The Changing Visual System

In late May and early June 1991, a NATO Advanced Study Institute was held at a hotel in the hilltop village of San Martino al Cimino a few kilometers from the city of Viterbo in the Lazio region of Italy. The title of the course was the same as this volume and brought together specialists working at all phases of the life span (embryology, infancy, childhood, middle life and senescence) in both animals and humans to exchange ideas, facts and theories in the search for common principles. Such pri