Research shows why some soldiers are cool under fire

U.S. soldiers walk on shattered glass at the site a bomb attack in Baghdad's Sadr City February 15, 2009.

CHICAGO (Reuters) - Soldiers who perform best under extreme stress have higher levels of chemicals that dampen the fear response, a finding that could lead to new drugs or training strategies to help others cope better, a U.S. researcher said on Sunday.

"There are certain individuals who just don't get as stressed. Their stress hormones are actually lower," Deane Aikins of Yale University in New Haven, Connecticut, told reporters at the American American Association for the Advancement of Science meeting in Chicago.

Aikins and colleagues at Yale study stress hormone levels of soldiers undergoing survival training, which includes mock prisoner of war experiences.

Blood samples taken from soldiers in the training programs showed those who fared best under extreme stress had lower levels of the stress hormone cortisol and higher levels of neuropeptide y, a chemical that dampens the body's stress response.

"All of the recovery hormone systems, all of the systems that turn it down, really kick in for these resilient individuals," Aikins said.

"The question is how do you get folks who aren't as cool in stress trained up?"

Aikins and colleagues now are studying whether giving other soldiers a dose of this stress-dampening neuropeptide might help people fare better in combat situations.

He said mental training exercises such as meditation also might help improve the performance of soldiers under stress.

(Editing by Bill Trott)