Those involved in research or clinical work related to brain function will be used to the dinner party question “we only use 50% of the brain, don't we?” The scientist's dismissive sneer is usually well enough concealed, depending on how much he or she has had to drink. Where on earth did this lay myth arise, we chuckle over coffee in the common room on Monday morning? But scientists and clinicians are not immune to myths also. For many decades, neuroscientists preached the doctrine that the adult brain is ‘hard-wired’. Perhaps in very early childhood, we conceded, plastic changes in the brain were possible, but after the age of three or four years connections were indelibly made.