In the Papez circuit, axons travelling in the mammillothalamic tract of Vicq d'Azyr originate from which structure and terminate in which target?

• A Hippocampal formation to the anterior nucleus of the thalamus directly
• B Cingulate gyrus to the entorhinal cortex
• C Mammillary bodies to the anterior nucleus of the thalamus ✓
• D Anterior nucleus of the thalamus to the mammillary bodies

Explanation

The Papez circuit runs: hippocampal formation, fornix, mammillary bodies, mammillothalamic tract, anterior thalamic nucleus, cingulate gyrus via the thalamocingulate radiation, then back through the cingulum to the entorhinal cortex and hippocampus. The mammillothalamic tract specifically links the mammillary bodies to the anterior thalamic nucleus. The hippocampus reaches the mammillary bodies via the fornix, not directly to the thalamus, which eliminates option A.

Reference: Snell's Clinical Neuroanatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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