Material Covered: Gross Brain and Spinal Cord, Spinal Cord Tracts, Medulla,
Pons and Midbrain

Use the following letters to indicate your answer:

A: Only I is true
B: Only II is true
C: Both are true
D: Both are false

1.      I. Part of cranial nerve 6 and all of cranial nerve 4 are contained
            in the middle cranial fossa.

         II. The lesser wing of the sphenoid bone is a boundary between
            the anterior and middle cranial fossa.
 

2.      I. The great vein of Galen leads directly into the straight sinus.

         II. The superior petrosal sinus drains the cavernous sinus.
 

3.      I. Lamina terminalis forms the rostral wall of the 4th ventricle.

        II.  The anterior free edge of the tentorium forms the incisure.
 

4.      I. Herniation of the uncus of the cerebellum can cause pressure on
            the reticular formation, thereby inducing coma.

         II. Cranial nerves 3, 4 and ophthalmic and maxillary division of the
            trigeminal nerve can be found on the lateral wall of the cavernous sinus.
 

5.      I. The anterior communicating artery connects the anterior cerebral artery
            to the middle cerebral artery, forming part of the circle of Willis.

         II. The posterior inferior cerebellar artery (PICA) branches off the basilar
            artery.
 

6.      I.  The lateral striate arteries branch off the posterior cerebral artery to
            supply the basal ganglia with blood.

         II. Both cranial nerves 8 and 9 egress from the cranial vault through the
            jugular foramen.
 

7.      I. The inferior anastomotic vein connects with the transverse sinus.

         II. The thalamostriate vein connects with the internal cerebral vein to
            form the venous angle, a radiological landmark for the cerebral aqueduct.
 

8.      I. Bridging veins traverse the skull, connecting veins from the scalp to the
            superior sagittal sinus.

         II. The internal cerebral vein can be found in the 3rd ventricle.
 

9.      I. Choroid plexus, which produces CSF, can be found in the 3rd and 4th
            ventricles as well as the inferior horn of the lateral ventricle.

         II. The interpeduncular cistern is posterior to the midbrain.
 

10.     I.  The ambient cistern can be found lateral to the midbrain.

         II. The C6 cervical nerve root leaves the vertebral column caudal to
            cervical vertebra 5.
 

11.    I.  The artery of Adamkiewicz usually enters the vertebral column at
            T11 or T12 and supplies the lumbar-sacral enlargement with blood.

         II. The vertebral arteries arise from the thyrocervical trunk.
 

12.    I. Posterior spinal arteries supply blood to the dorsal funiculus.

         II. Damage to the lumbar vertebra L5 would probably result in
            damage to the conus medullaris.
 

13.    I. Dorsal nucleus of Clark is involved in reflex proprioception and can
            be found at levels C8-L2.

         II. The neurons whose axons create the phrenic nerve can be found at C3-C5.
 

14.    I. Internuncial neurons within the spinal cord can communicate with other
            neurons in spinal cord segments rostral and caudal via the fasciculus proprius
            tract.

         II. The C8 dermatome field sends sensory fibers only to the C8 spinal cord segment.
 

15.    I. The lateral spinothalamic tract carries sensory information from the ipsilateral
            side of the body.

         II. The nucleus proprius receives afferents from pain and temperature receptors.
 

16.    I. General tactile, i.e., crude touch, sends efferent fibers to the reticular formation.

         II. Axons from the dorsal root ganglion, conveying pain and temperature,
            traverse 1 or 2 spinal cord levels.
 

17.     I. Fasciculus cuneatus conveys fine touch from spinal cord levels T12 and rostral.

         II. Conscious proprioception from the right side of the body is conveyed to both
            the right and left brain.
 

18.     I. Neurons from the Raphe nucleus project to the dorsal horn of the gray matter
            and use serotonin (5HT) as their neurotransmitter to effect pain modulation.

