In the 1920s, Gerstmann described a set of problems found in people who have suffered damage to the brain's left parietal lobe, problems that include being unable to understand arithmetic and having difficulty identifying one's fingers. There is still no agreement on whether the symptoms Gerstmann noticed constitute a syndrome, but the parts of the brain used for storing facts about numbers and for representing the fingers are close to each other. Mental representations of numbers and of fingers may therefore be functionally connected. A 2005 experiment had people perform some tasks requiring dexterity and others involving matching pairs of numbers, while an area of their parietal lobes – the left angular gyrus – was stimulated by a magnetic field. Facility at both sets of tasks was impaired.