Confabulation is a memory disturbance in which a person confuses imagined scenarios with actual memories with no intent to deceive. Most cases of confabulation are the result of dementia, brain damage, aneurism or Wernicke-Korsakoff syndrome (thiamine deficiency due to alcoholism).

People who confabulate stories are often very confident in their memories even after being shown contradicting evidence. These stories can vary from slight truth alterations to completely unbelievable or bizarre tales. Even when the stories are completely false, the person appears coherent, consistent and relatively normal.

Confabulations are classified into one of two categories: provoked and spontaneous. A provoked confabulation is when a patient invents an untrue story in response to a question. These tend to be quite common among patients with amnesia or dementia. A spontaneous confabulation is a more rare occurrence and involves the telling of an untrue story with no apparent motivation.

Confabulations may also be classified as verbal or behavioral. Verbal confabulations are more common and involve only talking about false memories. Behavioral confabulations, on the other hand, occur when the patient acts on these faulty beliefs.

Confabulated memories almost always occur in one’s autobiographical memory — the memory system of an individual’s own life experiences which are brought to awareness in episodes or segments. While there are many hypotheses regarding the origins of confabulation, the most well-received theories point to neurological problems.

Studies have suggested that confabulation is specifically tied to a dysfunction in retrieval from long-term memory. For example, damage to the frontal lobe can cause these issues, making it hard to retrieve and evaluate memories. Ultimately, however, confabulations point to a very complicated memory process that can be thwarted at any point during the encoding, storage or recollection of a memory.

Example: You ask a demented patient if he remembers the last time he saw you, and he earnestly describes an imaginary prior meeting.