1. A method of overlaying Navigated Brain Stimulation (NBS) functional data on a live image of a brain, said method comprising the steps of; obtaining a live image of a brain, obtaining a functional map of the brain comprising an anatomical model of the brain and NBS functional data associated with the brain, identifying at least one anatomical landmark of the brain from the live image of the brain, identifying at least one of said identified anatomical landmarks on the anatomical model of the brain, modifying the functional map so that the identified at least one anatomical landmark of the model corresponds in size and orientation to the corresponding at least one anatomical landmark in the live image of the brain, and digitally overlaying at least said NBS functional data on said live image of the brain according to the corresponding, aligned anatomical landmarks.