The invention of realistic portraiture to reveal "inner life" is attributed by some art historians to Jan van Eyck who worked in Flanders from 1420 onwards. We show, using clinical neurological examination of the gold mask of Agamemnon dating from 1550-1500 BC and of the portraits of Henry III and his son Edward I -- important English royals -- painted between 1216 and 1307, that realistic portraits were made well before the 15th Century. Thus artists unwittingly used neurology as part of their realistic approach to the presentation of the face. Because neurological diagnosis is often visual, neurology, in turn, has a rich potential to unveil examples of realism in art. We consider the art pieces examined here also pertinent to art historians, as they assess the role of art in documenting history.