Neurocranium Flashcards

Study the eight neurocranial bones, cranial vault, skull base, sutures, fossae, developmental anatomy, and important clinical landmarks.

Card 1 of 30Question

What is the neurocranium?

The portion of the skull that forms the bony enclosure protecting the brain.

In This Section

1. What is the neurocranium?

The portion of the skull that forms the bony enclosure protecting the brain.

2. How many bones form the adult neurocranium?

Eight bones, consisting of four unpaired bones and two paired sets.

3. Which four neurocranial bones are unpaired?

The frontal, occipital, sphenoid, and ethmoid bones.

4. Which neurocranial bones occur as bilateral pairs?

The parietal and temporal bones.

5. What are the two major anatomical divisions of the neurocranium?

The cranial vault, or calvaria, and the cranial base.

6. What is the calvaria?

The dome-shaped superior portion of the neurocranium forming the roof and upper walls of the cranial cavity.

7. Which bones primarily form the calvaria?

The frontal, parietal, and occipital bones, with contributions from the squamous temporal bones.

8. What are the three principal layers of the cranial vault bones?

The outer table of compact bone, the diploe, and the inner table of compact bone.

9. What is the diploe?

A layer of cancellous bone between the inner and outer compact tables of the cranial vault.

10. What is the cranial base?

The inferior portion of the neurocranium that supports the brain and contains openings for nerves and vessels.

11. What are the three fossae on the internal surface of the cranial base?

The anterior, middle, and posterior cranial fossae.

12. Which cerebral lobes occupy the anterior cranial fossa?

The frontal lobes of the cerebral hemispheres.

13. Which cerebral lobes occupy the lateral portions of the middle cranial fossa?

The temporal lobes.

14. Which major brain structures occupy the posterior cranial fossa?

The cerebellum, pons, and medulla oblongata.

15. Which neurocranial bone forms the forehead and much of the anterior cranial fossa floor?

The frontal bone.

16. Which neurocranial bone contains the foramen magnum?

The occipital bone.

17. Which neurocranial bone contains the sella turcica?

The sphenoid bone, which houses the pituitary gland within its hypophyseal fossa.

18. Which neurocranial bone contains the cribriform plate?

The ethmoid bone, whose cribriform foramina transmit olfactory nerve fibers.

19. Which neurocranial bones contain the middle and inner ear structures?

The paired temporal bones, particularly their petrous portions.

20. What type of joints connect most neurocranial bones?

Fibrous joints called sutures.

21. Which suture joins the frontal bone to the parietal bones?

The coronal suture.

22. Which suture joins the two parietal bones?

The sagittal suture.

23. Which suture connects the parietal bones to the occipital bone?

The lambdoid suture.

24. What is the bregma?

The junction of the coronal and sagittal sutures.

25. What is the pterion?

The region where the frontal, parietal, temporal, and sphenoid bones meet.

26. What are fontanelles?

Membranous gaps between developing cranial bones that permit skull growth and molding during birth.

27. How do the cranial vault and much of the cranial base differ in ossification?

The vault develops mainly through intramembranous ossification, while much of the base forms through endochondral ossification.

28. Which vessels run within the diploe of the cranial vault?

Diploic veins, which communicate with intracranial and extracranial venous channels.

29. Why can a fracture near the pterion cause an epidural hematoma?

It may rupture the anterior branch of the middle meningeal artery deep to the skull.

30. What is craniosynostosis?

Premature fusion of one or more cranial sutures that can alter skull growth and shape.