Abstract: This study discusses some of the central issues in the design and interpretation of Electroencephalograms (EEGs), Fast Fourier Transforms (FFTs), Visual Evoked Potentials (Visual EPs), Auditory Evoked Potentials (Auditory EPs) and Auditory P300 Event-Related Potentials (Auditory P300 ERPs) tests. Many design and interpretation issues are unique to a given content area but many principles apply to virtually all EEGs, EPs and ERPs studies and these common principles are the focus of this study. The study begins with a discussion of the file numbering system for all topographic brain mapping tests assigned by the Brain Atlas III (BA-III). It then discusses the principles of design and interpretation. Throughout the study, the most significant points are distilled into a set of paradigms for designing and interpreting EEGs, FFTs, EPs and ERPs tests.