📝 Step 5 — KMU Past Papers & Exam Learning

This section contains KMU-style past paper questions designed to strengthen conceptual understanding. Focus on understanding explanations rather than memorizing answers.

🎯 How to Study KMU Past Papers

• Read the question carefully.
• Think about the answer before looking.
• Read the explanation slowly.
• Understand the reasoning behind the correct answer.
• Revise difficult questions again.

MCQ 1

Question:
A patient develops weakness of the opposite hand after a small cortical lesion. The trunk muscles are relatively spared. Which feature best explains this pattern?

Options:
Bilateral cortical control of distal muscles
Large cortical control of skilled hand movement
Dominant vestibular control of finger muscles
Direct cerebellar supply to hand muscles
Segmental reflex control of cortical neurons

Correct Answer:
Large cortical control of skilled hand movement

Explanation:
The hand has a large motor cortical representation because it requires fine, skilled, fractionated movements. Therefore, cortical lesions commonly affect hand function prominently.

MCQ 2

Question:
A lesion affecting the medial surface of the precentral gyrus is most likely to produce weakness mainly in which region?

Options:
Opposite face
Opposite hand
Opposite lower limb
Same-side tongue
Same-side shoulder

Correct Answer:
Opposite lower limb

Explanation:
The lower limb area is represented medially in the motor homunculus. The face and upper limb are represented more laterally.

MCQ 3

Question:
A student can contract individual muscles but cannot organize a learned sequence of hand movements properly. Which cortical area is most likely involved?

Options:
Primary somatosensory cortex
Supplementary motor cortex
Primary auditory cortex
Visual association cortex
Vestibular cortical area

Correct Answer:
Supplementary motor cortex

Explanation:
The supplementary motor area helps organize learned, sequential, and bilateral motor activities. Damage may disturb motor planning despite preserved basic strength.

MCQ 4

Question:
During reaching for an object, visual information is used to prepare the direction and posture of the limb. Which cortical area has the strongest role in this preparation?

Options:
Premotor cortex
Primary visual cortex
Primary auditory cortex
Olfactory cortex
Primary gustatory cortex

Correct Answer:
Premotor cortex

Explanation:
The premotor cortex prepares movements guided by external sensory cues, especially visual guidance during reaching or positioning.

MCQ 5

Question:
A lesion in the dominant inferior frontal gyrus produces non-fluent speech with preserved basic muscle power of the tongue. Which function is mainly affected?

Options:
Auditory perception of sound
Motor planning of speech
Taste sensation from tongue
Reflex swallowing response
Visual recognition of letters

Correct Answer:
Motor planning of speech

Explanation:
Broca’s area is responsible for motor programming of speech. Weakness is not the primary problem; speech output planning is impaired.

MCQ 6

Question:
A patient has a small infarct involving the posterior limb of the internal capsule. Severe weakness occurs because this structure contains which arrangement?

Options:
Scattered motor fibers over a wide cortex
Compact descending motor fibers
Isolated sensory nuclei only
Peripheral motor nerve roots
Separated anterior horn cells

Correct Answer:
Compact descending motor fibers

Explanation:
Corticospinal and corticobulbar fibers are densely packed in the internal capsule, so a small lesion can produce marked motor deficit.

MCQ 7

Question:
A corticospinal tract lesion in the right cerebral peduncle is most likely to produce motor deficit on which side?

Options:
Right side above the lesion
Right side below the lesion
Left side of the body
Both sides equally
Only axial muscles bilaterally

Correct Answer:
Left side of the body

Explanation:
A lesion above the pyramidal decussation affects the opposite side because most corticospinal fibers cross in the lower medulla.

MCQ 8

Question:
A spinal cord hemisection damages the left lateral corticospinal tract below the pyramidal decussation. Which deficit is expected below the lesion?

Options:
Right-sided flaccid paralysis
Left-sided UMN weakness
Bilateral facial weakness
Loss of voluntary eye movement
Right-sided lower facial weakness

Correct Answer:
Left-sided UMN weakness

Explanation:
After medullary crossing, lateral corticospinal fibers descend on the same side of the spinal cord. Therefore, spinal cord lesions produce ipsilateral UMN weakness below the lesion.

MCQ 9

Question:
A patient loses fine independent finger movements but can still maintain basic standing posture. Which pathway is most selectively impaired?

Options:
Vestibulospinal pathway
Reticulospinal pathway
Lateral corticospinal pathway
Tectospinal pathway
Medial longitudinal fasciculus

Correct Answer:
Lateral corticospinal pathway

Explanation:
The lateral corticospinal tract is essential for skilled voluntary movement of distal limb muscles, especially fingers.

MCQ 10

Question:
A unilateral upper motor neuron lesion causes weakness of the lower face with relative sparing of the forehead. What is the best explanation?

Options:
Forehead muscles lack motor supply
Upper face receives bilateral cortical input
Lower face receives bilateral spinal input
Facial muscles are controlled by cerebellum
Trigeminal nerve supplies lower face movement

Correct Answer:
Upper face receives bilateral cortical input

Explanation:
Upper facial muscles receive bilateral corticobulbar input, so they are relatively spared in unilateral UMN facial lesions. The lower face has mainly contralateral cortical control.

