Dr Guy S Bewick studies the neuromuscular system to understand how nerve terminals produce such amazingly diverse functions. This involved developing a new technique for optically monitoring living nerve terminal function (with Prof Bill Betz, Colorado, USA), subsequently adopted worldwide. This led to a collaboration with Dr Bob Banks (Durham University) to understand position-sensing (proprioceptive) nerve terminals in muscle and their components. This uncovered the surprising finding that these proprioceptive endings secrete a chemical when they move, a secretion that is essential for their sensory function. With Prof Chih-Cheng Chen (Academia Sinica, Taiwan), we discovered this secretion can interact with nearby pain fibres, priming and triggering chronic pain in a fibromyalgia model. We are now exploring whether these new molecular and neural pathways explain the resistance of fibromyalgia-like chronic pain to current treatments and may offer new therapeutic targets for pain relief.