Newly discovered networks of synapses, or junctions between cells, may be responsible for transmitting chronic pain. These silent synapses not normally used provide an alternative network of cell junctions for pain transmission to the brain. Their existence was suggested over 20 years ago but until last year had not been investigated in any detail.
The study, published in, was a collaboration including Dr Zhuo and colleagues from Washington University School of Medicine, Howard Hughes Medical Institute, Massachusetts General Hospital and Harvard Medical School. They discovered that once the synapses were awakened they remained active and relayed painful sensory information to the brain even after the pain stimulus was gone. Most known medications have little or no effect on chronic pain signals sent through this network.