Confabulation behavior and false memories in Korsakoff's syndrome: role of source memory and executive functioning.

Abstract

AIMS: Confabulation behavior is common in patients with Korsakoff's syndrome. A distinction can be made between spontaneous and provoked confabulations, which may have different underlying cognitive mechanisms. Provoked confabulations may be related to intrusions on memory tests, whereas spontaneous confabulations may be due to executive dysfunction or a source memory deficit. METHODS: In 19 chronic Korsakoff patients, spontaneous confabulations were quantified by third-party rating (Likert scale). Provoked confabulations were assessed using the Dalla Barba Confabulation Battery. Furthermore, assessment of executive function was performed using an extensive neuropsychological battery. False memories (i.e. intrusions) and source memory were measured using twoparallelversions of a word-list learning paradigm (a modification of the Rey Auditory Verbal Learning Test). RESULTS: There were deficits in source memory, in which patients incorrectly assigned previously learned words to an incorrect word list. Also, Korsakoff patients had extensive executive deficits, but no relationship between the severity of these deficits and the severity of confabulation or intrusions on a memory task was found. CONCLUSION: The present findings provide evidence for a dissociation between spontaneous confabulation, provoked confabulation and false memories.