Confabulations in alcoholic Korsakoff patients.

Besides forgetting, memory is also prone to distortions, errors and illusions. Confabulation is one type of memory distortion that may occur in cases of brain damage. Although confabulations are described anecdotally in patients with alcoholic Korsakoff syndrome (KS), there are few systematic investigations of the presence and nature of these types of false memories in KS. Moreover, it is unclear whether KS patients' confabulations evenly affect all types of memories, or whether certain memory domains are more susceptible. Our study attempted to clarify two questions: first, whether confabulations are a critical feature of the cognitive impairment associated with long-term KS in a large sample of patients (N=42). Second, we investigated which memory domain is most likely affected by confabulations in KS. To elicit confabulations, we used a Confabulation Interview containing questions from different memory domains. We found that KS patients overall confabulated more compared to a group of healthy subjects. Furthermore, we found that patients confabulated most within the episodic/autobiographical memory domain. Our results imply that besides pronounced memory deficits typically associated with KS, confabulation can also be regarded as a clinical feature of the disease. The preponderance of episodic confabulation obtained here by using a standardized test, confirms anecdotic reports that KS patients confabulate in everyday life mainly with respect to their personal past and present. Thus, for a detailed description of the memory profile of KS patients, the screening of confabulation tendencies may be a useful supplementary clinical tool.