We describe the details and application of a digital brain atlas for the comparison and integration of graphical neurobiological data. The atlas consists of multiple sets of high-resolution video images acquired from histological tissue sections representing a 3-dimensional (3D) volume of an exemplar rat brain. Through an interactive graphical interface running on a standard computer workstation, experimental data is brought into register with the atlas. Once in the atlas, coordinate reference frame data can be compared, analyzed, and visualized in 3 dimensions. We demonstrate the aridity and usefulness of the digital brain atlas with a series of results on the visceral neuraxis in the rat.