Neuroanatomy and Brain (Cerebrum, Brainstem, Cerebellum, Spinal Cord) MCQs

Anatomy · 86 free questions with answers & explanations.

1. A 45-year-old man presents with contralateral hemiplegia and ipsilateral CN III palsy following a midbrain infarct. Which tract is most likely interrupted to cause the contralateral motor deficit?
2. During a cerebellar examination, a patient shows past-pointing and intention tremor on the same side as the lesion. Which cerebellar structure, when damaged, most characteristically produces ipsilateral limb ataxia?
3. A hemisection of the spinal cord at T8 on the right produces which combination of deficits below the lesion?
4. The primary motor cortex for the lower limb is located in which gyrus and receives its blood supply predominantly from which artery?
5. A lesion at the dorsal column nuclei (nucleus gracilis and cuneatus) in the lower medulla would impair which sensory modality contralaterally?
6. A 58-year-old hypertensive man develops sudden-onset left hemiplegia with deviation of the head and eyes to the RIGHT and preserved consciousness. Damage to which structure best explains the conjugate eye deviation toward the right?
7. During a cerebellar examination, a patient shows intention tremor, dysdiadochokinesia, and ipsilateral limb ataxia but NO truncal ataxia or falling. The lesion most likely involves which part of the cerebellum?
8. A neonate born at term presents with myelomeningocele at L3–L4 and a Chiari II malformation on MRI. Which embryological event is the IMMEDIATE cause of the hindbrain herniation seen in Chiari II?
9. On T2-weighted MRI a lesion is found exclusively within the central grey matter of cervical spinal cord segments C5–C8, producing lower motor neuron signs in both hands but preserved spinothalamic sensation. Which pathway is MOST selectively affected?
10. A 55-year-old man develops sudden onset diplopia and ipsilateral facial numbness with contralateral hemiplegia. MRI shows a lesion in the pons. Which specific tract is most likely interrupted to cause the contralateral hemiplegia in this case?
11. In the spinal cord, the nucleus dorsalis of Clarke (Clark's column) is located at which lamina of Rexed, and what information does it relay?
12. A patient with a lateral medullary (Wallenberg) infarction characteristically shows loss of pain and temperature on the ipsilateral face and contralateral body. Which two structures are simultaneously damaged to explain this crossed pattern?
13. The dentate nucleus is the largest deep cerebellar nucleus. It receives Purkinje cell axons primarily from which part of the cerebellar cortex and projects to which structure via the superior cerebellar peduncle?
14. A neurology resident notes that a patient has 'internuclear ophthalmoplegia (INO)' — on lateral gaze to the right, the left eye does not adduct but the right eye abducts with nystagmus. Where is the causative lesion?
15. A 58-year-old man develops sudden onset of ipsilateral Horner syndrome, loss of pain and temperature on the ipsilateral face and contralateral body, dysphagia, dysarthria, and hiccups. Which artery is most likely occluded?
16. The Edinger-Westphal nucleus provides preganglionic parasympathetic fibres that synapse in the ciliary ganglion. These postganglionic fibres reach the sphincter pupillae and ciliary muscle via which nerve?
17. A patient has a lesion confined to the posterior limb of the internal capsule on the right side. Which combination of deficits is expected?
18. In the cerebellar cortex, the Purkinje cell axons project exclusively to which structure as the primary output pathway of the cerebellum?
19. Syringomyelia preferentially damages fibres crossing in the anterior white commissure of the spinal cord. Which specific tracts are affected earliest?
20. A 55-year-old man presents with ipsilateral loss of pain and temperature sensation on the face, contralateral loss of pain and temperature on the body, ipsilateral Horner syndrome, dysphagia, and ipsilateral cerebellar ataxia. Which artery is most likely occluded?
21. Lesion at the level of the left anterior horn cells at T10 spinal cord segment would produce which of the following deficits?
22. A cerebellar tumor in the flocculonodular lobe of a child presents characteristically with which of the following?
23. Which lamina of Rexed in the spinal cord gray matter is the principal site where nociceptive C-fibers synapse and contains the substantia gelatinosa?
24. A patient with a midbrain lesion has ipsilateral CN III palsy with contralateral hemiplegia. This is called Weber syndrome and involves damage to which specific structure alongside the corticospinal fibers?
25. A 45-year-old man presents with loss of pain and temperature on the right side of his face and left side of his body, along with ipsilateral Horner syndrome, hoarseness, and dysphagia. Which artery is most likely occluded?
26. During a neurological examination of a patient with a brainstem lesion, the examiner strokes the cornea lightly. The patient blinks on the ipsilateral side but not on the contralateral side. Which structure is most likely damaged?
27. A lesion in the dorsal column of the spinal cord at the T6 level on the right side will produce which sensory deficit?
