*** ----> Scientists shed light on how brains turn pain up or down | THE DAILY TRIBUNE | KINGDOM OF BAHRAIN

Scientists shed light on how brains turn pain up or down

Pain perception is essential for survival, but how much something hurts can sometimes be amplified or suppressed: for example, soldiers who sustain an injury in battle often recall not feeling anything at the time.

A new study published in Cell Reports on Tuesday honed in on the brain circuitry responsible for upgrading or downgrading these pain signals, likening the mechanism to how a home thermostat controls room temperature. Yarimar Carrasquillo, the paper’s senior author and a scientist for the National Center for Complementary and Integrative Health (NCCIH), said the region responsible was the central amygdala, which according to her work appeared to play a dual role.

Studying mice, Carrasquillo and her colleagues found that the activity in neurons that express protein kinase C-delta amplified pain, while neurons that express somatostatin inhibited the chain of activity in the nerves required to communicate pain. The central amygdala isn’t completely responsible for pain itself: if it were removed entirely, then “the ‘ouch’ of things, or the protective pain, would remain intact,” said Carrasquillo.