Central and Cranial Nerves

Central and Cranial Nerves

1. A 40-year-old patient has a crushed lumbar spinal cord due to a fracture of the vertebral column. At what level of the vertebral column could the fracture have occurred?

• A. Lumbar vertebral column, at the level of the first lumbar vertebra.

• B. Lower lumbar vertebral column, at the level of the third and fourth lumbar vertebrae.

• C. Sacral vertebral column.

• D. Junction of the lumbar and sacral vertebral column.

Answer: A

2. A patient with an intramedullary tumor (affecting the area around the central canal) will have minimal or no impairment of which of the following sensations in the neck, trunk, and limbs?

• A. Touch.

• B. Pain.

• C. Temperature.

• D. Proprioception.

Answer: D

3. Which of the following statements regarding the spinal cord is correct?

• A. The lower end of the adult spinal cord is at the level of the upper border of the 3rd lumbar vertebra.

• B. The spinal nerves in the segments or vertebral levels of the spinal cord are of equal length.

• C. The cervical enlargement of the spinal cord lies at the level of the spinal cord segment that gives rise to the cervical spinal nerves I to IV.

• D. Lumbar puncture between the spinous processes of the lumbar vertebrae (3 and 4 or 4 and 5) will avoid puncturing the spinal nerve roots.

Answer: D

4. All the following statements about the spinal cord are correct except:

• A. The lower end of the spinal cord tapers abruptly into the conus medullaris.

• B. There is more gray matter in the cervical and lumbosacral enlargements of the spinal cord.

• C. All the spinal nerves exit the vertebral canal below the corresponding vertebral level.

• D. The anterior median fissure of the spinal cord contains the anterior spinal artery.

Answer: C

5. Which of the following statements regarding the gray matter of the spinal cord is correct?

• A. The lateral horn is present in the cervical and upper thoracic segments of the spinal cord.

• B. All the nerve fibers in the posterior root of the spinal nerve terminate in the posterior gray horn.

• C. The anterior horn contains the cell bodies of motor neurons whose axons pass to the skeletal muscles.

• D. The preganglionic parasympathetic motor neurons are located in the intermedio-lateral nucleus.

Answer: C

6. All the following statements regarding the gray matter of the spinal cord are correct except:

• A. The descending motor tracts from the brain terminate in the anterior horn.

• B. The posterior horn is the origin of the ascending sensory tracts.

• C. The gray matter of the spinal cord is surrounded by a layer of white matter which is of equal thickness throughout its length.

• D. In the cervical segment, the gray matter contains the phrenic nucleus.

Answer: C

7. All of the following statements regarding the oculomotor nerve are correct except:

• A. It contains both motor fibers for striated muscles and autonomic (parasympathetic) fibers.

• B. It passes through the superior orbital fissure to enter the orbit.

• C. It supplies the superior oblique muscle.

• D. It supplies the inferior oblique and inferior rectus muscles.

Answer: C

8. All of the following statements regarding the nerves for the extraocular muscles are correct except:

• A. The trochlear nerve has its origin from a nucleus in the midbrain.

• B. The abducent nerve nucleus lies in the pons, close to the floor of the fourth ventricle.

• C. The abducent nerve passes through the cavernous sinus.

• D. The abducent nerve exits the skull through the inferior orbital fissure.

Answer: D

9. Which of the following statements regarding cranial nerves III, IV, and VI is correct?

• A. The autonomic fibers in the cranial nerve III cause dilation of the pupil.

• B. The cranial nerve IV emerges from the brain at the level of the posterior perforated substance.

• C. The cranial nerve VI supplies the lateral rectus muscle.

• D. The cranial nerve III is unlikely to be compressed by an intracranial aneurysm.

Answer: C

10. Which of the following statements regarding the trigeminal nerve is correct?

• A. It has two roots that emerge from the anterior surface of the pons, the motor root lying outside the sensory root.

• B. The sensory fibers from the trigeminal ganglion terminate in the midbrain nuclei.

• C. The mandibular nerve is a mixed nerve.

• D. The mesencephalic nucleus of the trigeminal nerve receives only fibers from the trigeminal ganglion.

Answer: C

11. Which of the following statements regarding the ophthalmic division of the trigeminal nerve is correct?

• A. All three terminal branches of this nerve pass through the common tendinous ring of the recti muscles.

• B. The nasociliary branch, which joins the ciliary ganglion, supplies all the sensory fibers to the eyeball.

