COMSAE Form 113 Practice Test:
Comprehensive Review for COMLEX
Preparation with questions and answers
with rationales/graded A+/2026
update/100% correct
Neuroanatomy & Neurology
Question 1
A 20-year-old female presents to the emergency department after slipping on ice
and hitting her mouth on the sidewalk. Her medial maxillary incisors are fractured,
and she is in intense pain. The nerve most likely conveying this pain sensation is
which of the following?
A) Anterior superior alveolar
B) Infraorbital
C) Middle superior alveolar
D) Nasopalatine
Correct Answer: B) Infraorbital
Rationale: The infraorbital nerve is a branch of the maxillary nerve (CN V2),
which provides sensory innervation to the maxillary teeth, upper gingiva, and the
skin of the lower eyelid, lateral nose, and upper lip. The fractured maxillary
incisors would stimulate nerve endings in this distribution. The infraorbital nerve
travels through the infraorbital canal and emerges on the face through the
infraorbital foramen, supplying sensation to the areas affected by this dental
injury .
Question 2
A 25-year-old female presents for evaluation of headaches, diplopia, and loss of
peripheral vision that have progressively worsened over the past week. She reports
galactorrhea and amenorrhea. Physical examination is unremarkable, and Beta-
,HCG is negative for pregnancy. MRI of the brain is obtained. The secretory cells
most likely causing this patient's conditions are:
A) Corticotrophs
B) Gonadotrophs
C) Lactotrophs
D) Somatotrophs
Correct Answer: C) Lactotrophs
Rationale: The symptoms of headaches, diplopia, and peripheral vision loss (from
optic chiasm compression) along with galactorrhea and amenorrhea are classic for
a prolactin-secreting pituitary adenoma. Lactotrophs are the cells in the anterior
pituitary responsible for producing and secreting prolactin. Hyperprolactinemia
inhibits gonadotropin release, causing amenorrhea, and stimulates breast milk
production (galactorrhea). The mass effect from the adenoma causes the visual
symptoms and headaches .
Question 3
A 62-year-old man is experiencing several falls at home. Past medical history is
significant for uncontrolled hypertension with step-wise deterioration in memory.
An MRI of the brain is most likely to show which of the following?
A) Multiple lacunar infarcts in the basal ganglia
B) A single large middle cerebral artery territory infarct
C) Subarachnoid hemorrhage
D) Normal study
Correct Answer: A) Multiple lacunar infarcts in the basal ganglia
Rationale: The patient's history of uncontrolled hypertension with step-wise
deterioration in memory and falls suggests vascular dementia due to small vessel
disease. Hypertension causes lipohyalinosis of small penetrating arteries, leading to
multiple lacunar infarcts, particularly in the basal ganglia, thalamus, and deep
white matter. This pattern is characteristic of subcortical vascular dementia .
Question 4
A patient presents with left-sided weakness. Muscle strength is reduced in both left
, limbs. The plantar reflex is extensor on the left and flexor on the right. Protrusion
of the tongue deviates to the right. Which sensory deficit is most likely present?
A) Loss of pain and temperature sensation on the right arm and leg
B) Loss of discriminative touch on the left arm and leg
C) Loss of pain and temperature sensation on the left face
D) Loss of all sensory modalities on the right side
Correct Answer: B) Loss of discriminative touch on the left arm and leg
Rationale: This pattern indicates a medial medullary lesion (medial medullary
syndrome). The medial medulla contains the corticospinal tract (causing
contralateral weakness), the medial lemniscus (causing contralateral loss of
discriminative touch and proprioception), and the hypoglossal nerve fibers
(causing ipsilateral tongue deviation). Pain and temperature are spared because
they are carried in the lateral spinothalamic tract, which is located in the lateral
medulla .
Question 5
A patient presents with a new-onset seizure. An MRI reveals a lesion in the right
hippocampus. The patient is started on levetiracetam. Which of the following best
describes the mechanism of action of this medication?
A) Sodium channel blockade
B) GABA-A receptor potentiation
C) Synaptic vesicle protein 2A binding
D) Calcium channel blockade
Correct Answer: C) Synaptic vesicle protein 2A binding
Rationale: Levetiracetam is an anticonvulsant that binds to synaptic vesicle
protein 2A (SV2A), which is involved in vesicle fusion and neurotransmitter
release. This unique mechanism distinguishes it from other antiseizure
medications. Phenytoin and carbamazepine are sodium channel blockers;
benzodiazepines potentiate GABA-A receptors; and ethosuximide blocks T-type
calcium channels .
