What are confabulators' memories made of? A study of subjective and objective measures of recollection in confabulation.

Confabulating patients claim to remember events that had not actually happened, suggesting a vivid subjective experience of false memories. The present study was aimed at examining the nature of subjective experience of retrieval in confabulators and its relation to the objective ability to recollect qualitative aspects of the original episode. In Experiment 1, 5 confabulators, 7 non-confabulating patients, and 12 control subjects studied words under shallow and deep encoding conditions and underwent a Remember (R)/Know (K) recognition task [Tulving, E. (1985). Memory and consciousness. Canadian Psychology, 26, 1-12]. For recognized words, they additionally indicated two qualitative features of the encoding context. Whereas subjective (i.e. R responses) and objective (i.e. source) measures of recollection were associated in normal controls and non-confabulating patients, they were dissociated in confabulators. In Experiment 2, participants explained the content of their R responses. We found that confabulators' recollections mainly included autobiographical information related to test items, but not to the study encounter. We conclude that remembering states in confabulators may be linked to a deficit in inhibiting irrelevant memories triggered by test items during retrieval attempts.