28. A patient has a cerebellar hemisphere lesion on the right side. Which of the following clinical signs is expected?
29. The substantia nigra pars compacta projects to the striatum via the nigrostriatal pathway. Loss of these neurons in Parkinson's disease affects which neurotransmitter system and causes what net effect?
30. A 58-year-old man presents with ipsilateral Horner's syndrome, contralateral loss of pain and temperature, ipsilateral cerebellar ataxia, and dysphagia. MRI reveals an infarct in the lateral medulla. Which artery is most likely occluded?
31. The substantia gelatinosa of Rolando in the spinal cord receives which primary afferent fibers and modulates which sensory modality?
32. A lesion at the pontomedullary junction involving the medial longitudinal fasciculus (MLF) on the left side would produce which clinical deficit?
33. Which layer of the cerebellar cortex contains the cell bodies of Purkinje cells and is interposed between the molecular layer and the granular layer?
34. A 45-year-old presents with contralateral hemiplegia, hemianesthesia, and homonymous hemianopia, along with thalamic hand posture (flexion of wrist and metacarpophalangeal joints with extension of interphalangeal joints). Lesion at which site produces thalamic hand?
35. A 58-year-old man presents with left-sided hemiplegia, left hemisensory loss, and left homonymous hemianopia — the classic 'three hemisyndrome.' He also has left-sided hemiataxia. Occlusion of which vessel is most likely responsible?
36. During microsurgical dissection near the floor of the fourth ventricle, the surgeon must avoid a critical landmark located at the level of the facial colliculus. Which structure underlies the facial colliculus that, if damaged, causes facial palsy?
37. A patient with syringomyelia presents with bilateral loss of pain and temperature sensation in the upper limbs but preserved vibration and proprioception. Which anatomical feature explains this dissociated sensory loss?
38. On pupillary light reflex testing, the LEFT pupil constricts briskly to light shone in either eye, but the RIGHT pupil fails to constrict to light shone in either eye. There is no relative afferent pupillary defect. Where is the lesion?
39. A medical student studying the cerebellum notes that the deep cerebellar nuclei project to upper motor neurons via the superior cerebellar peduncle. After decussation in the midbrain, which thalamic nucleus relays cerebellar output to the motor cortex?
40. A 58-year-old hypertensive man develops sudden onset of ipsilateral Horner syndrome, hoarseness, dysphagia, loss of pain and temperature on the ipsilateral face and contralateral body, and ipsilateral limb ataxia. Which specific arterial territory is occluded?
41. A patient suffers a stab wound at the level of C8-T1 on the left side of the spinal cord, transecting the left half. Which motor and sensory deficits are expected below the lesion?
42. During a neurosurgical procedure in the posterior fossa, which nucleus in the floor of the 4th ventricle would be at risk of injury that could cause contralateral gaze palsy and ipsilateral facial palsy simultaneously?
43. The dentate nucleus of the cerebellum projects via the superior cerebellar peduncle to the contralateral red nucleus and thalamus (VL). A lesion of the right superior cerebellar peduncle after decussation (in the midbrain tegmentum) would produce cerebellar ataxia in which limbs?
44. A 45-year-old man has a lesion in the right paramedian pontine reticular formation (PPRF). What eye movement deficit would be expected?
45. A 45-year-old man develops a lesion at the level of the inferior olivary nucleus following a posterior inferior cerebellar artery (PICA) infarct. The inferior olivary nucleus forms a key relay in which cerebellar circuit?
46. During a surgical procedure for a meningioma at the foramen of Magendie, the surgeon must be cautious about which neuroanatomical relationship?
47. A patient with a lesion of the medial longitudinal fasciculus (MLF) between the abducens nucleus and the contralateral oculomotor nucleus will exhibit which specific pattern on lateral gaze testing?
48. The substantia gelatinosa of Rolando (lamina II of Rexed) in the spinal cord dorsal horn primarily receives input from which fiber type and plays what functional role?
49. A neurosurgeon planning stereotactic surgery for tremor in Parkinson's disease targets the ventral intermediate (VIM) nucleus of the thalamus. The VIM nucleus primarily relays signals from which source?
50. A patient with a lesion of the dentate nucleus (emboliform, globose, fastigial — together the deep cerebellar nuclei) would show ipsilateral cerebellar signs. The dentate nucleus projects via the superior cerebellar peduncle to the contralateral:
51. Which area of the hypothalamus is specifically responsible for the regulation of body temperature and is damaged in hyperthermia due to heat stroke?
52. The locus ceruleus, the primary noradrenergic nucleus of the brain, is located in the:
53. Damage to the mamillary bodies bilaterally, as seen in Wernicke's encephalopathy (thiamine deficiency), causes profound deficits in:
54. A 35-year-old woman presents with multiple episodes of sudden onset tinnitus, vertigo, and unilateral hearing loss lasting 20–30 minutes, with full recovery. MRI of the posterior fossa is normal. The endolymphatic hydrops underlying Ménière's disease involves distension of which membranous labyrinth structure?
