Neuroanatomy — Tracts, Nuclei and Lesion Localization (Advanced) MCQs

Anatomy · 51 free questions with answers & explanations.

1. A 58-year-old hypertensive man develops sudden-onset right-sided limb ataxia, ipsilateral Horner's syndrome, loss of pain and temperature over the left face and right body, and dysphagia. MRI shows an infarct in the lateral medulla. Which artery is most likely occluded?
2. A patient presents with loss of vibration and proprioception below T10 on the right side, and loss of pain and temperature below T10 on the left side, with right-sided upper motor neurone signs below the lesion. This pattern is consistent with damage at which level and side?
3. Occlusion of paramedian branches of the basilar artery at the pontine level causes ipsilateral abducens palsy, ipsilateral facial LMN palsy, and contralateral hemiplegia. This is known as:
4. The nucleus gracilis and nucleus cuneatus, which relay the dorsal column-medial lemniscal pathway, are located in the:
5. A patient with a midbrain lesion presents with ipsilateral oculomotor nerve palsy and contralateral intention tremor and ataxia (no hemiplegia). The red nucleus is involved. This is:
6. A 58-year-old man suddenly develops right-sided hemiplegia with ipsilateral third nerve palsy and contralateral loss of proprioception in the arm. The lesion is located in the:
7. Lesion of the right lateral medulla (Wallenberg syndrome) produces loss of pain and temperature over the right face and left body. The tract responsible for contralateral body sensory loss travels in the:
8. A patient with a midline pontine lesion at the level of the abducent nucleus develops convergent squint and inability to abduct both eyes, but vertical gaze is intact. The most likely structure damaged besides the abducent nucleus is the:
9. In the internal capsule, the corticobulbar fibres occupying the genu are somatotopically arranged such that fibres to the lower face motor cortex lie:
10. A patient loses all conscious proprioception and discriminative touch from the right lower limb with preservation of pain/temperature. MRI shows a T2-bright lesion at T8 level right posterior column. Fibres carrying proprioception from the right lower limb travel in which fasciculus and on which side at C5 level?
11. A 58-year-old man develops sudden onset of right-sided facial pain and temperature loss along with left-sided body pain and temperature loss below the neck, right-sided Horner syndrome, dysphagia, and hoarseness. MRI shows a lesion in the right dorsolateral medulla. Which of the following best explains the ipsilateral facial sensory loss?
12. A patient presents with bilateral loss of pain and temperature sensation across the upper limbs and shoulders in a 'cape-like' distribution, with preservation of fine touch and proprioception. Motor function is intact. Where is the lesion most likely located?
13. Damage to the right dorsal column at the T10 level will cause loss of which modality in which body part?
14. A 65-year-old develops sudden right hemiplegia with right facial weakness of the upper motor neuron type, along with deviation of the tongue to the right on protrusion. Which structure is most likely injured?
15. In Brown-Séquard syndrome affecting the right hemicord at C6, which combination of deficits is expected BELOW the lesion?
16. A 58-year-old man develops sudden right-sided hemiplegia with right lower facial weakness and leftward tongue deviation on protrusion. Sensation is intact bilaterally. Where is the lesion?
17. A patient with a right posterior inferior cerebellar artery (PICA) infarct has ipsilateral Horner syndrome, loss of pain and temperature over the right face, and contralateral loss of pain and temperature over the body. Which nucleus is responsible for the ipsilateral facial sensory loss?
18. Selective damage to Brodmann area 44 in the dominant hemisphere produces which precisely defined deficit?
19. A patient with a left thalamic infarct affecting the ventral posterolateral (VPL) nucleus has contralateral hemisensory loss. Which thalamic nucleus relays cerebellar and basal ganglia output to motor cortex?
20. A 45-year-old woman presents with bilateral ptosis, loss of vertical gaze, and convergence retraction nystagmus on attempted upgaze, with preserved horizontal eye movements. Which structure is damaged?
21. The dentato-rubro-thalamic tract (DRTT) decussates in which structure before reaching the contralateral thalamus?
22. Damage to the medial longitudinal fasciculus (MLF) on the left side causes which characteristic eye movement disorder?
23. A 58-year-old man develops sudden onset of ipsilateral Horner syndrome, ipsilateral facial pain and temperature loss, contralateral body pain and temperature loss, ipsilateral limb ataxia, and hiccups. Which specific structure is infarcted?
