Time activity curve. Talairach space A widely accepted standard coordinate system of brain physiologically based regions, that is, an atlas space, to which an individual brain geometry from a scan can be transformed and realigned for purposes of matching corresponding regions among brains. Each point in the individual brain is given Talairach coordinates, (x, y, z) for its location in Talairach space. With the wide variations in individual brain size, shape, and structure, being able to transform region locations into a standard template facilitates comparisons of scans among individuals. See also Broadmann’s area.