• C. The anterior ethmoidal branch of the nasociliary nerve provides sensation to the posterior part of the lateral wall of the nose and the nasal septum.

• D. The frontal branch of the ophthalmic nerve contains sensory fibers from the skin of the forehead and upper eyelid.

Answer: D

12. All of the following statements about the maxillary division of the trigeminal nerve are correct except:

• A. It gives off the superior alveolar nerves before becoming the infraorbital nerve.

• B. Its pterygopalatine branches are the route for postganglionic fibers from the pterygopalatine ganglion to the maxillary nerve.

• C. It passes through the foramen rotundum to enter the pterygopalatine fossa.

• D. The infraorbital nerve contains only sensory fibers from the face.

Answer: D

13. Which of the following statements regarding the maxillary division of the trigeminal nerve is correct?

• A. It passes through the inferior orbital fissure with the maxillary artery.

• B. It supplies sensation to the entire nasal cavity.

• C. It supplies sensation to the bridge of the nose and the upper eyelid.

• D. It is not related to the pterygopalatine ganglion.

Answer: A

14. Which of the following statements regarding the mandibular nerve is correct?

• A. It contains motor, sensory, and autonomic fibers.

• B. It passes through the foramen ovale to enter the infratemporal fossa.

• C. The trunk of the mandibular nerve lies in the upper head of the lateral pterygoid muscle.

• D. It supplies 4 muscles.

Answer: C

15. All of the following statements regarding the mandibular nerve are correct except:

• A. It usually has two branches to the temporalis muscle.

• B. The chorda tympani nerve of the facial nerve joins the lingual nerve of the mandibular nerve.

• C. The buccal nerve supplies the skin and mucosa of the cheek.

• D. It does not supply sensation to the auricle.

Answer: D

16. All of the following statements regarding the branches of the mandibular nerve are correct except:

• A. The inferior alveolar nerve contains fibers supplying the mylohyoid muscle.

• B. The mental nerve is a terminal branch of the inferior alveolar nerve.

• C. The auriculotemporal nerve accompanies the superficial temporal artery to the skin of the temporal region.

• D. The lingual nerve supplies sensation to the posterior 1/3 of the tongue.

Answer: D

17. Which of the following statements regarding the facial nerve is correct?

• A. It is the only nerve that passes through the petrous bone.

• B. It divides into terminal branches after it emerges from the parotid gland.

• C. It passes below the vestibulocochlear nerve when passing through the internal acoustic meatus.

• D. The geniculate ganglion lies at the angle between the labyrinthine and tympanic segments.

Answer: D

18. All of the following statements about the facial nerve are correct except:

• A. It contains sympathetic fibers.

• B. The sensory fibers of this nerve originate from the geniculate ganglion.

• C. It gives off the chorda tympani nerve just before it emerges from the petrous bone at the stylomastoid foramen.

• D. Within the parotid gland, it lies lateral to the posterior facial vein.

Answer: A

19. Which of the following statements regarding the branches of the facial nerve is correct?

• A. The greater petrosal nerve contains sensory fibers from the tongue.

• B. The chorda tympani nerve contains autonomic fibers that go to the submandibular ganglion.

• C. The branch to the stapedius muscle is given off at the level of the geniculate ganglion.

• D. The posterior auricular branch supplies the occipitalis muscle.

Answer: B

20. Which of the following statements regarding the facial nerve is correct?

• A. The geniculate ganglion contains the cell bodies of sensory neurons.

• B. The motor fibers travel directly from the facial nerve motor nucleus to the pontocerebellar sulcus.

• C. The facial nerve crosses the midline in the presigmoid recess before entering the parotid gland.

• D. The autonomic fibers of the facial nerve originate from the inferior salivatory nucleus.

Answer: A

21. Which of the following statements regarding the vestibulocochlear nerve is correct?

• A. It passes within the facial nerve canal along with the facial nerve.

• B. The peripheral processes of the vestibular ganglion neurons branch to the saccule, utricle, and ampullae of the semicircular canals.

• C. The vestibular ganglion lies at the outer end of the external acoustic meatus.

• D. The vestibular nerve nuclei are not located in the medulla oblongata.

Answer: A

22. All of the following statements regarding the vestibulocochlear nerve are correct except:

• A. A tumor of the vestibulocochlear nerve may compress the facial nerve.

• B. Within the internal acoustic meatus, the cochlear nerve lies below the facial nerve.

• C. The vestibulocochlear nerve enters the brain at the pontomedullary sulcus.

• D. The cochlear nerve fibers terminate in the solitary nucleus.

