Transient visually evoked potential.

A light delivered to the human eye will instigate changes in electrical potentials recorded over the visual cortex that last for some finite time, at least several hundred milliseconds. If the rate of stimulation is sufficiently low, the response is completed before the next visual stimulus arrives; the cortical potential is then called a transient evoked response. This review of the transient evoked potential describes the techniques by which the response is obtained, the problems inherent in its use, and procedures by which these difficulties can be overcome or minimized. A summary of the research results from the field enumerates those findings which have been well established and replicated by many investigators, those that are more controversial or as yet inconclusive, and the many practical applications of the technique for science and medicine. Finally, the needs for an underlying physiological theory and for future research are discussed.