Research shows brain's ability to overcome pain and thirst

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Research shows brain's ability to overcome pain and thirst

http://www.news-medical.net/?id=15683

Researchers at Melbourne's Florey Institute have discovered

how the brain prioritises pain and thirst in order to survive - a

mechanism that helps elite athletes to 'push through the pain

barrier'.

The Florey's Dr Farrell and colleagues discovered that pain

sensitivity is enhanced when people are thirsty.

The scientists also found that a part of the brain is uniquely

activated when pain and thirst are experienced together, suggesting

these regions may act as an integrative centre that has a special

role in modifying pain senses.

Dr Farrell used PET (Positron Emission Tomography) scans to examine

changes in brain activity. The 10 individuals participating in the

study were given saline injections to stimulate mild thirst and thumb

pressure to induce mild pain. Although the level of thumb pressure

remained constant throughout the tests, as people became thirstier,

they felt more pain.

Dr Farrell said the regions of the brain (the pregenual cingulate

cortex and ventral orbitofrontal cortex) activated together during

thirst and pain acted like a priority switch.

" Depending on internal demands being placed on the body, the brain

needs to decide which demand is more important to respond to in order

to survive, " he said.

" Many elite athletes have an ability to balance their priority switch

longer than most people so they can push through normal thresholds of

pain and thirst whilst competing. "

" But when the internal demands become extreme and the body's

physiology is too perturbed, the brain will tell the body 'enough is

enough,' " Dr Farrell said.

The brain's ability to overcome pain and thirst is witnessed in a

soon-to-be released IMAX film: Wired to Win: Surviving the Tour De

France. This film shows how the human brain allows elite athletes to

compete and push themselves to a limit beyond our imagination.

The Florey Institute, with the generous support of IMAX, is

holding a free special screening of the new IMAX movie, Wired to Win

at 6:30pm on 28 February. This event is open to the public, but seats

are strictly limited. Contact Sanam Sharma on email:

wiredtowin@... or phone: (03) 8344 1642 to secure your

ticket.

This research paper, " Unique, common and interacting cortical

correlates of thirst and pain " was prepared by J. Farrell

( Florey Institute), F. Egan ( Florey Institute),

Zamarripa (Research Imaging Center, San , Texas),

Shade (South West Foundation for Biomedical Research, San ,

Texas), Blair-West (University of Melbourne), Fox

(Research Imaging Center, San , Texas), and A. Denton

(University of Melbourne). It was published today in Proceedings of

the National Academy of Sciences.

The Florey Institute is Australia's leading brain research

centre. Its scientists undertake clinical and applied research that

can be developed into treatments to combat brain disorders, and new

medical practices. Their discoveries will improve the lives of those

directly, and indirectly, affected by brain and mind disorders in

Australia, and around the world. The Florey's research areas cover a

variety of brain and mind disorders including Parkinson's disease,

stroke, motor neuron disease, addiction, epilepsy, multiple

sclerosis, muscular dystrophy, autism and dementia.

http://www.hfi.unimelb.edu.au