With this hypothesis in mind, she reckoned that another way to treat phantom-limb pain might be to prevent pain memories from forming in the first place.

Some amputees are already known to experience phantom limb pain - a feeling of pain in a limb that is no longer there - but synaesthetic pain is different.

All of these results suggest to Dr Flor that phantom-limb pain is best understood as a form of unconscious learning, similar to motor reflexes and perception skills.