Neuroanatomy: disconnection syndromes: practice question

A Anatomy question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Anatomy · Neuroanatomy: disconnection syndromes

Sample item

After a left posterior cerebral artery infarct, a right-handed teacher has a right homonymous hemianopia. She speaks normally and can write a sentence from dictation, but cannot read what she has just written. Which additional structure is damaged?

AGenu of the corpus callosumBArcuate fasciculusCAnterior commissureDSplenium of the corpus callosum

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

D. Splenium of the corpus callosum

The left visual cortex is destroyed, so visual input from the intact right visual cortex must cross the splenium of the corpus callosum to reach the left angular gyrus. When the splenium is also damaged, reading is lost while writing is preserved, giving alexia without agraphia.

Option by option

A. Genu of the corpus callosum
The genu connects the frontal lobes and does not carry visual information.
B. Arcuate fasciculus
Arcuate fasciculus damage causes conduction aphasia with impaired repetition, not isolated alexia.
C. Anterior commissure
The anterior commissure links the temporal lobes and olfactory areas, not the occipital cortices.
D. Splenium of the corpus callosum (correct)
Correct. The splenium carries visual information from the right occipital cortex to the language areas of the left hemisphere.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Anatomy question

What is the answer to this Anatomy question?

The best answer is D, Splenium of the corpus callosum. The left visual cortex is destroyed, so visual input from the intact right visual cortex must cross the splenium of the corpus callosum to reach the left angular gyrus.

Why is "Genu of the corpus callosum" not the answer?

The genu connects the frontal lobes and does not carry visual information.

Why is "Arcuate fasciculus" not the answer?

Arcuate fasciculus damage causes conduction aphasia with impaired repetition, not isolated alexia.

Why is "Anterior commissure" not the answer?

The anterior commissure links the temporal lobes and olfactory areas, not the occipital cortices.

What concept does this question test?

It tests Neuroanatomy: disconnection syndromes in Anatomy. When the splenium is also damaged, reading is lost while writing is preserved, giving alexia without agraphia.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Neuroanatomy: disconnection syndromes?

Learn every nerve by its route, its muscles and what a lesion looks like at the bedside. That one habit answers a large share of questions. Then use the flashcards and the other Anatomy questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.