55. A patient presents with intention tremor, dysdiadochokinesia, hypotonia, and scanning dysarthria on the right side only. The lesion is most likely in which cerebellar structure?
56. Brown-Séquard syndrome following a right hemisection of the spinal cord at T6 produces which combination of neurological deficits?
57. The corticospinal tract decussates at which level of the neuraxis, and what percentage of fibres cross in the pyramidal decussation?
58. A patient with a right cerebellar hemisphere lesion will demonstrate which combination of signs?
59. The dentate nucleus of the cerebellum projects efferent fibers via which peduncle to which contralateral structure?
60. The fastigial nucleus of the cerebellum projects primarily to which brainstem structures, and dysfunction is characterised by which clinical syndrome?
61. A lesion in the right anterior limb of the internal capsule most characteristically disrupts which connections?
62. A patient has a Brown-Séquard syndrome at C6 on the right. Which combination of findings is internally consistent with a RIGHT C6 hemicord lesion?
63. Syringomyelia classically produces a 'cape-like' distribution of pain and temperature loss with preserved proprioception. This pattern results from damage to which fibres in the spinal cord?
64. A patient has a lesion in the right hemisphere involving the arcuate fasciculus. The expected language deficit is:
65. In the substantia nigra pars compacta, dopaminergic neurons degenerate in Parkinson disease. The substantia nigra projects dopaminergic fibres primarily to which striatal nucleus, forming the nigrostriatal pathway?
66. A bilateral lesion of the mammillary bodies (as seen in Wernicke encephalopathy) primarily damages which functional circuit?
67. A 65-year-old patient presents with 'top of the basilar' syndrome. Which cluster of deficits is most characteristic?
68. Which nucleus in the basal ganglia circuit is the primary inhibitory output station that projects to the thalamus, and what neurotransmitter does it use?
69. A patient suffers a lesion of the right dentate nucleus. What movement disorder would be expected ipsilaterally?
70. A patient with a right middle cerebral artery (MCA) infarct has left hemiplegia, left hemianesthesia, and left homonymous hemianopia (visual field defect). The homonymous hemianopia is due to involvement of which structure in the MCA territory?
71. In syringomyelia, the syrinx cavity expands within the central spinal cord, first destroying which fiber type, producing the characteristic clinical pattern?
72. The dentate nucleus of the cerebellum is the largest and most lateral of the cerebellar nuclei. Efferent fibers from the dentate nucleus leave via which cerebellar peduncle to reach the contralateral red nucleus and thalamus?
73. Brown-Séquard syndrome due to right hemicord lesion at T6 produces which combination of deficits?
74. Lesions of the dentate nucleus of the cerebellum produce ipsilateral limb ataxia. The dentate nucleus projects primarily through which cerebellar peduncle?
75. Which cortical area is responsible for the voluntary control of conjugate horizontal gaze to the contralateral side, such that damage results in ipsilateral gaze deviation (eyes deviate toward the lesion)?
76. In Brown-Séquard syndrome following a right hemisection of the spinal cord at T6, which combination of findings is correct?
77. The internal capsule posterior limb transmits all of the following EXCEPT:
78. The cerebellar hemisphere lesion produces ipsilateral ataxia primarily because:
79. Brown-Séquard syndrome results from hemisection of the spinal cord. Below the level of the lesion on the side of the lesion, one would find:
80. The limbic system includes the hippocampus, amygdala, cingulate gyrus, and mammillary bodies. The primary role of the amygdala in emotion processing is:
81. A patient has a lesion of the right parietal lobe (supramarginal gyrus, Brodmann area 40). The expected deficit would be:
82. A 68-year-old man with atrial fibrillation develops sudden right hemiplegia and a right homonymous hemianopia. A few hours later he becomes drowsy. CT shows a large hypodense area in the territory of the left middle cerebral artery. Which additional finding is expected on neurological exam?
83. A patient presents with contralateral hemiplegia, ipsilateral oculomotor palsy (CN III palsy) with a dilated pupil, and ptosis. The lesion is localized to:
84. A 32-year-old presents with sudden-onset headache, neck stiffness, and photophobia. LP shows xanthochromia. CT angiography reveals an aneurysm at the junction of the internal carotid artery and posterior communicating artery. Which CN is most at risk from this aneurysm?
85. The lateral spinothalamic tract carries pain and temperature sensation. At which level do the second-order neurons decussate before ascending to the thalamus?
86. A 45-year-old woman with multiple sclerosis develops scanning speech, intention tremor, and nystagmus. These signs together are known as Charcot's triad and indicate a lesion in which structure?