Which vitamin deficiency is associated with Wernicke-Korsakoff syndrome?

Wernicke-Korsakoff syndrome is a neurocognitive disorder primarily linked to thiamine (vitamin B1) deficiency. This condition is commonly seen in individuals with chronic alcoholism, as alcohol consumption can impair thiamine absorption and utilization.

The syndrome has two distinct phases: Wernicke's encephalopathy, which presents with confusion, ophthalmoplegia (ocular muscle paralysis), and ataxia (lack of coordination), and Korsakoff syndrome, which is characterized by memory deficits and confabulation (making up stories to fill memory gaps). The link between thiamine deficiency and these neurological manifestations underscores the critical role of thiamine in neuronal function and metabolism.

The other vitamins mentioned have different roles in the body and are not associated with Wernicke-Korsakoff syndrome. Vitamin C is vital for collagen synthesis and antioxidant protection, vitamin B12 is crucial for red blood cell formation and neurological function, and riboflavin is involved in energy production and metabolism. None of these conditions relate to the specific symptoms or underlying mechanisms that define Wernicke-Korsakoff syndrome. Therefore, thiamine is the vitamin whose deficiency is directly implicated in this particular syndrome.