         II. The postcentral gyrus is the region of the cortex that is involved with sensory input.
 

19.     I.  All corticospinal axons cross at the level of motor decussation.

         II. Hyperreflexia and fasciculations are symptoms of an upper motor neuron lesion.
 
 

20.    I. The dorsal spinocerebellar tracts carry conscious proprioception signals from
            the ipsilateral side of the body, while the ventral spinocerebellar tracts serve
            the contralateral side of the body.

         II. Cuneocerebellar fibers enter the cerebellum through the middle cerebellar peduncle.
 

21.    I. The inferior cerebellar peduncle can be seen at the medulla, pons and midbrain levels.

         II. The rhomboid fossa forms the anterior wall of the 4th ventricle.
 

22.     I. Infants have a positive Babinski sign because not all of the axons of the corticospinal
            tract have reached the lower motor neurons.

         II. Precentral gyrus is one of the motor areas of the brain.
 

23.     I. The hypoglossal nuclei are visible at the level of sensory decussation and level of
            motor decussation.

         II. Vestibuli nuclei can be found at the level of the vagus nerve.
 

24.    I. The 3 nuclei of the vagus nerve are the nucleus solitarius, nucleus ambiguus and
            dorsal motor nucleus.

         II. The 3 nuclei of the glossopharyngeal nerve are the nucleus ambiguus, superior
            salivatory nucleus and nucleus solitarius.
 

25.     I. The pyramids at the level of the vagus nerve carry corticospinal fibers, i.e., pyramidal tracts,
            which innervate the contra side of the body.

         II. The medial lemniscus at the level of the vagus nerve carries pain and temperature
            sensation from the contralateral side of the body.
 

26.    I. The medial longitudinal fasciculi at the level of the vagus nerve are anterior (ventral)
            to the hypoglossal nuclei.

         II. The hypoglossal nerves egress from the brain stem lateral to the olivary nucleus.
 

27.    I. The widest part of the fourth ventricle is at the level of the vestibulocochlear/glossopharyngeal nerves.

         II. The vagus and accessory nerves egress from the cranial vault via the jugular foramen.
 

28.    I. If the patient’s tongue deviates to the right when asked to protrude it, the patient may
            have a right lower motor lesion of the hypoglossal nerve.

         II. The dorsal motor nucleus of the vagus nerve sends out visceral efferent fibers.
 

29.    I. The otic ganglion has pseudounipolar sensory neurons that carry sensory information
            from the oral and nasal pharynx as well as from the carotid sinus and carotid body.

         II. Parasympathetic innervation of the heart is mediated through the dorsal motor nucleus
            of the vagus nerve.
 

30.     I. In the gag reflex the vagus nerve conveys the sensory input and the glossopharyngeal
            nerve effects the muscular movement of the upper pharynx.

         II. The anterior spinal artery is a major vascular source for the lateral vascular zone of the medulla.
 

31.     I. An occlusion of the posterior inferior cerebellar artery would probably affect all three
            nuclei of the vagus nerve.

         II. The inferior salivatory nuclei send efferent fibers to the otic ganglion.
 

32.    I. The smooth muscles of the GI tract are under the influence of the dorsal motor nucleus
            of the vagus nerve.

         II. The inferior ganglion of the glossopharyngeal nerve conveys visceral sensory information
            from the carotid sinus.
 

33.    I. The hypoglossal nerve runs through both the posterior and middle cranial fossa.

         II. The medial longitudinal fasciculus carries internucial fibers.
 

34.    I. The spinothalamic tracts found at the level of the vagus nerve carry pain/temperature
            and general tactile sensation from the contralateral side of the body.

         II. The lateral cuneate nucleus receives input from axons conveying fine touch for the upper body.
 

35.    I. A complete ablation of the medial lemniscus in the pons at the level of the abducens and
            facial nerve root level would result in an internal strabismus.

         II. The ventral spinocerebellar tracts found at the level of the pons carry reflex proprioception
            from the contralateral side of the body.
 

36.    I. The inferior salivatory nucleus of the facial nerve sends efferent axons to the pterygopalatine
            ganglion.

