Korsakoff Syndrome

Abstract

Abstract Korsakoff syndrome, originally known as Korsakoff's psychosis, is a mental disorder that is characterized by severe and irreversible memory impairments and confabulation behavior in the absence of intellectual decline or attention deficits (Zubaran, Fernandes, & Rodnight, 1997). The syndrome was first described by Sergei Korsakoff in the late nineteenth century, based on observations of brain‐lesioned patients with a history of chronic alcoholism. Korsakoff syndrome is associated with chronic alcohol abuse and malnutrition, resulting in a thiamine deficiency that presumably causes brain damage in the diencephalon, notably the mammillary bodies and the thalamus. Lesions in other brain areas, such as the frontal lobes, have also been associated with Korsakoff syndrome (Visser et al., 1999). The syndrome is classified in the Diagnostic and Statistical Manual of Mental Disorders (DSM‐IV‐TR; American Psychiatric Association, 2000) as alcohol‐induced persisting amnestic disorder, but Korsakoff syndrome has also been found in patients with chronic thiamine deficiency of nonalcoholic origin, such as anorexia, pregnancy, or dialysis. Typically, it is preceded by a confusional state with a sudden onset in combination with opthalmoplegia and stance and gait ataxia, known as Wernicke's disease or Wernicke's encephalopathy. Since the etiology of both Wernicke's disease and Korsakoff syndrome is the same, they are often taken together as the Wernicke‐Korsakoff syndrome or complex, with an estimated prevalence of approximately 1–2% in the general population (Zubaran et al., 1997).