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Question 1Neuroanatomy and Physiology

Which cerebral lobe contains the primary motor cortex that directs voluntary movement of the contralateral side of the body?

  1. Parietal lobe
  2. Occipital lobe
  3. Temporal lobe
  4. Frontal lobe Correct answer.

Explanation

The primary motor cortex sits in the precentral gyrus of the frontal lobe and generates voluntary movement on the opposite side of the body. The parietal lobe handles somatic sensation, while the temporal and occipital lobes serve auditory, language, and visual functions.

Question 2Neuroanatomy and Physiology

Cerebrospinal fluid is produced mainly by which structure?

  1. Pituitary gland
  2. Arachnoid granulations
  3. Pineal gland
  4. Choroid plexus Correct answer.

Explanation

The choroid plexus of the lateral, third, and fourth ventricles secretes the majority of cerebrospinal fluid. Arachnoid granulations serve the opposite role, returning CSF to the dural venous sinuses.

Question 3Neuroanatomy and Physiology

Which cranial nerve innervates the muscles of mastication?

  1. Hypoglossal nerve (CN XII)
  2. Glossopharyngeal nerve (CN IX)
  3. Trigeminal nerve (CN V) Correct answer.
  4. Facial nerve (CN VII)

Explanation

The motor division of the trigeminal nerve supplies the masseter, temporalis, and pterygoid muscles that close and grind the jaw. The jaw jerk reflex is likewise carried by this nerve.

Question 4Neuroanatomy and Physiology

According to the Monro-Kellie hypothesis, which intracranial component is displaced first in response to a slowly expanding mass?

  1. Cerebral venous blood
  2. Cerebrospinal fluid Correct answer.
  3. Brain parenchyma
  4. Cerebral arterial blood

Explanation

The skull is a rigid container holding brain, blood, and CSF in a fixed volume, so an added mass must be offset by an equal loss of one of these components. CSF is displaced into the spinal subarachnoid space and absorbed more rapidly first, with venous blood giving way next as compensation is exhausted.

Question 5Neuroanatomy and Physiology

Which structure serves as the principal relay station for sensory pathways traveling to the cerebral cortex?

  1. Amygdala
  2. Hypothalamus
  3. Thalamus Correct answer.
  4. Hippocampus

Explanation

Every sensory modality except olfaction synapses in the thalamus before projecting to its cortical area. The thalamus also relays motor information from the basal ganglia and cerebellum.

Question 6Neuroanatomy and Physiology

Cerebral autoregulation holds cerebral blood flow relatively constant across which mean arterial pressure range in adults?

  1. 20 to 50 mm Hg
  2. 40 to 90 mm Hg
  3. 60 to 150 mm Hg Correct answer.
  4. 160 to 220 mm Hg

Explanation

Within roughly 60 to 150 mm Hg mean arterial pressure, cerebral arterioles constrict or dilate to keep flow near 50 mL per 100 g of tissue per minute. Outside this plateau, flow becomes pressure-passive, leaving the brain vulnerable to ischemia at low pressures and to edema at high pressures.

Question 7Neuroanatomy and Physiology

Rupture of a berry aneurysm at which location most commonly causes nontraumatic subarachnoid hemorrhage?

  1. Middle meningeal artery of the external carotid system
  2. Basilar artery of the posterior circulation
  3. Anterior communicating artery Correct answer.
  4. Posterior inferior cerebellar artery

Explanation

Aneurysms of the anterior communicating artery are the most frequent source of spontaneous subarachnoid hemorrhage, presenting with sudden severe headache. They sit at a branch point of the circle of Willis where hemodynamic stress is greatest.

Question 8Neuroanatomy and Physiology

At which spinal level is the nipple line dermatome located?

  1. T10
  2. C3
  3. T4 Correct answer.
  4. C6

Explanation

Sensory levels are mapped so that T4 corresponds to the nipple line, which is why chest tube and dermatome assessments are referenced to it. C6 covers the thumb and radial forearm, and T10 approximates the umbilicus.

Question 9Neuroanatomy and Physiology

A patient has uncal herniation compressing the right oculomotor nerve. Which finding is expected?

  1. Loss of the right corneal reflex
  2. Right eye turned inward with a small pupil
  3. Left ptosis with a normal pupil
  4. Right eye down and out, dilated pupil Correct answer.

