The visual evoked potential (VEP) is used to assess visual performance in a wide variety of animals. A recent literature search found that in the last 25 years, VEPs were recorded from mice,^{35,44,61,67,85,89,97,121} rats,^{9,33,36,68,72,87,94,137} guinea pigs,^118,119 turtles,⁷⁹ fish,¹² birds,⁸⁸ rabbits,^81,82 cats,^84,86,215 dogs,^4,113,132 swine,¹³⁴ sheep,^16,111 cows,^112,120 monkeys,^10,133,138 baboons,¹⁰⁷ and great apes.¹¹ A small subset of the references is listed for each species. The specific species chosen for investigation was based on the experimental question asked and the availability of the species. For example, rats are a readily accessible lab animal with a short growth cycle and were used extensively to study the effects of drugs on the visual system. Because of this, the most common species employed in VEP studies was the rat. Monkeys, the second most common species investigated with VEPs, was studied because of its close anatomical relationship to humans. Thus, the VEP has been investigated in many different species for many different reasons.

Because of the extensive literature on VEPs in animals, this chapter will focus on only two species: mice and monkeys. The monkey literature will be reviewed because it reveals important information concerning the recording of VEPs in humans. The origin of the individual VEP components under various stimulus conditions has been investigated in monkeys. The mouse has recently become the model for many different retinal diseases. The reasons for this are many. For example, the mouse has a short life span, so the course of a disease can be followed in a relatively short time. Furthermore, mice can be bred with different retinal diseases, and treatments for these retinal diseases can be perfected in these mice models. The visual evoked potential has the potential to be employed to follow the course and treatment of diseases that affect the visual system. Thus, these two species appear to be the most pertinent to the understanding of the visual system of the human.