Anterior, middle and posterior cranial fossa
- The cranial base is divided into anterior, middle, and posterior cranial fossae by two laterally running ridges (lesser wing of sphenoid, frontak bone and dorsum sellae of sphenoid, and pyramis of petrous part of temporal bone). These become lower in a staircase-like pattern as one moves from anterior to posterior. Each cranial fossa is a depression that contains the lower half of the brain.
- The anterior fossa contains the frontal lobe of the cerebrum, the middle fossa the temporal lobe, and the posterior fossa the cerebellum, pons, and medulla oblongata.