Abstract
Inaccurate accommodation in children with Down syndrome (DS) has been reported by our and other groups for some years, but we are still a long way from understanding what causes the deficit. About three quarters of children with DS consistently under-accommodate and, curiously, the deficit persists when hypermetropia is corrected. Bifocals are successful in improving the accommodative response and rendering near work in focus. Recently, we have shown that 40% of children who wear bifocals ultimately ‘learn’ to use their own accommodation accurately and are able to dispense with the bifocals. This finding suggests that it is not the case that children with DS can't accommodate accurately, but that they don't. The challenge is, therefore, to determine what allows some children to develop accurate accommodation spontaneously, and what feature of bifocals allows others to develop it later.