Silver Book Fact
The ability to recognize faces declines with age and requires, on average, being 5 feet closer to the face with every decade after the age of 60.
Lott L, Haegerstrom-Portnoy G, Schneck M, Brabryn J. Face Recognition in the Elderly. Optometry and Vision Science. 2005; 82(10): 874-81. http://www.optvissci.com/pt/re/ovs/abstract.00006324-200510000-00007.htm;jsessionid=GqnW6wB90JgVG34j51XQ2JLvw9fcB89PJhH3TShgPrfwgqLgs7ps!-1754492629!181195629!8091!-1