A 50-year-old man with chronic alcohol dependence was treated for an acute confusional state with ophthalmoplegia and ataxia. He improved, but three weeks later he cannot recall any new information, repeatedly asks the same questions, and gives detailed but clearly fabricated accounts of events he never experienced. The neuropsychiatric deficit that best explains his fabrications is:

• A Loss of remote autobiographical memory with preserved new learning
• B Impaired encoding of new memories with intact remote memory ✓
• C A formal thought disorder producing delusional misidentification
• D Fluctuating attention with visual hallucinations

Explanation

This is Korsakoff syndrome, the chronic phase of Wernicke-Korsakoff disease. Thiamine deficiency damages the mammillary bodies and dorsomedial thalamus, producing dense anterograde amnesia; patients fill the memory gap with confabulations without intent to deceive. Remote memory is relatively spared early, which distinguishes it from option A. There is no primary thought disorder and consciousness is clear, excluding options C and D.

Reference: Kaplan and Sadock's Synopsis of Psychiatry, 12th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.