AN62.1-6 | Cranial nerve nuclei & Cerebral hemispheres — Part 3

SELF-CHECK — Self-Check: Cerebral Hemispheres

Broca's aphasia (motor aphasia) results from damage to areas 44 and 45 in the left hemisphere. The patient's speech is:

A. Non-fluent (effortful, halting) but comprehension is relatively preserved

B. Fluent but incomprehensible (jargon, paraphasias)

C. Complete absence of speech with normal comprehension

D. Preserved speech but inability to repeat

Hemiballismus (violent flinging movements of one side of the body) results from damage to:

A. Caudate nucleus

B. Globus pallidus

C. Subthalamic nucleus (contralateral)

D. Putamen

A pure motor stroke affecting the face, arm, and leg on one side with no sensory loss is most likely a lacunar infarct in the:

A. Posterior limb of the internal capsule and VPL thalamus

B. Posterior limb of the internal capsule (corticospinal and corticobulbar fibres)

C. Anterior limb of the internal capsule

D. Genu of the internal capsule alone

CLINICAL PEARL

MCA Stroke — Most Common Stroke in India

Left MCA territory (dominant hemisphere) infarct causes the classic triad:
1. Right hemiplegia (arm > leg, face included — lateral motor cortex + internal capsule)
2. Broca's (expressive) aphasia or Wernicke's (receptive) aphasia depending on sub-territory
3. Right homonymous hemianopia (optic radiation involvement)

CT brain in acute MCA stroke:
• Early signs (<6h): hyperdense MCA sign (clot in vessel), loss of grey-white differentiation, sulcal effacement
• 24–72h: low-density wedge-shaped infarct in MCA territory

Indian thrombolysis reality: IV tPA (alteplase) within 4.5 hours is standard of care; mechanical thrombectomy (clot retrieval) within 24 hours for large vessel occlusion. Only 2–3% of Indian stroke patients reach hospital in time for thrombolysis — a major healthcare access challenge.