Explanation

The oculomotor nerve supplies the medial rectus, superior rectus, inferior rectus, inferior oblique, and levator palpebrae, plus parasympathetic fibers to the pupil. When it fails, the unopposed lateral rectus and superior oblique pull the eye down and out, the lid droops, and the pupil becomes fixed and dilated.

Question 10Neuroanatomy and Physiology

The motor signs of Parkinson disease result primarily from loss of which neurotransmitter in the substantia nigra?

  1. Serotonin
  2. Dopamine Correct answer.
  3. Gamma-aminobutyric acid
  4. Acetylcholine

Explanation

Degeneration of dopaminergic neurons in the substantia nigra pars compacta depletes striatal dopamine and disturbs basal ganglia modulation of movement. The resulting imbalance leaves cholinergic activity relatively unopposed, which is why anticholinergic drugs can ease tremor.

Question 11Neuroanatomy and Physiology

Which cortical area, located in the posterior inferior frontal lobe of the dominant hemisphere, directs the motor production of speech?

  1. Arcuate fasciculus
  2. Wernicke area
  3. Angular gyrus
  4. Broca area Correct answer.

Explanation

Broca area programs the articulation and sequencing of speech, so damage produces nonfluent output with relatively preserved comprehension. Wernicke area in the posterior superior temporal lobe governs comprehension of language.

Question 12Neuroanatomy and Physiology

Which meningeal layer adheres directly to the surface of the brain and dips into the sulci?

  1. Falx cerebri
  2. Dura mater
  3. Arachnoid mater
  4. Pia mater Correct answer.

Explanation

The pia mater is the delicate innermost meningeal layer, closely applied to the cortex and following each sulcus and fissure. It is separated from the arachnoid by the CSF-filled subarachnoid space.

Question 13Neuroanatomy and Physiology

Which structure regulates body temperature, thirst, and hormone release from the anterior pituitary?

  1. Medulla oblongata
  2. Pineal gland
  3. Substantia nigra
  4. Hypothalamus Correct answer.

Explanation

The hypothalamus contains thermoregulatory and osmoregulatory centers and secretes releasing hormones that govern the anterior pituitary. It links the nervous and endocrine systems through the pituitary portal circulation.

Question 14Neuroanatomy and Physiology

Which information is carried by the spinothalamic tract?

  1. Voluntary motor commands to the ipsilateral limb
  2. Pain and temperature from the contralateral body Correct answer.
  3. Vibration and proprioception from the ipsilateral limb
  4. Fine touch and pressure from the ipsilateral face

Explanation

Nociceptive and thermal fibers synapse and cross within the spinal cord, then ascend in the contralateral spinothalamic tract to the thalamus. Vibration and proprioception travel instead in the dorsal columns, crossing only in the medulla.

Question 15Neuroanatomy and Physiology

Which cranial nerve provides the motor efferent limb of the gag reflex?

  1. Facial nerve (CN VII)
  2. Vagus nerve (CN X) Correct answer.
  3. Trigeminal nerve (CN V)
  4. Glossopharyngeal nerve (CN IX)

Explanation

Sensation from the posterior pharynx travels on the glossopharyngeal nerve, and the resulting pharyngeal constriction is carried by the vagus nerve. Testing the gag reflex therefore assesses both nerves together.

Question 16Neuroanatomy and Physiology

Which clinical finding is most consistent with a lesion of the right cerebellar hemisphere?

  1. Bilateral resting tremor of the hands
  2. Contralateral homonymous hemianopia
  3. Ipsilateral intention tremor and dysmetria Correct answer.
  4. Contralateral hemiparesis with hyperreflexia

Explanation

Cerebellar motor pathways decussate twice, so a hemispheric lesion produces incoordination on the same side, with dysmetria, intention tremor, and ataxia. Strength and reflexes remain relatively preserved because the corticospinal tract is spared.

Question 17Neuroanatomy and Physiology

Which value represents normal intracranial pressure in a resting adult?

  1. 5 to 15 mm Hg Correct answer.
  2. 26 to 35 mm Hg
  3. 16 to 25 mm Hg
  4. 0 to 2 mm Hg

Explanation

Normal intracranial pressure in adults is roughly 5 to 15 mm Hg, equivalent to about 10 to 20 cm of water. Sustained pressures above 20 mm Hg warrant intervention because of the risk of herniation and secondary ischemia.

Question 18Neuroanatomy and Physiology

Which structure is required for consolidating new declarative memories?

