Using a personal computer as a tool, methods of studying the time course and sequencing of human brain processes are described. Reasons are given for choosing the visual system and brain control of eye movement as the input-output model for tracing the processes. With such a model it is possible to study the spectrum of functions from initial input processes to higher level controls often attributed to the prefrontal cortex. The testing technique was devised for use in relation to a unified theory of brain processing but it is a useful approach to functional assessment regardless of the particular theory being evaluated.