Answer: D

23. All of the following statements about the glossopharyngeal nerve are correct except:

• A. The sensory fibers in this nerve terminate in the solitary nucleus and the spinal nucleus of the trigeminal nerve.

• B. It is the sensory nerve for the pharynx, posterior 1/3 of the tongue, tympanic cavity, carotid sinus, and carotid body.

• C. Its auricular branch contains sensory fibers.

• D. It supplies the stylopharyngeal muscle.

Answer: C

24. Which of the following statements regarding the glossopharyngeal nerve is correct?

• A. Its sensory fibers do not terminate in the solitary nucleus.

• B. Its motor fibers supply the digastric muscle.

• C. Its autonomic fibers originate from the inferior salivatory nucleus.

• D. It emerges from the brain at the anterior median sulcus.

Answer: C

25. Which of the following statements regarding the vagus nerve is correct?

• A. The dorsal motor nucleus (posterior nucleus) of the vagus nerve is the origin of the motor fibers for the muscles of the palate and pharynx.

• B. The superior and inferior ganglia are swellings on the course of the vagus nerve that contain cell bodies of sensory neurons.

• C. The superior laryngeal branch of the vagus nerve supplies most of the muscles of the larynx.

• D. The vagus nerve passes through the posterior part of the jugular foramen.

Answer: B

26. All of the following statements regarding the branches of the vagus nerve are correct except:

• A. The pharyngeal branch of the vagus nerve contains motor fibers to the muscles of the palate and pharynx.

• B. The vagus nerve gives off branches that supply the heart.

• C. The recurrent laryngeal branch supplies the muscles of the larynx.

• D. The terminal branches of the vagus nerve supply the pelvic viscera.

Answer: D

27. All of the following statements regarding the relationships of the vagus nerve are correct except:

• A. The left vagus nerve does not cross the left subclavian artery.

• B. The right recurrent laryngeal nerve is longer than the left recurrent laryngeal nerve.

• C. The vagus nerve descends in the neck along the internal carotid and common carotid arteries.

• D. The vagus nerves lie posterior to the hilum of the lungs.

Answer: B

28. All of the following statements about the accessory nerve are correct except:

• A. The accessory nerve is the most inferior of the three nerves that emerge from the posterior median sulcus.

• B. The cranial root of the accessory nerve passes through the foramen magnum to unite with the spinal root.

• C. The fibers in the cranial root of the accessory nerve originate from the nucleus ambiguus.

• D. The accessory nerve passes through the posterior triangle of the neck.

Answer: B

29. Which of the following statements regarding the cranial nerve XII is correct?

• A. The cranial nerve XII emerges from the brain at the posterior median sulcus.

• B. The cranial nerve XII exits the skull through the foramen magnum.

• C. Those fibers of the cranial nerve XII that originate from cervical nerve I do not pass through the hypoglossal canal.

• D. The cranial nerve XII gives off a root from the inferior loop of the ansa cervicalis.

Answer: C

30. Which of the following statements regarding the external surface of the medulla oblongata is correct?

• A. The groove between the pyramids becomes indistinct at the level of the pyramidal decussation.

• B. The roots of the hypoglossal nerve emerge from the posterior median sulcus.

• C. The inferior olivary nucleus lies on either side of the posterior median sulcus.

• D. The superior medullary velum lies on the surface of the medulla oblongata.

Answer: A

31. All of the following statements regarding the medulla oblongata are correct except:

• A. The medulla oblongata contains the relay station between the first and second order neurons of the conscious proprioceptive pathway of the neck, trunk, and limbs.

• B. All ascending sensory tracts from the spinal cord are present in the medulla oblongata.

• C. The medulla oblongata contains centers that regulate essential functions of the body.

• D. The nucleus ambiguus lies inferior to the area postrema.

Answer: D

32. All of the following statements regarding the pons are correct except:

• A. The pontine tegmentum contains the pontine nuclei.

• B. The corticospinal tracts pass through the pontine tegmentum.

• C. The pons contains the relay station for the cerebello-cerebral pathway.

• D. The abducent nerve nucleus lies in the pontine tegmentum.

Answer: D

33. Which of the following statements regarding the pons is correct?

• A. The pons contains the terminal nuclei for the cochlear nerve fibers.

• B. All the sensory fibers of the cranial nerve V terminate in nuclei in the pons.

• C. The motor nucleus of the facial nerve lies in the pontine tegmentum.

• D. The falx cerebri lies in the pontine tegmentum.