  1. Hippocampus Correct answer.
  2. Cerebellum
  3. Medulla oblongata
  4. Amygdala

Explanation

Bilateral hippocampal damage prevents the formation of new episodic and factual memories while remote memories and procedural skills remain intact. The hippocampus mediates consolidation rather than permanent storage of declarative memory.

Question 19Neuroanatomy and Physiology

Which structure carries cerebrospinal fluid from the third ventricle to the fourth ventricle?

  1. Foramen of Monro
  2. Central canal
  3. Cerebral aqueduct Correct answer.
  4. Foramina of Luschka

Explanation

The cerebral aqueduct of Sylvius passes through the midbrain and connects the third and fourth ventricles. Obstruction at this narrow channel causes noncommunicating hydrocephalus with dilation of the lateral and third ventricles.

Question 20Neuroanatomy and Physiology

In the pupillary light reflex, which structure carries the efferent limb that constricts the pupil?

  1. Sympathetic fibers from the cervical chain
  2. Optic nerve (CN II)
  3. Facial nerve (CN VII)
  4. Oculomotor nerve (CN III) Correct answer.

Explanation

Light detected by the retina travels on the optic nerve to the pretectal nucleus, which signals both Edinger-Westphal nuclei. Parasympathetic fibers traveling with the oculomotor nerve then constrict the pupil.

Question 21Neuroanatomy and Physiology

Which lobe contains the primary visual cortex?

  1. Parietal lobe, behind the central sulcus
  2. Occipital lobe, at the posterior pole Correct answer.
  3. Temporal lobe, along the lateral fissure
  4. Frontal lobe, in front of the central sulcus

Explanation

The primary visual cortex lies along the calcarine fissure at the occipital pole. A lesion of one optic radiation or of the occipital cortex produces a contralateral homonymous hemianopia.

Question 22Neuroanatomy and Physiology

The blood-brain barrier is formed chiefly by tight junctions between which cells?

  1. Oligodendrocytes
  2. Choroid plexus epithelial cells
  3. Capillary endothelial cells Correct answer.
  4. Astrocytic end-feet surrounding vessels

Explanation

Nonfenestrated cerebral capillary endothelial cells joined by tight junctions create the barrier that restricts paracellular movement of water-soluble solutes. Astrocytic end-feet and pericytes support and induce this barrier but do not compose its tight junctions.

Question 23Neuroanatomy and Physiology

Which function is mediated by the basal ganglia?

  1. Control of movement initiation Correct answer.
  2. Regulation of body fluid osmolality
  3. Consolidation of declarative memory
  4. Conscious perception of painful stimuli

Explanation

The caudate, putamen, globus pallidus, subthalamic nucleus, and substantia nigra modulate the initiation and scaling of voluntary movement through thalamocortical loops. Their dysfunction produces hypokinetic disorders such as Parkinson disease or hyperkinetic disorders such as Huntington disease.

Question 24Neuroanatomy and Physiology

A patient speaks fluently but uses meaningless words and cannot follow simple commands. Which deficit pattern matches a lesion of Wernicke area?

  1. Nonfluent speech with intact comprehension
  2. Impaired repetition with spared fluency
  3. Fluent speech with poor comprehension Correct answer.
  4. Right-sided face and arm weakness

Explanation

Wernicke area in the posterior superior temporal gyrus of the dominant hemisphere mediates language comprehension, so lesions produce fluent but empty or jargon speech with impaired understanding. Broca area lesions instead produce nonfluent output with comprehension largely preserved.

Question 25Neuroanatomy and Physiology

Which set of effects results from sympathetic nervous system activation?

  1. Miosis, tachycardia, and bronchoconstriction
  2. Miosis, bradycardia, and bronchoconstriction
  3. Mydriasis, tachycardia, and bronchodilation Correct answer.
  4. Mydriasis, bradycardia, and increased salivation

Explanation

Sympathetic discharge prepares the body for stress by contracting the iris dilator, raising heart rate, and relaxing bronchial smooth muscle. These effects are mediated largely by norepinephrine acting on alpha and beta receptors.

Question 26Neuroanatomy and Physiology

Which cranial nerve innervates the lateral rectus muscle and moves the eye laterally?

  1. Trochlear nerve (CN IV)
  2. Oculomotor nerve (CN III)
  3. Facial nerve (CN VII)
  4. Abducens nerve (CN VI) Correct answer.

