neuroanatomy 3rd Comprehensive Examination 1 - 50 Flashcards
Comprehensive Examination 1 - 50
1. The cuneus is separated from the lingual gyrus by the (A) rhinal sulcus (B) calcarine sulcus (C) parietooccipital sulcus (D) collateral sulcus (E) intraparietal sulcus
l-B. The calcarine sulcus separates the cuneus from the lingual gyrus. The banks of the calcarine sulcus contain the visual cortex.
2. Which sinus receives drainage from the greatest number of arachnoid granulations? (A) Straight sinus (B) Transverse sinus (C) Sigmoid sinus (D) Superior sagittal sinus (E) Cavernous sinus
2-D. The superior sagittal sinus receives drainage from the greatest number of arachnoid granulations.
3. Which of the following statements concerning the Rathke pouch is true? (A) It is a mesodermal diverticulum (B) It is derived from the neural tube (C) It gives rise to the adenohypophysis (D) It gives rise to the epiphysis (E) It gives rise to the neurohypophysis
3-C. The Rathke pouch is an ectodermal outpocketing of the stomodeum anterior to the buccopharyngeal membrane and gives rise to the adenohypophysis (pars distalis, pars tuberalis, and
pars intermedia).
- Which of the following statements concerning the lateral horn of the spinal cord is true?
(A) It contains preganglionic parasympathetic neurons
(B) It gives rise to a spinocerebellar tract
(C) It is present at all spinal cord levels
(D) It gives rise to preganglionic sympathetic fibers
(E) It is most prominent at sacral levels
4-D. The lateral horn (T1-L3) gives rise to preganglionic sympathetic fibers.
- Which of the following statements concerning the nucleus dorsalis of Clarke is true?
(A) It is found in the ventral horn
(B) It projects to the cerebellum
(C) It is present at all spinal levels
(D) It is most prominent at upper cervical levels
(E) It is homologous to the cuneate nucleus of the medulla
5-B. The nucleus dorsalis of Clarke (C8-L3) gives rise to the dorsal spinocerebellar tract, which ascends and enters the cerebellum through the inferior cerebellar peduncle.
6. Which of the following groups of cranial nerves is closely related to the corticospinal tract? (A) CN III, CN IV, and CN V (B) CN III, CN V, and CN VII (C) CN III, CN VI, and CN VIII (D) CN III, CN VI, and CN XII (E) CN III, CN IX, and CN X
6-D. In the midbrain, the pyramidal tract lies in the basis pedunculi; oculomotor fibers of CN
III pass through the medial part of the basis pedunculi. In the pons, the pyramidal tract lies in the base of the pons; abducent fibers of CN VI pass through the lateral part of the pyramidal fasciculi. In the medulla, the pyramidal tracts form the medullary pyramids; hypoglossal fibers of
CN XII lie just lateral to the pyramids.
7. The primary auditory cortex is located in the (A) frontal operculum (B) postcentral gyrus (C) superior parietal lobule (D) inferior parietal lobule (E) transverse temporal gyri
7-E. The primary auditory cortex (i.e., areas 41 and 42) is located in the transverse temporal
gyri of Heschl, a part of the superior temporal gyrus.
8. The neocerebellum projects to the motor cortex via the (A) anterior thalamic nucleus (B) ventral anterior nucleus (C) ventral lateral nucleus (D) lateral dorsal nucleus (E) lateral posterior nucleus
8-C. The neocerebellum (the posterior lobe minus the vermis and the paravermis) sends input to the motor cortex through the ventral lateral nucleus of the thalamus. The pathway is the neocerebellar cortex, dentate nucleus, contralateral ventral lateral nucleus of the thalamus, and motor cortex (area 4).
9. The dentatothalamic tract decussates in the (A) diencephalon (B) rostral midbrain (C) caudal midbrain (D) rostral pons (E) caudal pons
9-C. The dentatothalamic tract decussates in the caudal midbrain tegmentum at the level of the
inferior colliculus. This massive decussation of the superior cerebellar peduncles is characteris-
tic of this level.
10. A pituitary tumor is most frequently associated with a(an) (A) homonymous hemianopia (B) homonymous quadrantanopia (C) bitemporal hemianopia (D) binasal hemianopia (E) altitudinal hemianopia
10-C. Pituitary tumors frequently compress the decussating fibers of the optic chiasm and pro-
duce a bitemporal hemianopia. Nasal fibers decussate, and temporal fibers remain ipsilateral.
- Resection of the anterior portion of the left temporal lobe is most frequently associated
with a
(A) left homonymous hemianopia
(B) right upper homonymous quadrantanopia
(C) right lower homonymous quadrantanopia
(D) left upper homonymous quadrantanopia
(E) left lower homonymous quadrantanopia
11-B. Resection of the anterior portion of the temporal lobe transects the fibers of the loop of Meyer and results in a contralateral upper homonymous quadrantanopia. Inferior retinal quadrants are represented in the inferior banks of the calcarine sulcus.
- A 65-year-old farmer has experienced dull frontal headaches for the last 3 weeks. Neurologic examination reveals spastic hemiparesis on the right side and a pronator drift on the
right side. What is the most likely diagnosis?
(A) Brain tumor
(B) Myasthenia gravis
(C) Progressive supranuclear palsy
(D) Pseudotumor cerebri
(E) Subacute combined degeneration
12-A. Headache and papilledema are signs of brain tumor, and pronator drift is a frontal lobe sign due to weakness of the supinator muscle. Tumor pressure on the corticospinal tract results
in contralateral spastic hemiparesis. In progressive supranuclear palsy the patient cannot look down, in myasthenia gravis there is weakness of skeletal muscle, in pseudotumor cerebri there
are no mass lesions but headache and papilledema, and in subacute combined degeneration the posterior columns and the corticospinal tracts are affected.