Answer: A

34. All of the following statements regarding the midbrain are correct except:

• A. The superior colliculus is the center for reflexes related to vision.

• B. The inferior colliculus is part of the auditory pathway.

• C. The descending and ascending tracts in the midbrain are separated by the red nucleus.

• D. The falx cerebri lies posterior to the substantia nigra, lateral to the red nucleus.

Answer: C

35. All of the following statements regarding the temporal lobe are correct except:

• A. There is no sulcus that separates the temporal lobe from the occipital lobe.

• B. It is contiguous with all the other four lobes of the brain.

• C. It lies on all three surfaces of the cerebral hemisphere.

• D. It contains one of the horns of the lateral ventricle.

Answer: C

36. Which of the following statements regarding the frontal lobe is correct?

• A. It is separated from the cingulate gyrus by the parieto-occipital sulcus.

• B. The sensory area for the body lies in the frontal lobe.

• C. It lies immediately anterior to the postcentral gyrus of the parietal lobe.

• D. Its inferior surface lies on the middle cranial fossa.

Answer: B

37. All of the following statements about the parietal lobe are correct except:

• A. It does not lie on the inferior surface of the hemisphere.

• B. It lies on the superolateral and medial surfaces of the cerebral hemisphere.

• C. It is contiguous with the frontal, occipital, temporal, and limbic lobes.

• D. On its superolateral surface, it is bounded by the postcentral sulcus, parieto-occipital sulcus, and lateral sulcus.

Answer: D

38. Which of the following statements regarding the limbic lobe is correct?

• A. It lies on all three surfaces of the hemisphere.

• B. It consists of three parts: The hippocampus, the cingulate gyrus, and the subcallosal area.

• C. It is bounded by the cingulate, parieto-occipital, and subparietal sulci.

• D. It is vulnerable to injury if there is a depressed fracture of the cranial vault.

Answer: C

39. A patient presents with complete loss of sensation and motor function on the right half of his body due to a cerebral infarction. The most likely artery involved in the following list is:

• A. Left anterior cerebral artery.

• B. Cortical branch of the left middle cerebral artery.

• C. Lenticulostriate branches of the left middle cerebral artery.

• D. Left posterior cerebral artery.

Answer: C

40. Regarding the medulla oblongata:

• A. It is the relay station for the conscious proprioceptive pathway.

• B. It is the site of decussation of most of the corticospinal fibers.

• C. It only contains nuclei of cranial nerves IX to XII.

• D. It contains the auditory and visual centers.

Answer: D

41. Regarding the pons:

• A. It contains the principal sensory nuclei of the cranial nerve V.

• B. It contains nuclei that give rise to axons to the cerebellum.

• C. The motor nucleus of the facial nerve is not located in the pons.

• D. The vestibular nerve nuclei are located in both the pons and medulla oblongata.

Answer: D

42. Regarding the midbrain:

• A. The midbrain does not contain any nuclei of the cranial nerve V.

• B. The substantia nigra separates the motor tracts and sensory tracts in the midbrain.

• C. The nucleus of the cranial nerve III lies in a transverse section through the superior colliculus.

• D. The red nucleus lies anterior to the substantia nigra.

Answer: C

43. Regarding the gray matter of the spinal cord:

• A. The posterior gray horn is the termination of all fibers in the posterior root of the spinal nerve.

• B. Axons in the posterior funiculus of the spinal cord do not originate from the posterior gray horn.

• C. The anterior gray horn is the origin of a small part of the fibers in the anterior root of the spinal nerve.

• D. Axons from the intermedio-lateral nucleus (of the lateral horn) travel to all sympathetic and parasympathetic ganglia in the periphery.

Answer: B

44. Regarding the white matter of the spinal cord:

• A. The anterior funiculus in the two halves of the spinal cord are connected through the anterior white commissure.

• B. The sensory tracts increase in size from below upwards.

• C. The descending motor tracts to the spinal cord all originate from the cerebrum.

• D. All sensory fibers from the posterior gray horn that ascend to the brain decussate before ascending.

Answer: D

45. Regarding the spinal cord:

• A. The spinal cord supplies all the skeletal muscles of the body.

• B. The parasympathetic nuclei of the spinal cord supply all the viscera in the thorax and abdomen.

• C. The central canal of the spinal cord continues for a short distance into the lower medulla oblongata before it communicates with the fourth ventricle.

• D. The lateral horn of the gray matter of the spinal cord is present throughout the entire length of the spinal cord.

Answer: C