Health  
News Front Page
Africa
Americas
Asia-Pacific
Europe
Middle East
South Asia
UK
Business
Entertainment
Science/Nature
Technology
Health
Medical notes
-------------
Talking Point
-------------
Country Profiles
In Depth
-------------
Programmes
-------------
BBC Sport
BBC Weather
SERVICES
-------------
EDITIONS
Tuesday, 15 October, 2002, 00:38 GMT 01:38 UK
Brain switch 'could control fear'
Woman with pills
Thousands suffer from anxiety disorders
The discovery of a chemical mechanism which appears to play a key role in the human fear response holds the promise of drugs to treat anxiety.

Thousands of Britons suffer from anxiety disorders, ranging from phobias and obsessive compulsive disorders to more generalised anxiety problems.

These can severely damage quality of life, with some suffering regular panic attacks, or almost constant "nervous" symptoms such as sweating, raised heart rate and churning stomach.


Anxiety is a completely natural response - and we need it

Dr Allan Norris, consultant clinical psychologist
A team of researchers from the University of California at Los Angeles say they have found a "switch" in the brain which seems to be important in overcoming fear.

This opens the possibility of new medications to help control anxiety disorders.

The chemical brain switch - a "voltage-gated calcium channel" - is already known to scientists, but was not previously thought to have a role in fear.

Electric shock

However, tests on a group of volunteers suggest otherwise.

The volunteers were "taught" to associate the playing of a tone with a mild electric shock.

This created a "conditional" fear - similar to a phobia, in which hearing the tone would produce a mild anxiety.

If the tone is played repeatedly, but without the electric shock, the brain "re-learns" not to be anxious about it.

However, if a drug which inhibits the chemical brain switch was given, the brain was able to learn the initial "conditional" response - but not to "unlearn" it when the electric shock was removed.

In theory, this means that the switch has a particular role in helping the brain overcome an anxiety it has already learned.

It also means that if scientists could improve the efficiency of this brain process with a drug instead of blocking it, it might be easier for people with anxiety disorders to control their conditions.

Response needed

Dr Mark Barad, from the research team, said: "Brain plasticity, or the ability of the central nervous system to modify cellular connections, has long been recognised as a key component to learning and memory.

"The discovery of a distinct molecular process in overcoming fear bodes well for development of new drugs that can make psychotherapy, or talk therapy, easier and more effective in treating anxiety disorders."

The "treatment of choice" for many anxiety disorders is cognitive psychotherapy, which can be supplemented by tranquilisers or antidepressants in more severe cases.

However, Dr Allan Norris, a consultant clinical psychotherapist from the Nuffield Hospital in Birmingham, said that any drug should not remove anxiety completely.

He said: "Anxiety is a completely natural response - and we need it, or we would be putting ourselves in dangerous situations.

"It's a bit like pain - we don't like it but it's a very necessary thing."

See also:

20 Dec 00 | Medical notes
02 Oct 02 | Health
04 Sep 02 | Health
Internet links:


The BBC is not responsible for the content of external internet sites

Links to more Health stories are at the foot of the page.


E-mail this story to a friend

Links to more Health stories

© BBC ^^ Back to top

News Front Page | Africa | Americas | Asia-Pacific | Europe | Middle East |
South Asia | UK | Business | Entertainment | Science/Nature |
Technology | Health | Talking Point | Country Profiles | In Depth |
Programmes