Summary

Confabulation is a mysterious adjunct of amnesia. It remains unexplained why some patients invent untrue stories in response to questions (provoked confabulations) or even spontaneously with no apparent motivation (spontaneous confabulations). Hypothesized mechanisms range from a desire to fill gaps in memory to a loss of the temporal context in memory. We examined the mechanisms of confabulations in 16 amnesic patients. Patients were classified as spontaneous confabulators if they ever acted according to their confabula-tions. Provoked confabulations were measured as the number of intrusions in a verbal learning test. We found a double dissociation between the two types of confabulations, indicat-ing that they represent different disorders rather than different degrees of the same disorder. Confabulating patients did not show an increased tendency to fill gaps in memory a