Hope has been raised for a new way of treating pain after scientists successfully ‘silenced’ the brain cells that interpret discomfort. Exposing mice to unpleasant temperatures or skin pricks activates an area of their brains known as the amygdala, which processes emotions. When cells in the amygdalas of the rodents were blocked, the animals still produced pain signals but they were not interpreted by their brains. This caused the rodents to move away from the source of pain but show no sign of distress, such as licking their wounds, scientists said. ‘It’s as if they don’t care about pain any more, even though they can detect it,’ said lead author Professor Grégory Scherrer at Stanford University. To investigate how the brain interprets pain, the researchers genetically-modified cells in the amygdala of mice so they became fluorescent when active. They found these cells lit up when the mice were exposed to heat or a small pin prick, New Scientist reported. To silence these cells, the scientists genetically engineered them to express receptors for an unnamed drug that dampened their activity. Brain circuits for pain tend to be similar between species, with these mechanisms likely also occurring in humans. This gives the researchers hope their findings could lead to ‘novel therapeutic strategies’ that minimise ongoing discomfort. ‘We’re hoping it’s a new avenue to treat pain,’ Professor Scherrer said. The findings were published in the journal Science. The discovery follows previous research that found damage to the amygdala reduces the sensation of pain. However, it is important people and animals know to move away from the source of discomfort as it could cause damage. Pain signals therefore still need to be produced, but not interpreted by the brain, the scientists warned. Fifty million adults in the US – 20.4 per cent of adults – suffer from chronic pain, according to a report by the Centers for Disease Control and Prevention. The report defines chronic pain as occurring every day or most days for at least six months. In the UK, 28million adults – two fifths of the population – are living with pain that has lasted at least three months, British Pain Society data reveals. Common causes include headache, abdominal cramps, muscle strain and arthritis. Published in Daily Times, January 21st 2019.