Analyzing ocular-motor control dysfunction: insights into disease processes and normal function

The author examines several ways in which the application of engineering analysis tools have contributed to one´s understanding of both dysfunction (e.g., eye movements provoked by disease) and normal function of the ocular motor system. In the past 30 years, beginning with the work of Gerald Westheimer, Larry Stark, Laurence Young and David Robinson, there have been scores of studies of ocular motility that were firmly based on engineering principles and carried out using a classic control-systems approach. The author limits the discussion to concentrating on only a few such studies that have eliminated from the author´s own laboratory. Specifically, the author focuses on studies into two eye-movement disorders: gaze-evoked nystagmus and congenital nystagmus. These studies were conducted on humans with one or the other of these conditions and had the dual aims of: 1) understanding the mechanisms underlying the pathological eye movements; and 2) using the findings to infer how the normal ocular motor system is organized