Neurodegenerative Diseases USMLE Step 1 Practice Question
A 49-year-old man with alcohol use disorder presents with confusion, gait instability, and horizontal nystagmus. Vital signs show BP 128/76, HR 92, RR 16, Temp 37.2°C, SpO2 98%. Thiamine level is low at 28 nmol/L. After thiamine supplementation, his nystagmus resolves, but severe anterograde amnesia and confabulation persist. He denies recent head trauma. Which structure's damage is most associated with his permanent memory impairment?
Answer choices
- AOccipital cortex
- BSubthalamic nucleus
- CMammillary bodiesCorrect answer
- DSubstantia nigra
- ECerebellar hemisphere
- FMediodorsal thalamic nucleus
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