Comprehensive Review for COMLEX
Preparation with questions and answers
with rationales/graded A+/2026
update/100% correct
Neuroanatomy & Neurology
Question 1
A 20-year-old female presents to the emergency department after slipping on ice
and hitting her mouth on the sidewalk. Her medial maxillary incisors are fractured,
and she is in intense pain. The nerve most likely conveying this pain sensation is
which of the following?
A) Anterior superior alveolar
B) Infraorbital
C) Middle superior alveolar
D) Nasopalatine
Correct Answer: B) Infraorbital
Rationale: The infraorbital nerve is a branch of the maxillary nerve (CN V2),
which provides sensory innervation to the maxillary teeth, upper gingiva, and the
skin of the lower eyelid, lateral nose, and upper lip. The fractured maxillary
incisors would stimulate nerve endings in this distribution. The infraorbital nerve
travels through the infraorbital canal and emerges on the face through the
infraorbital foramen, supplying sensation to the areas affected by this dental
injury .
Question 2
A 25-year-old female presents for evaluation of headaches, diplopia, and loss of
peripheral vision that have progressively worsened over the past week. She reports
galactorrhea and amenorrhea. Physical examination is unremarkable, and Beta-
,HCG is negative for pregnancy. MRI of the brain is obtained. The secretory cells
most likely causing this patient's conditions are:
A) Corticotrophs
B) Gonadotrophs
C) Lactotrophs
D) Somatotrophs
Correct Answer: C) Lactotrophs
Rationale: The symptoms of headaches, diplopia, and peripheral vision loss (from
optic chiasm compression) along with galactorrhea and amenorrhea are classic for
a prolactin-secreting pituitary adenoma. Lactotrophs are the cells in the anterior
pituitary responsible for producing and secreting prolactin. Hyperprolactinemia
inhibits gonadotropin release, causing amenorrhea, and stimulates breast milk
production (galactorrhea). The mass effect from the adenoma causes the visual
symptoms and headaches .
Question 3
A 62-year-old man is experiencing several falls at home. Past medical history is
significant for uncontrolled hypertension with step-wise deterioration in memory.
An MRI of the brain is most likely to show which of the following?
A) Multiple lacunar infarcts in the basal ganglia
B) A single large middle cerebral artery territory infarct
C) Subarachnoid hemorrhage
D) Normal study
Correct Answer: A) Multiple lacunar infarcts in the basal ganglia
Rationale: The patient's history of uncontrolled hypertension with step-wise
deterioration in memory and falls suggests vascular dementia due to small vessel
disease. Hypertension causes lipohyalinosis of small penetrating arteries, leading to
multiple lacunar infarcts, particularly in the basal ganglia, thalamus, and deep
white matter. This pattern is characteristic of subcortical vascular dementia .
Question 4
A patient presents with left-sided weakness. Muscle strength is reduced in both left
, limbs. The plantar reflex is extensor on the left and flexor on the right. Protrusion
of the tongue deviates to the right. Which sensory deficit is most likely present?
A) Loss of pain and temperature sensation on the right arm and leg
B) Loss of discriminative touch on the left arm and leg
C) Loss of pain and temperature sensation on the left face
D) Loss of all sensory modalities on the right side
Correct Answer: B) Loss of discriminative touch on the left arm and leg
Rationale: This pattern indicates a medial medullary lesion (medial medullary
syndrome). The medial medulla contains the corticospinal tract (causing
contralateral weakness), the medial lemniscus (causing contralateral loss of
discriminative touch and proprioception), and the hypoglossal nerve fibers
(causing ipsilateral tongue deviation). Pain and temperature are spared because
they are carried in the lateral spinothalamic tract, which is located in the lateral
medulla .
Question 5
A patient presents with a new-onset seizure. An MRI reveals a lesion in the right
hippocampus. The patient is started on levetiracetam. Which of the following best
describes the mechanism of action of this medication?
A) Sodium channel blockade
B) GABA-A receptor potentiation
C) Synaptic vesicle protein 2A binding
D) Calcium channel blockade
Correct Answer: C) Synaptic vesicle protein 2A binding
Rationale: Levetiracetam is an anticonvulsant that binds to synaptic vesicle
protein 2A (SV2A), which is involved in vesicle fusion and neurotransmitter
release. This unique mechanism distinguishes it from other antiseizure
medications. Phenytoin and carbamazepine are sodium channel blockers;
benzodiazepines potentiate GABA-A receptors; and ethosuximide blocks T-type
calcium channels .
