For a long time, the scientific consensus was clear: you are born with a fixed number of neurons, and once they are gone, they are gone. The brain, we were told, was essentially hardwired by adulthood with little capacity for change. The good news, backed by decades of growing research, is that this is no longer the whole story. As physiotherapists, this science matters deeply to us, because understanding how the brain adapts and regenerates changes the way we approach pain,