Structure & function of the brain
A patient has had a stroke. They understand what others are saying, but their speech is slow, difficult, and broken. Which area of the brain is most likely affected?
A. Wernicke’s area
B. Broca’s area
C. Primary visual cortex
D. Primary sensory cortex
Broca’s area
Which statement about spinal nerves is correct?
A. Spinal nerves contain only sensory fibres
B. The dorsal root carries motor information
C. A spinal nerve is formed when the sensory and motor roots join
D. The ventral ramus supplies only the muscles of the back
C. A spinal nerve is formed when the sensory and motor roots join
Question:
A patient’s chest X-ray shows an enlarged cardiac silhouette. The image was taken while the patient was lying supine using a portable machine. What is the most likely explanation?
A. The patient definitely has cardiomegaly
B. The AP view has magnified the heart
C. The PA view has widened the mediastinum
D. The lungs are overexpanded
The AP view has magnified the heart
A neuron has one axon and many dendrites extending from its cell body. What type of neuron is it, and name one location where it may be found?
A multipolar neuron. It may be found in the ventral horn of the spinal cord as a motor neuron.
A patient has weakness and reduced sensation affecting the posterior thigh, lower leg, and foot. Damage to which plexus is most likely, and which spinal nerve levels contribute to it?
A. Cervical plexus — C1 to C4
B. Brachial plexus — C5 to T1
C. Lumbar plexus — L1 to L4
D. Sacral plexus — L4 to S3
Sacral plexus — L4 to S3
Following a stroke, a patient can feel touch on the right side of their body but cannot accurately identify where they were touched or distinguish between two nearby points. Which cortical area and lobe are most likely affected?
A. Left primary sensory cortex in the parietal lobe
B. Right primary motor cortex in the frontal lobe
C. Left primary visual cortex in the occipital lobe
D. Right premotor cortex in the frontal lobe
Left primary sensory cortex in the parietal lobe
Where is a lumbar puncture needle usually inserted?
A. Between C3 and C4
B. Between T1 and T2
C. Between L3 and L4
D. Between S1 and S2
Between L3 and L4
Why are at least two orthogonal X-ray views usually required when assessing a suspected joint dislocation?
One view may hide the displacement because structures overlap. Two views, usually front and side, confirm the direction and extent of the dislocation.
A person touches a sharp object and immediately withdraws their hand. Name the three functional classes of neurons involved in this reflex pathway and state the direction or role of each.
Question: Which connective tissue layer surrounds a bundle of axons called a fascicle?
A. Epineurium
B. Perineurium
C. Endoneurium
D. Myelin sheath
Perineurium
A child with cerebral palsy has increased muscle tone and weakness, mainly affecting the right arm and right leg. The child also has difficulty with fine motor tasks using the right hand. Which area of the brain was most likely injured?
Left primary motor cortex in the frontal lobe
A patient sustains a spinal cord injury and loses pain and temperature sensation below the lesion, but vibration, fine touch, and awareness of limb position remain intact. Which part of the spinal cord white matter is most likely damaged?
Lateral column
For each condition below, name the preferred imaging modality:
Suspected subarachnoid haemorrhage following a sudden thunderclap headache
Suspected meniscal tear in the knee
Suspected free fluid in the abdomen after trauma
CT scan
MRI
Ultrasound — FAST examination
A patient with multiple sclerosis develops muscle weakness, visual disturbances, and slowed nerve conduction. Which glial cell is primarily damaged, and what is its normal function?
Oligodendrocytes are damaged. They normally form the myelin sheath around axons in the CNS, allowing faster saltatory conduction of nerve impulses.
Question:
A patient suddenly experiences a rapid heart rate, dilated pupils, and reduced digestive activity after a frightening event. Which division of the nervous system is responsible, and where do its nerve fibres originate?
The sympathetic division of the autonomic nervous system. Its fibres originate from the thoracic and upper lumbar spinal cord, approximately T1–L2/L3.
Following a traumatic brain injury, a patient can move normally and understands instructions but has difficulty planning tasks, controlling impulses, solving problems, and organising daily activities. Which brain region is most likely affected?
The prefrontal cortex in the frontal lobe
A patient requires a lumbar puncture. The needle is inserted below the level where the spinal cord normally ends to reduce the risk of spinal cord injury. Name:
Why is MRI not usually the first choice for detecting bone fractures?
MRI measures signals mainly from hydrogen in water and fat. Cortical bone contains very little hydrogen, so it appears dark, and fractures are less clearly visualised than on X-ray or CT.
Which nerve fibre would conduct an action potential the fastest?
A. A thin, unmyelinated Group IV fibre
B. A thin, myelinated Group III fibre
C. A thick, myelinated Group I fibre
D. A thick, unmyelinated fibre
C. A thick, myelinated Group I fibre
Question: Which statement about spinal nerve roots is correct?
A. The posterior root carries motor information away from the CNS
B. The anterior root carries sensory information toward the CNS
C. The posterior root carries sensory information toward the CNS
D. Both roots contain only autonomic fibres
C.The posterior root carries sensory information toward the CNS
A patient has a lesion affecting the diencephalon. They develop impaired sensory relay, disrupted sleep–wake regulation, and reduced hormonal control through the pituitary gland. Name the three diencephalic structures most likely involved.
A patient presents with severe lower back pain following an L4–L5 disc herniation. They report numbness around the inner thighs and perineum, difficulty starting urination, and new weakness in both legs. What condition should be suspected, and why is it a medical emergency?
Cauda equina syndrome due to compression of multiple lumbosacral nerve roots. It is a medical emergency because delayed decompression can cause permanent bladder, bowel, sexual, sensory, and motor dysfunction.
How are axial and coronal CT images viewed in relation to the patient?
A patient with a demyelinating disorder has slowed nerve conduction, although the axons remain intact. Damage is greatest at the gaps between adjacent myelin segments. What are these gaps called, and why are they essential for rapid conduction?
They are the nodes of Ranvier. They contain a high concentration of voltage-gated ion channels, allowing the action potential to be regenerated and “jump” from node to node through saltatory conduction.
A child with ataxic cerebral palsy has an unsteady, wide-based gait, poor balance, and difficulty coordinating voluntary movements. Which area of the brain is most likely affected?
A. Cerebellum
B. Hypothalamus
C. Primary motor cortex
D. Medulla oblongata
Cerebellum