Explanation

The abducens nerve supplies the lateral rectus, so a deficit leaves the eye turned inward at rest and limits abduction. CN III supplies most of the remaining extraocular muscles, CN IV supplies the superior oblique, and CN VII is not an extraocular motor nerve.

Question 27Neuroanatomy and Physiology

Which neurotransmitter is released at the neuromuscular junction to depolarize skeletal muscle?

  1. Acetylcholine Correct answer.
  2. gamma-Aminobutyric acid
  3. Dopamine
  4. Norepinephrine

Explanation

Somatic motor neurons release acetylcholine, which binds nicotinic receptors on the motor end plate and initiates muscle contraction. Dopamine, norepinephrine, and GABA serve other circuits and do not mediate the skeletal motor end plate.

Question 28Neuroanatomy and Physiology

Which structure is the principal relay station for sensory information ascending to the cerebral cortex, with the exception of smell?

  1. Hypothalamus
  2. Amygdala
  3. Thalamus Correct answer.
  4. Pons

Explanation

Every major ascending sensory pathway except olfaction synapses in the thalamus before projecting to its cortical area. The hypothalamus governs homeostasis, the pons relays between cerebrum and cerebellum, and the amygdala processes emotion.

Question 29Neuroanatomy and Physiology

Which artery supplies the medial surfaces of the frontal and parietal lobes, including the cortical leg area?

  1. Basilar artery
  2. Anterior cerebral artery Correct answer.
  3. Posterior cerebral artery
  4. Middle cerebral artery

Explanation

The anterior cerebral artery runs in the longitudinal fissure and supplies the medial convexity, so its occlusion characteristically causes contralateral leg weakness. The MCA supplies the lateral convexity, the PCA the occipital and inferomedial temporal regions, and the basilar artery the brainstem and posterior structures.

Question 30Neuroanatomy and Physiology

At which level do most corticospinal tract fibers cross the midline?

  1. Midbrain
  2. Cervical spinal cord
  3. Medulla Correct answer.
  4. Pons

Explanation

Roughly 85 to 90 percent of corticospinal fibers cross in the pyramidal decussation at the caudal medulla and descend as the lateral corticospinal tract. This crossing is why a unilateral cerebral lesion produces contralateral weakness.

Question 31Neuroanatomy and Physiology

A pituitary adenoma compressing the optic chiasm most typically produces which visual field defect?

  1. Left homonymous hemianopsia
  2. Bitemporal hemianopsia Correct answer.
  3. Binasal hemianopsia
  4. Right homonymous hemianopsia

Explanation

The chiasm contains the crossing fibers from the nasal retina of each eye, and those fibers subserve the temporal visual fields. Midline compression therefore removes both temporal fields, producing a bitemporal hemianopsia.

Question 32Neuroanatomy and Physiology

Which nerve carries the efferent limb of the corneal (blink) reflex?

  1. Trigeminal nerve
  2. Optic nerve
  3. Glossopharyngeal nerve
  4. Facial nerve Correct answer.

Explanation

The ophthalmic division of the trigeminal nerve senses the corneal stimulus, and the facial nerve drives the orbicularis oculi to close the lids. Testing this reflex therefore assesses CN V1 and CN VII together.

Question 33Neuroanatomy and Physiology

Which sensory modalities are carried in the dorsal columns of the spinal cord?

  1. Pain and temperature
  2. Crude touch and pressure
  3. Vibration and proprioception Correct answer.
  4. Motor commands to skeletal muscle

Explanation

The dorsal columns carry fine discriminative touch, vibration sense, and conscious proprioception, which synapse in the medulla and cross as the medial lemniscus. Pain and temperature travel instead in the spinothalamic tract.

Question 34Neuroanatomy and Physiology

Which function is most closely associated with the amygdala?

  1. Fear processing and emotional salience Correct answer.
  2. Regulation of the respiratory rhythm
  3. Coordination of voluntary limb movement
  4. Consolidation of procedural motor skills

Explanation

The amygdala links sensory input with emotional significance and generates fear-related autonomic and behavioral responses. Respiratory rhythm generation belongs to the brainstem, coordination to the cerebellum, and motor skill learning to the basal ganglia and cerebellum.

Question 35Neuroanatomy and Physiology

A patient's tongue deviates to the left when protruded. Which nerve is most likely affected?

