Confabulation and memory in patients with Alzheimer's disease

Confabulation occurs in many brain diseases and concomitant with various cognitive disturbances. The purpose of the present study was to describe semantic features of confabulation and to investigate the relationship between these features and aspects of memory in Alzheimer's disease (AD). A group of 15 AD patients were asked questions aiming to evoke confabulations. The answers were analyzed with focus on semantic remoteness to the target answers into four different categories that made it possible to study the genesis of confabulation. Cognitive tests measuring episodic and semantic memory, priming as well as global cognitive functioning were performed, and the results were related to semantic features of confabulation. Results showed that semantic remoteness to the target answers was positively related to poor performance on Mini Mental State Examination but not to item recall, word fluency, or priming. It appears that difficulties with retrieval of recent autobiographical memories may have resulted in substitution of correct information with remote autobiographical memories, that is primary dysdeictic confabulations.