The Human Eye: Structure and Function

Understanding the eye requires an exploration of the relationship between its structure and its function--that is, a consideration not only of how the eye and its parts are constructed, but also of what they do and how they work. Thus this book considers both the structure and the function of the human eye and how they are related, often using functional issues as a guide to the most meaningful and important features of the anatomy. Limited use of technical terms from the various disciplines that relate to the eye, definitions of terms as they are used, a glossary, and suggestions for additional reading are all included to make the text accessible to readers for whom the subject is new. Boxes interspersed throughout the text discuss methods used to study the structure of the eye and surgical procedures used to alter its structure in beneficial ways. In addition to the main theme of structure and function, several subthemes make the general point, in different ways, that the eye and our understanding of it are dynamic and changing. Change on a geological timescale is represented by the evolutionary history of eyes generally and the human eye's place among the diversity of eyes in the animal kingdom; these issues are discussed in the Prologue. Change within a human lifetime begins with a chapter about the early stages of development in utero, continues throughout the book with the developmental histories of different parts of the eye, and concludes, in the Epilogue, with accounts of postnatal growth, maturation, and senescence. Change throughout human history in the way we have understood our eyes is another story, fragments of which are contained in a series of "vignettes" about some of the people and ideas that have influenced human thought about the eye over the past several thousand years.