  1. Left glossopharyngeal nerve
  2. Left trigeminal nerve
  3. Left hypoglossal nerve Correct answer.
  4. Right hypoglossal nerve

Explanation

The genioglossus pushes the tongue forward, so a lower motor neuron lesion causes the tongue to deviate toward the weak side. Deviation to the left therefore points to the left hypoglossal nerve.

Question 36Neuroanatomy and Physiology

Extensor posturing of all four limbs in response to a painful stimulus most reliably localizes the lesion to which level?

  1. Cerebral cortex
  2. Cervical spinal cord segments
  3. Internal capsule
  4. Midbrain or upper pons Correct answer.

Explanation

Decerebrate extensor posturing reflects damage between the red nucleus and the vestibular nuclei, releasing pontine extensor tone. Decorticate flexor posturing instead indicates a lesion above the red nucleus.

Question 37Neuroanatomy and Physiology

A slowly enlarging spinal cord tumor causes weakness, atrophy, and fasciculations confined to the right hand. Which structure is most likely compressed?

  1. Primary motor cortex
  2. Internal capsule
  3. Corticospinal tract
  4. Anterior horn cells Correct answer.

Explanation

Atrophy and fasciculations are lower motor neuron signs, and the lower motor neurons for the arm lie in the anterior horn and ventral root of the cervical cord. Corticospinal lesions instead produce upper motor neuron signs such as spasticity, hyperreflexia, and disuse weakness.

Question 38Neuroanatomy and Physiology

Occlusion of the left middle cerebral artery most typically produces which pattern of weakness?

  1. Bilateral lower extremity weakness
  2. Ipsilateral facial droop
  3. Contralateral leg weakness with arm sparing
  4. Contralateral face and arm weakness Correct answer.

Explanation

The middle cerebral artery supplies the lateral cortical convexity, where the face and arm occupy most of the homunculus, so infarction causes contralateral brachiofacial weakness. Leg-predominant weakness with arm sparing points instead to the anterior cerebral territory.

Question 39Neuroanatomy and Physiology

The Monro-Kellie doctrine is best summarized by which statement?

  1. Intracranial pressure decreases as brain volume rises
  2. One compartment must shrink when another expands Correct answer.
  3. Cerebral blood flow is independent of intracranial pressure
  4. CSF production varies directly with posture

Explanation

Because the adult skull is rigid, the combined volume of brain, blood, and cerebrospinal fluid is fixed, so growth of one component requires displacement of another. Once that compensation is exhausted, small added volumes cause steep rises in intracranial pressure.

Question 40Neuroanatomy and Physiology

A small demyelinating plaque destroys the right medial longitudinal fasciculus in the brainstem. Which gaze finding is most consistent with this lesion?

  1. Right eye fails to abduct on rightward gaze, and the eye rests turned inward and slightly down
  2. Left eye fails to adduct on rightward gaze, with nystagmus of the right eye
  3. Both eyes fail to elevate during attempted upward gaze, accompanied by lid retraction
  4. Right eye fails to adduct on leftward gaze, with nystagmus of the left eye Correct answer.

Explanation

The medial longitudinal fasciculus carries internuclear neurons from the abducens nucleus on one side to the contralateral oculomotor nucleus, so it mediates adduction of the eye opposite the abducens nucleus during conjugate horizontal gaze. A right MLF lesion therefore blocks adduction of the right eye when the patient looks left, while the left eye abducts with nystagmus (internuclear ophthalmoplegia).

Question 41Neurological Assessment and Monitoring

A patient opens the eyes spontaneously, is confused in conversation, and withdraws the arm from a painful stimulus. What Glasgow Coma Scale score should be documented?

  1. 11
  2. 12 Correct answer.
  3. 14
  4. 9

Explanation

Spontaneous eye opening scores 4, confused conversation scores 4, and withdrawal from pain scores 4, for a total of 12. The Glasgow Coma Scale sums three subscores: eye opening (1-4), verbal response (1-5), and best motor response (1-6).

Question 42Neurological Assessment and Monitoring

Which intracranial pressure range is generally considered normal for a resting adult?

  1. 16 to 25 mmHg
  2. 26 to 35 mmHg
  3. 5 to 15 mmHg Correct answer.
  4. 36 to 45 mmHg

Explanation

Normal adult intracranial pressure is approximately 5 to 15 mmHg, and sustained values above 20 mmHg are usually treated. Pressure within this range allows adequate cerebral perfusion while avoiding herniation risk.

