The algorithm evaluates multiple morphological features to find the best-matching atlas plate:
- Ventricle geometry — lateral ventricle shape changes dramatically along the AP axis
- Hippocampal formation — the presence, size, and curvature of hippocampal layers
- Cortical features — thickness and layering patterns vary by AP level
- Subcortical nuclei — the appearance of thalamic, hypothalamic, and striatal structures