Abstract
Visual evoked potentials (VEPs) are useful for investigating the physiology and pathophysiology of the human visual system, including visual pathways and the visual cortex. The most commonly used method is pattern reversal (PR) stimulation using either a checkerboard pattern or a grating pattern. Identification of generator sources of VEPs may improve their clinical utility. Since magnetoencephalography has several advantages over electric fields in localizing cortical potentials, there have been a number of studies regarding neural generators of visual evoked magnetic fields (VEFs). In the present study, we have reviewed VEF studies to search for the possible standardization of stimulus parameters for clinical application of VEFs. Only nine papers were met our criteria. Most VEF studies have been focusing on the source localization during the visual tasks to relate the visual function with known physiology and anatomy. In such tasks, neural generators of PR-VEPs have been elucidated. However, stimulus parameters such as check size and size of visual field were varied among the studies. Therefore, one must be cautious when interpreting the results of previous VEF studies. We have commented on the possible problems of the previous studies in terms of the visual physiology.
