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
1–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. It gives rise to the adenohypophysis (pars distalis, pars tuberalis, and
pars intermedia).
4–D. The lateral horn (T1–L3) gives rise to preganglionic sympathetic fibers.
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 (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 characteristic
of this level.
10. A pituitary tumor is most frequently associated with (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 produce
a bitemporal hemianopia. Nasal fibers decussate, and temporal fibers remain ipsilateral.
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.
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. In subacute combined degeneration the posterior
columns and the corticospinal tracts are affected.
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 ipsilateral paresis, and transection of
the spinothalamic tract results in 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 accounts 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. Hyperacusis is 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.
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 third of the tongue. The facial nerve (CN VII) provides taste innervation to
the anterior two-thirds of the tongue.
17–D. This is the classic lateral medullary syndrome, which is also known as Wallenberg syndrome
(see Figure 14-1B).
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).
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 and Wernicke area. The key deficit is the
inability to repeat (see Figure 24-1).
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.
21–D. Bilateral damage of the medial temporal gyri, including the amygdalae, may cause severe
memory loss (hippocampal formations). Such damage to the amygdalae may lead to inappropriate
social behavior (e.g., hyperphagia, hypersexuality, general disinhibition). Bilateral destruction
of the amygdalae results in Klüver-Bucy syndrome.
22. A 55-year-old woman has difficulty reading small print. She most likely has (A) Astigmatism (B) Cataracts (C) Optic atrophy (D) Macular degeneration (E) Presbyopia
22–E. Presbyopia is progressive loss of the ability to accommodate, the decreased ability to focus
on near objects. Astigmatism is the difference in refracting power of the cornea and lens in different
meridians. Cataracts are opacities of the lens that appear with aging. Optic atrophy is
degeneration of the optic nerve and papillomacular bundle and loss of central vision.
23–E. The corticospinal fibers are not completely myelinated at birth; this does not occur until
18 months to 2 years of age. During this time, the Babinski reflex can be elicited; later it is suppressed.
24. Special visceral afferent neurons that innervate receptor cells in taste buds synapse in the (A) Geniculate ganglion (B) Inferior salivatory nucleus (C) Nucleus of the solitary tract (D) Spinal trigeminal nucleus (E) Ventral posteromedial nucleus
24–C. The nucleus of the solitary tract receives taste fibers from cranial nerves VII, IX, and X.
Neurons of this tract project to the ventral posteromedial nucleus of the thalamus.