'Pain switch' could lead to a new generation of anaesthetics

Scientists claim to have found a small area of the brain in mice that can turn off their sense of pain like a light switch. US researchers say the amygdala, a small almond-shaped cluster of neurons located in each side of the brain, can turn off multiple parts of the brain that process pain. Beams of light activate a set of neurons in the amygdala, called'CeAga' neurons, which inhibit'pain-promotion centres' in the brain, they say. In experiments, activating the CeAga neurons dramatically reduced signs of discomfort in mice who had received a mild pain stimulus. While mice have a relatively large central amygdala compared to humans, it's likely humans have a similar system for controlling pain.