Korsakoff syndrome is a brain disorder caused by severe vitamin B1 (thiamine) deficiency, often linked to long-term alcohol misuse, but it can also result from malnutrition or other medical conditions. It primarily affects memory, causing severe gaps in recall, difficulty forming new memories, and sometimes confabulation (unintentionally making up stories to fill in memory gaps). Unlike other dementias, Korsakoff syndrome is not always progressive—if caught early and treated with proper nutritio