The Nobel Prize in the field of physiology or medicine has been awarded to US scientists David Julius and Ardem Patapoutian.

They were cited for their discovery of receptors for temperature and touch.

The winners were announced by Thomas Perlmann, secretary-general of the Nobel Committee.

Patrik Ernfors, of the Nobel Committee, said Prof Julius used capsaicin, the active component in chili peppers, to identify the nerve sensors that allow the skin to respond to heat.

Prof Patapoutian found separate pressure-sensitive sensors in cells that respond to mechanical stimulation, he said.

"This really unlocks one of the secrets of nature," said Mr Perlmann. "It's actually something that is crucial for our survival, so it's a very important and profound discovery."

Last year's prize went to three scientists who discovered the liver-ravaging hepatitis C virus, a breakthrough that led to cures for the deadly disease and tests to keep the scourge from spreading though blood banks.

The prestigious award comes with a gold medal and a prize of more than one million dollars.

The prize money comes from a bequest left by the prize's creator, Swedish inventor Alfred Nobel, who died in 1895.

The prize is the first to be awarded this year. The other prizes are for outstanding work in the fields of physics, chemistry, literature, peace and economics.