- An 18-year-old high school student has fractured a cervical vertebra in an automobile accident. Neurologic examination reveals hemiparesis on the right side, Babinski and
Hoffmann signs on the right side, loss of pain and temperature sensation on the left side, and normal pallesthesia in all extremities. The spinal cord lesion that would most likely explain the deficits involves the
(A) dorsal column, left side
(B) dorsal column, right side
(C) lateral column, left side
(D) lateral column, right side
(E) anterior column, bilateral
13-D. The lateral corticospinal tract and the lateral spinothalamic tract are both found in the lateral column. Transection of the corticospinal tract results in an ipsilateral paresis, and transection of the spinothalamic tract results in a contralateral loss of pain and temperature sensation. Pallesthesia (vibration sense) is normal.
14. Light shone into the left eye elicits a direct pupillary reflex but no consensual reflex. A lesion in which of the following structures ac-counts for this deficit? (A) Optic nerve, left eye (B) Optic nerve, right eye (C) Optic tract, right side (D) Oculomotor nerve, right side (E) Oculomotor nerve, left side
14-D. The contralateral oculomotor nerve is responsible for the consensual reaction.
15. A 53-year-old housewife has a normal corneal blink reflex on her left side but no consensual blink on her right side. Which of the following neurologic deficits or signs would you expect to find on the right side? (A) Hyperacusis (B) Hemianhidrosis (C) Hemianesthesia (D) Internal ophthalmoplegia (E) Severe ptosis
15-A. Hyperacusis is an increased acuity of hearing and undue sensitivity to low tones. It results from paralysis of the stapedius muscle (CN VII); the stapedius reduces the amplitude of sound vibrations of the stapes in the oval window.
- A 49-year-old man has a loss of tactile sensation involving the anterior two-thirds of his tongue on the left side. Neurologic examination reveals paralysis of the masseter muscle on the left side and loss of pain and temperature sensation from the teeth of the mandible on the left side. He has a lesion involving which one of the following nerves?
(A) Chorda tympani nerve
(B) Facial nerve
(C) Hypoglossal nerve
(D) Trigeminal nerve, mandibular division
(E) Trigeminal nerve, ophthalmic division
16-D. The mandibular division of the trigeminal nerve (CN V-3) innervates the muscles of mastication (e.g., masseter muscle) and mediates the tactile sensation of the anterior two-thirds of the tongue. The glossopharyngeal nerve (CN IX) provides the tactile, nociceptive, and taste innervation of the posterior one-third of the tongue. The facial nerve (CN VII) provides taste innervation to the anterior two-thirds of the tongue.
17. A 62-year-old lawyer suffers a stroke and falls while cutting his lawn. He does not lose consciousness. Neurologic examination reveals loss of pain sensation on the right side of the face and on the left side of the body, falling and past pointing to the right side, difficulty swallowing, horizontal nystagmus to the right side, deviation of the uvula to the left when asked to say "ah," and Horner syndrome on the right side. The most likely site of this man's lesion is the (A) Internal capsule, left side (B) Midbrain, right side (C) Pontine tegmentum (D) Lateral medulla, right side (E) Medial medulla, right side
17-D. This is the classic lateral medullary syndrome, which is also known as Wallenberg syndrome (see Figure 14-IB).
18. A 64-year-old pharmacology professor complains of weakness in his right leg and double vision, especially when moving his eyes to the left. Neurologic examination reveals a dilated pupil and ptosis on the left side and a Babinski sign (extensor plantar reflex) on the right side. The most likely site of this patient's lesion is the (A) Midbrain crus cerebri, right side (B) Midbrain crus cerebri, left side (C) Pontine base, left side (D) Pontine tegmentum, right side (E) Internal capsule, right side
18-B. This is a classic medial midbrain lesion characteristic of Weber syndrome. It includes the crus cerebri and the exiting intra-axial fibers of the oculomotor nerve (see Figure 14-3C).
- While working in his shop, a 21-year-old machinist is struck by a penetrating metal fragment in the side of the head. Neurologic examination reveals the following language deficits: fluent speech, no ability to read aloud, no ability to repeat what you say, no ability to compensate by writing. The patient understands the problem but cannot resolve it.
Where would you expect to find the fragment?
(A) Between the supramarginal gyrus and
the inferior frontal gyrus
(B) In the angular gyrus
(C) In the transverse gyri
(D) In the posterior one-third of the superior temporal gyrus
(E) In the paracentral gyrus
19-A. The metal fragment is found between the inferior frontal gyrus and the supramarginal gyrus. The two gyri are connected by the arcuate fasciculus; transection results in conduction
aphasia. The arcuate fasciculus interconnects Broca area from Wernicke area. The key deficit is the inability to repeat (see Figure 24-1).
- The catecholamine norepinephrine is the primary neurotransmitter found in the
(A) adrenal cortex
(B) adrenal medulla
(C) postganglionic parasympathetic neurons to the circular smooth muscle layer of the jejunum
(D) postganglionic sympathetic neurons to the smooth muscle of the renal arterioles
(E) postganglionic sympathetic neurons to the sweat glands
20-D. Norepinephrine is the neurotransmitter of postganglionic sympathetic neurons, with the
exception of sweat glands and some blood vessels that receive cholinergic sympathetic innervation. Epinephrine is produced by the chromaffin cells of the adrenal medulla.