         II. Pontocerebellar fibers project to the cerebellum via the inferior cerebellar peduncle.
 

37.    I. The mesencephalic nucleus, spinal nucleus, motor nucleus and chief sensory nucleus are
            nuclei of trigeminal nerve.

         II. The locus ceruleus is considered part of the reticular formation.
 
 

38.    I. Axons connecting the motor cortex to the reticular formation can be found in the lateral
            lemniscus.

         II. The paramedian pontine reticular formation is involved with sleep/wake cycles.
 

39.    I. Sensory neurons for taste can be found in the submandibular ganglion.

         II. The trigeminal nerve innervates the stapedius muscle.
 

40.    I. Ablation of the right oculomotor nuclei will lead to an external strabismus of the left eye.

         II. The superior cerebellar peduncle carries cerebellar efferents to the contralateral red nucleus.
 

41.    I. The mesencephalic nucleus is unique in that it is the only sensory nucleus
            (i.e., within the CNS) that has primary sensory neurons in it.

         II. The maxillary branch of the trigeminal nerve egresses from the cranial vault
            via the foramen ovale.
 

42.    I. General tactile modality in the face is conveyed by the trigeminal nerve and those
            sensory neurons, which are in the trigeminal ganglia, synapse on the rostral region
            of the spinal trigeminal nucleus.

         II. The ventral trigeminothalamic tracts carry pain and temperature from the contralateral
            side of the face.
 

43.    I. Fine tactile information from the right side of the face is conveyed bilaterally to thalamus
            and then on to the left and right precentral gyri.

         II. A lower motor neuron lesion of the facial nerve will lead to paralysis only to the ipsilateral
            lower quadrant of the face.
 

44.    I. The lingual nerve carries fibers for both the trigeminal and facial nerves.

         II. A lesion of the facial nerve at the stylomastoid foramen will result in ipsilateral  facial
            paralysis and loss of taste to the anterior 2/3 of the tongue.
 

45.    I. The right trochlear nucleus innervates a right eye muscle.

         II. Decussation of the superior cerebellar peduncle is found at the level of the superior
            colliculus.
 

46.    I. The inferior colliculus is involved in visual reflexes.

         II. The trochlear nerve runs through the red nucleus.
 

47.    I. Parkinson’s disease causes resting tremors because of an interruption of the nigrostriate tract.

         II. Dentatorubrothalamic tracts carry efferent fibers from the contralateral cerebellum.
 

48.    I. The caudate and putamen ganglia influence body position and muscle tone.

         II. Benedikt’s syndrome will manifest itself with an ipsilateral oculomotor palsy and
            contralateral tremor.
 

49.    I. The oculomotor nerve will leave the brain stem rostral to the posterior cerebral artery and
            caudal to the superior cerebellar artery.

         II. A cerebellar lesion can lead to ipsilateral paralysis of the upper or lower extremities.
 

50.    I. Some neurons in the caudate project to the thalamus.

         II. Neurons in the medial geniculate are involved in the auditory system.
 

Case Study

A patient comes in complaining that her right eye isn’t working correctly and she’s seeing double.
Also, when she tries to walk, her left leg shakes badly and she falls down. When she tries to
reach for something, her left arm and hand also shake.  You observe that when she is at rest,
there is no tremor. When asked to move her eyes to the right, both eyes move right.  You
notice a lateral strabismus of the right eye.  When you ask her to move her eyes left, the left eye
moves normally but the right eye does not move.  Further examination revealed that when the
patient has lost fine touch sensation in her left upper extremity but not her left lower extremity.
Right side body movement and sensory modalities are normal.

What is your preliminary diagnosis?
 
 

Case Study:  Likely midbrain stroke causing loss of  infarct to the right red nucleus,
which leads to left side intension tremors; right side oculomotor fibers running through
the red nucleus are affect, leading to right eye strabismus and abnormal lateral gaze.
The region of the medial lemniscus next to the red nucleus has also been damaged by
the stroke causing loss of fine touch in the upper extremities, but the region of the
medial lemniscus carrying fiber for the lower extremities is intact.