Exam 1 practice questions

Which statement BEST describes communication between M1 and S1?

Information flows reciprocally between M1 and S1.

Where does the superior cerebellar peduncle MAINLY decussate?

Caudal midbrain

The cerebellar vermis primarily projects to which deep cerebellar nucleus?

Fastigial nucleus

How many pairs of cranial nerves have attachments to the brainstem?

9 pairs

Which cranial nerves have attachments at or near the brainstem

CN V and VI

Which neurotransmitter does the parallel fiber release?

Glutamate/aspartate

Which neuron in the cerebral cortex PRIMARILY exerts the efferent function?

Pyramidal cell

Which venous sinus is located in the falx cerebelli?

Occipital sinus

A lesion damages projection fibers connecting the cerebral cortex with subcortical structures. Which white-matter structure is MOST likely involved?

Internal capsule

A patient can speak fluently but meaninglessly and cannot follow directions. Which Brodmann area is MOST likely injured?

Wernicke's area, Brodmann area 22

Most pontocerebellar fibers enter the cerebellum through which peduncle?

Middle cerebellar peduncle

Which fissure/sulcus is indicated by "8"?

Left lateral sulcus

Which cerebral lobe has been surgically resected to control epilepsy, as shown in the MRI?

Right temporal lobe

Which type of hematoma in the cranium is shown?

Epidural hematoma

Where are the reticular formation nuclei located?

Tegmental brainstem

The primary motor cortex is located in which Brodmann area?

Brodmann area 4

Which cerebellar artery will be compromised directly due to the indicated vertebral artery stroke?

Right PICA

Which motor nucleus receives predominantly contralateral corticobulbar input?

Lower facial nucleus

Which glial cell is directly affected by demyelination in multiple sclerosis?

Oligodendrocyte

Obstruction of the cerebral aqueduct would MOST directly cause enlargement of which ventricles?

Lateral and third ventricles

Which basal nucleus is located in the diencephalon?

Subthalamic nucleus

Which cerebellar cortical neuron uses glutamate as its neurotransmitter?

Granule cell

A patient has a brain tumor in the indicated location. Which component is MOST likely impaired?

Right parietal lobe

A roofer briefly loses consciousness, feels well, then suddenly loses consciousness again. What emergency should be suspected?

Epidural hematoma due to disruption of the middle meningeal artery

Based only on the cortical region involved in the herniation, which function is MOST likely impaired?

Language

A right PCA stroke damages the right thalamus. Which sensory finding is MOST likely?

Left-sided body sensory loss

A focal injury to the left postcentral gyrus would MOST likely cause what finding?

Right body paresthesia

A patient has right upper-limb and trunk paresthesia and weakness. Which artery is MOST likely impaired?

Left MCA

Irritation of the dura mater in which cranial region is MOST likely to produce referred pain to the upper cervical region?

Posterior cranial fossa

A lesion primarily involving the vestibulocerebellum would MOST likely produce which finding?

Truncal instability with impaired balance and eye-movement control

Which part of the internal capsule primarily contains corticobulbar fibers?

Genu

Most output from the deep cerebellar nuclei leaves the cerebellum through which peduncle?

Superior cerebellar peduncle

Which neurotransmitter does the Purkinje cell release, and what is its function?

GABA, inhibitory

Climbing fibers arising from the inferior olivary nucleus project primarily to which structures?

Contralateral deep cerebellar nuclei and Purkinje cells

A stroke impairing the inferior olivary nucleus would compromise which afferent fibers to the cerebellar cortex?

Climbing fibers

CSF is primarily returned to venous circulation through arachnoid granulations projecting into which dural sinus?

Superior sagittal sinus

Which prefrontal cortical region is most strongly associated with executive functions such as working memory, planning, and goal-directed behavioral control?

Left dorsolateral prefrontal cortex

Which brainstem region contains many cranial nerve nuclei and ascending sensory pathways?

Tegmentum

Which cranial nerve has nuclei located throughout the brainstem and proximal spinal cord?

CN V

Which cortical layers primarily provide efferent projections to subcortical structures?

Layers V and VI

Which brain structures are separated by the transverse fissure?

Occipital lobe and cerebellum

A patient leaves food on the left side of the plate after a stroke. Which cerebral lobe is MOST likely injured?

Right parietal lobe

Which brain structure serves as a major integrative center for autonomic nervous system regulation?

Hypothalamus

Where is the supplementary motor area primarily located?

Superior and medial portion of Brodmann area 6

In which cerebral lobe is the primary somatosensory cortex (S1) located?

Parietal lobe

Which secondary brain vesicle develops from the prosencephalon?

Diencephalon

The primary gustatory cortex is located primarily in which cerebral lobe?

Insular lobe

What is the general organization of cranial nerve nuclei in the brainstem?

Motor medial; sensory lateral

Which neocortical layer primarily receives sensory input from the thalamus?

Layer IV

Which cortical region is most strongly associated with executive functions such as planning, working memory, and cognitive control?

Left dorsolateral prefrontal cortex

Which glial cell forms the myelin sheath around axons in the CNS?