MCQ 11

Question:
During voluntary elbow flexion, the antagonist muscle must be inhibited while the agonist contracts. Which spinal element mainly mediates this coordination?

Options:
Posterior column fibers
Spinal interneurons
Dorsal root ganglia
Muscle spindle capsules
Cerebellar Purkinje cells

Correct Answer:
Spinal interneurons

Explanation:
Corticospinal fibers often act through spinal interneurons, which coordinate agonist-antagonist activity during voluntary movement.

MCQ 12

Question:
During voluntary contraction, muscle spindles remain sensitive to stretch because of activity in which neurons?

Options:
Alpha motor neurons
Gamma motor neurons
Preganglionic autonomic neurons
Second-order sensory neurons
Postganglionic sympathetic neurons

Correct Answer:
Gamma motor neurons

Explanation:
Gamma motor neurons adjust intrafusal muscle fibers and maintain spindle sensitivity during contraction.

MCQ 13

Question:
A patient has increased tendon reflexes after a chronic corticospinal tract lesion. Which mechanism best explains this finding?

Options:
Reduced neuromuscular transmission
Loss of descending inhibitory control
Degeneration of muscle spindle endings
Failure of anterior horn cells
Block of peripheral nerve conduction

Correct Answer:
Loss of descending inhibitory control

Explanation:
UMN lesions remove descending regulation of spinal reflex circuits, making reflexes hyperexcitable.

MCQ 14

Question:
A patient develops spasticity after damage to the descending motor pathway. Which combination best describes this state?

Options:
Reduced tone with absent reflexes
Increased tone with brisk reflexes
Normal tone with absent power
Flaccid tone with fasciculations
Reduced reflexes with severe wasting

Correct Answer:
Increased tone with brisk reflexes

Explanation:
Spasticity is an UMN sign characterized by increased tone and exaggerated reflexes due to loss of descending inhibition.

MCQ 15

Question:
A patient with a corticospinal lesion shows extension of the great toe on plantar stimulation. Which normal control has been lost?

Options:
Primitive spinal reflex suppression
Peripheral sensory receptor activity
Neuromuscular junction release
Posterior column conduction
Cerebellar cortical inhibition

Correct Answer:
Primitive spinal reflex suppression

Explanation:
Babinski sign appears when corticospinal control over primitive plantar reflex patterns is lost.

MCQ 16

Question:
A descending tract helps maintain upright posture by facilitating antigravity extensor muscles. Which tract is most responsible?

Options:
Tectospinal tract
Rubrospinal tract
Vestibulospinal tract
Lateral corticospinal tract
Spinothalamic tract

Correct Answer:
Vestibulospinal tract

Explanation:
The vestibulospinal tract maintains balance and antigravity extensor tone, especially during standing and postural adjustment.

MCQ 17

Question:
A sudden sound causes reflex turning of the head toward the stimulus. Which descending pathway is most closely involved?

Options:
Anterior corticospinal tract
Tectospinal tract
Rubrospinal tract
Vestibulospinal tract
Lateral spinothalamic tract

Correct Answer:
Tectospinal tract

Explanation:
The tectospinal tract coordinates reflex head and neck movements in response to visual and auditory stimuli.

MCQ 18

Question:
A lesion above the red nucleus produces flexion of upper limbs and extension of lower limbs. Which pathway remains functionally active to explain the upper limb posture?

Options:
Rubrospinal pathway
Vestibulocochlear pathway
Dorsal column pathway
Spinocerebellar pathway
Optic radiation pathway

Correct Answer:
Rubrospinal pathway

Explanation:
In decorticate rigidity, the red nucleus remains active. Rubrospinal output facilitates upper limb flexor tone.

MCQ 19

Question:
A severe brainstem lesion interrupts red nucleus influence and leaves extensor pathways dominant. Which posture is expected?

Options:
Upper limb flexion with lower limb flexion
Upper limb flexion with lower limb extension
Extension of upper and lower limbs
Flaccidity of all four limbs
Isolated facial deviation

Correct Answer:
Extension of upper and lower limbs

Explanation:
Decerebrate rigidity occurs when rubrospinal flexor influence is lost and vestibulospinal/reticulospinal extensor activity dominates.

MCQ 20

Question:
A patient with extrapyramidal dysfunction has abnormal posture and tone but no complete paralysis. Which explanation best fits this finding?

Options:
Extrapyramidal pathways mainly regulate background motor control
Extrapyramidal pathways directly replace lower motor neurons
Extrapyramidal pathways carry conscious pain sensation
Extrapyramidal pathways supply neuromuscular junctions
Extrapyramidal pathways form dorsal root ganglia

Correct Answer:
Extrapyramidal pathways mainly regulate background motor control

Explanation:
The extrapyramidal system regulates posture, tone, balance, and automatic motor activity. Its dysfunction affects movement quality more than causing pure paralysis.

📌 Important Exam Strategy

KMU examinations often test integrated understanding rather than isolated facts. Focus on linking anatomy, embryology, histology, and clinical concepts when reviewing questions.

✅ Revision Tip

If you can explain the reason behind the correct answer without looking at notes, your concept is strong.