24. A patient with a midbrain tegmental lesion shows loss of vertical gaze upward, convergence-retraction nystagmus on attempted upgaze, and light-near dissociation of pupils. Which nucleus is specifically damaged?
25. A lesion confined to the right medial longitudinal fasciculus (MLF) between the abducens and oculomotor nuclei produces which characteristic eye movement abnormality?
26. The fastigial nucleus of the cerebellum projects primarily to which target, and damage to this nucleus alone produces what clinical finding?
27. A patient has pure hemisensory loss on the right side (face, arm, and leg equally) for all modalities without motor deficits. The most likely lesion site is:
28. A 52-year-old man presents with sudden onset left-sided face and right-sided body loss of pain and temperature sensation, hoarseness, dysphagia, and ipsilateral Horner's syndrome. MRI shows an infarct in the territory of the posterior inferior cerebellar artery. Which structure, when damaged, produces the ipsilateral facial sensory loss in this syndrome?
29. A patient has a lesion at the level of the right pontine tegmentum affecting the medial longitudinal fasciculus (MLF). On testing horizontal gaze to the left, which finding is expected?
30. Lesion of the left dorsolateral funiculus at the T6 level produces which precise pattern of deficit?
31. A patient with a right temporal lobe lesion extending into the deep white matter shows a visual field defect. Which field defect is most characteristic?
32. The Edinger-Westphal nucleus sends preganglionic parasympathetic fibers via CN III to the ciliary ganglion. These fibers synapse and give rise to short ciliary nerves innervating which two structures?
33. A patient presents with pure motor hemiplegia of the right arm and leg without sensory, speech, or visual deficits. MRI reveals a small infarct. Where is the most likely location?
34. Bilateral lesion of the flocculus and nodulus of the cerebellum would most specifically impair which function?
35. A 58-year-old hypertensive man presents with sudden onset of ipsilateral Horner syndrome, ipsilateral loss of pain and temperature over the face, contralateral loss of pain and temperature over the body, ipsilateral limb ataxia, and dysphagia. Which nucleus within the medullary tegmentum is the primary site of this infarct?
36. Lesion of the right medial longitudinal fasciculus (MLF) between the abducens nucleus and oculomotor nucleus produces which characteristic eye movement abnormality?
37. A patient has pure hemisensory loss (face, arm, trunk, leg equally) with no motor or cerebellar findings. MRI shows a small infarct. The most likely location of the lesion is:
38. The spinothalamic tract decussates within the spinal cord at which level relative to the dermatome of entry?
39. A 45-year-old man develops progressive ataxic gait, dysarthria, and nystagmus. MRI shows atrophy of the anterior vermis. Which tract is primarily responsible for relaying proprioceptive input from the lower limb to the cerebellum via this vermal pathway?
40. A 52-year-old man presents with loss of pain and temperature sensation on the right side of his face and the left side of his body, with ipsilateral Horner syndrome and dysphagia. Which artery is most likely occluded?
41. A patient with a brainstem lesion shows contralateral hemiplegia and ipsilateral oculomotor nerve palsy. The lesion is most precisely located in the:
42. The gracile nucleus in the medulla receives first-order neurons from which spinal cord levels?
43. A unilateral lesion of the superior colliculus would most directly impair which function?
44. The anterolateral system (spinothalamic tract) decussates at which level relative to the dermatome of entry?
45. A 58-year-old man develops sudden-onset ipsilateral facial analgesia with contralateral limb analgesia, ipsilateral Horner syndrome, dysphagia, and hoarseness. The lesion responsible is in the:
46. The mesencephalic nucleus of the trigeminal nerve is unique among cranial nerve sensory nuclei because it contains:
47. A patient sustains a lesion at the right pontine tegmentum affecting the abducens nucleus. The expected eye movement deficit would be:
48. Damage to which tract produces loss of conscious proprioception (vibration and joint position sense) in the ipsilateral lower limb?
49. A 42-year-old woman has a focal lesion of the right red nucleus in the midbrain tegmentum. The expected clinical finding is:
50. The anterior spinocerebellar tract is unique among spinocerebellar pathways because it:
51. A patient develops internuclear ophthalmoplegia (INO): on attempting right lateral gaze, the right eye abducts normally but the left eye fails to adduct and shows monocular nystagmus of the abducting right eye. The lesion is in the: