Stereotaxic coordinates define positions in the brain along three axes:
- Anterior-Posterior (AP) — measured from Bregma, positive values anterior (toward the nose), negative values posterior (toward the cerebellum)
- Medial-Lateral (ML) — measured from the midline, always positive, increasing toward the ears
- Dorsal-Ventral (DV) — measured from the brain surface or skull, increasing in depth
A coordinate like AP -2.0, ML 1.5, DV 1.2 precisely identifies a point in the hippocampus.