Oligodendrocytes

A patient with a left MCA stroke speaks fluently, but speech is meaningless and verbal comprehension is impaired. Which structure is most likely impaired?

Wernicke's area

A lesion involving the right-hemisphere homolog of Broca's area (BA 44/45) would MOST likely cause what communication deficit?

Difficulty expressing the emotional tone (prosody) of speech

What are the three major primary developmental vesicles of the brain?

Prosencephalon, mesencephalon, and rhombencephalon

What are the two secondary vesicles of the forebrain?

Telencephalon and diencephalon

Which secondary vesicle develops into the cerebral hemispheres?

Telencephalon

Which secondary vesicle contains the thalamus and hypothalamus?

Diencephalon

A patient has weakness of the right hand. Which cerebral hemisphere would you examine first?

Left cerebral hemisphere

Is the hand representation in M1 relatively medial or lateral to the lower-limb representation?

Lateral

A lesion involving the medial M1 would more strongly affect the lower limb or face?

Lower limb

A patient has difficulty processing the emotional tone of speech. Which hemisphere would you suspect?

Right hemisphere

Which cortical layer receives major input from the thalamus?

Layer IV

Which cortical layers provide major output to subcortical structures?

Layers V and VI

What is the major excitatory projection neuron of the neocortex?

Pyramidal cell

Is "one M1 column = one muscle" an accurate model?

No. M1 columns are better understood as networks that can represent coordinated movements/multiple muscles rather than one muscle each.

Where is M1 located?

Frontal lobe, precentral gyrus, Brodmann area 4

Where is S1 located?

Parietal lobe, postcentral gyrus, Brodmann areas 3, 1, and 2

Where is A1 located?

Temporal lobe, Brodmann area 41

Where is V1 located?

Occipital lobe, Brodmann area 17

Where is G1 (primary gustatory cortex) located?

Insular lobe

What types of communicating fibers form circuitry among cerebral cortices and other subcortical structures?

Association, commissural, and projection fibers

Which anatomic landmarks divide the cerebral cortex into different lobes?

Major sulci/fissures, especially the central sulcus, lateral sulcus, and parieto-occipital sulcus

Where is an action potential commonly initiated in a neuron?

Axon hillock/initial segment

A protein moves from the soma toward the axon terminal. Is this anterograde or retrograde transport, and which motor protein is used?

Anterograde transport; kinesin

Which glial cell forms myelin in the CNS, and which forms myelin in the PNS?

CNS: oligodendrocytes; PNS: Schwann cells

A virus enters an axon terminal and travels toward the soma. What type of axonal transport could it use?

Retrograde transport; dynein

What type of cerebral white-matter fibers pass through the internal capsule?

Projection fibers

What is the relationship between the corona radiata and internal capsule?

The corona radiata contains projection fibers that converge into the internal capsule.

What are the three major parts of the internal capsule?

Anterior limb, genu, and posterior limb

What structures border the anterior limb of the internal capsule?

Head of caudate medially and lentiform nucleus laterally

What structures border the posterior limb of the internal capsule?

Thalamus medially and lentiform nucleus laterally

Patient A: After a right frontal stroke, the eyes are deviated to the right. Which cortical area is likely affected?

Right frontal eye field, Brodmann area 8

Patient A: Why do the eyes deviate toward the lesion after a frontal eye field stroke?

Loss of the affected frontal eye field's drive to look contralaterally leaves the intact hemisphere unopposed, causing gaze toward the lesion.

Patient B: After a right parietal stroke, the patient ignores food on the left side of the plate. Which major function is impaired?

Spatial attention

Patient B: Which side of space is neglected?

Left side of space

A stroke around the left inferior frontal lobe causes nonfluent speech. Which Brodmann areas are affected and what type of aphasia occurs?

Broca's area, BA 44 and 45; expressive/nonfluent aphasia

Which cranial nerve nuclei are associated with the midbrain?

CN III, IV, and V

Which cranial nerve nuclei are associated with the pons?

CN V, VI, VII, and VIII

Where are the nuclei of CN V distributed?

From approximately the C2 spinal cord level through the brainstem to the midbrain

What is the basilar brainstem primarily associated with?

Descending tracts

What is the tegmentum primarily associated with?

Ascending and descending tracts and the reticular formation

What is the tectum primarily associated with?

Midbrain; superior colliculus for eye movement and inferior colliculus for hearing

Trace the corticopontocerebellar pathway.

Cerebral cortex → corticopontine fibers → pontine nuclei → decussate in the basilar pons → middle cerebellar peduncle → contralateral cerebellar cortex

Where does the sensory decussation occur?

Caudal medulla, in the tegmentum

Where does the motor decussation occur?

Caudal medulla, in the pyramids

What are the major horizontal and vertical gaze centers?

Horizontal gaze: PPRF; vertical gaze: rostral midbrain/pretectal region

Which peduncle carries pontocerebellar fibers?

Middle cerebellar peduncle

Where does the superior cerebellar peduncle decussate?

Caudal midbrain

What are the three structural lobes of the cerebellum?

Anterior, posterior, and flocculonodular lobes

What are the three functional divisions of the cerebellum?

Cerebrocerebellum, spinocerebellum, and vestibulocerebellum