Question 43Neurological Assessment and Monitoring

Which finding defines a positive Babinski sign in an adult?

  1. Loss of sharp sensation on the lateral sole
  2. Great toe dorsiflexes while other toes fan Correct answer.
  3. All toes plantar flex when the sole is stroked
  4. Rhythmic ankle clonus after passive dorsiflexion

Explanation

Stroking the lateral sole and across the ball of the foot normally causes all toes to plantar flex; great toe dorsiflexion with fanning of the other toes indicates an upper motor neuron lesion in an adult. The response is normal in infants younger than about 1 year.

Question 44Neurological Assessment and Monitoring

The afferent limb of the corneal reflex is carried by which cranial nerve?

  1. Facial nerve (CN VII)
  2. Optic nerve (CN II)
  3. Oculomotor nerve (CN III)
  4. Trigeminal nerve (CN V) Correct answer.

Explanation

Sensation from the cornea travels through the ophthalmic division of the trigeminal nerve, while the facial nerve supplies the orbicularis oculi that produces the blink. An absent corneal reflex suggests brainstem dysfunction and is a key finding in brain death testing.

Question 45Neurological Assessment and Monitoring

Which statement describes a muscle strength grade of 3/5?

  1. Full range of motion against gravity and resistance
  2. A palpable contraction with no visible movement
  3. Full range of motion with gravity eliminated
  4. Movement against gravity but not against resistance Correct answer.

Explanation

Grade 3 indicates active movement through the full range against gravity but inability to overcome added resistance. Grade 4 allows movement against gravity plus some resistance, and grade 5 is normal strength.

Question 46Neurological Assessment and Monitoring

A patient arouses only after vigorous, repeated painful stimulation and becomes unresponsive again as soon as the stimulus stops. How is this level of consciousness documented?

  1. Stupor Correct answer.
  2. Lethargy
  3. Coma
  4. Obtundation

Explanation

Stupor describes a state in which only strong or repeated stimuli produce arousal and the patient promptly returns to unresponsiveness. Coma, by contrast, is a complete absence of response to any stimulus.

Question 47Neurological Assessment and Monitoring

Which assessment finding is a classic sign of meningeal irritation?

  1. Great toe dorsiflexion on plantar stimulation
  2. Inability to stand with the eyes closed
  3. Pain on knee extension with the hip flexed Correct answer.
  4. Downward drift of the extended arm

Explanation

Kernig sign is hamstring pain and resistance when the knee is extended while the hip is flexed, and together with nuchal rigidity and Brudzinski sign it signals meningeal irritation. These signs accompany meningitis and subarachnoid hemorrhage.

Question 48Neurological Assessment and Monitoring

Which cranial nerve carries the efferent limb of the pupillary light reflex?

  1. Oculomotor nerve Correct answer.
  2. Trochlear nerve
  3. Abducens nerve
  4. Optic nerve

Explanation

Light sensed by the retina travels via the optic nerve, and the response is carried by parasympathetic fibers of the oculomotor nerve that constrict the pupil. Compression of the oculomotor nerve therefore produces a dilated, unreactive pupil.

Question 49Neurological Assessment and Monitoring

Cushing's triad, which signals rising intracranial pressure, consists of which findings?

  1. Hypotension with bradycardia and hyperthermia
  2. Hypotension, tachycardia, and shallow respirations
  3. Hypertension, tachycardia, and deep, rapid breathing
  4. Hypertension, bradycardia, irregular respirations Correct answer.

Explanation

Cushing's triad is systolic hypertension with a widened pulse pressure, bradycardia, and irregular respirations. It reflects cerebral ischemia triggering sympathetic outflow with a vagally mediated slowing of the heart rate and is a late, ominous sign of herniation.

Question 50Neurological Assessment and Monitoring

A patient's mean arterial pressure is 85 mmHg and the intracranial pressure is 18 mmHg. What is the cerebral perfusion pressure?

  1. 67 mmHg Correct answer.
  2. 37 mmHg
  3. 103 mmHg
  4. 85 mmHg

Explanation

Cerebral perfusion pressure equals mean arterial pressure minus intracranial pressure, so 85 minus 18 is 67 mmHg. A CPP of roughly 60 to 70 mmHg is generally targeted after traumatic brain injury.