Coordinate systems
Subject Coordinate System (SCS)
Definition
How to position the points
Nasion (NAS)
Left pre-auricular point (LPA)
Right pre-auricular point (RPA)
Talaraich coordinate system
Definition
How to position the points
Anterior comissure (AC)
Description of the anterior commissure at this Wikipedia page.
Technique to localize it: use
Posterior commissure (PC)
Description of the posterioe commissure at this Wikipedia page.