Confabulation

One of the Latin roots of the term confabulation is fabulari, which became our word fable. When the German neurologists Karl Bonhoeffer, Arnold Pick, and Carl Wernicke began using the term in the early 1900s, they applied it to false memory reports, little fables, created by their patients, who suffered from a syndrome that later came to known as Korsakoff's amnesia. When asked what they did yesterday, these patients do not remember, but will report events that either did not happen or happened long ago. The technical definition of confabulation the early neurologists coined has three components: (a) Confabulations are false, (b) confabulations are reports, and (c) confabulations are about memories.

During the remainder of the 20th century, however, the use of the term was gradually expanded to cover claims made by other types of patients, many of whom had no obvious memory problems, including patients who deny illness, split-brain patients (who have had their hemisphere surgically separated to prevent the spread of epileptic seizures), patients with misidentification disorders (who make false claims about the identities of people), and patients with schizophrenia, as well as children and normal adults in certain situations. Patients who deny that they are paralyzed have been claimed to confabulate when they provide reasons for why they cannot move (“My arthritis is bothering me,” “I'm tired [Page 184]of following your commands”). Another type of patient will deny blindness and attempt to answer questions about what he or she sees, producing what have been called confabulations (“It's too dark in here”). Misidentification patients have been said to confabulate when asked what the motives of the “impostor” are, or why someone would go through all the trouble to impersonate someone else (“Perhaps my father paid him to take care of me”). Similarly, when the left hemispheres of split-brain patients attempt to answer questions without the necessary information (which is contained in their right hemispheres), this has also been called a confabulation.

There are thus currently two schools of thought on the proper scope of the concept of confabulation: (a) those who remain true to the original sense and so believe that the term should only be applied to false memory reports and (b) those who believe that the term can be usefully applied to a broader range of disorders. This possible expansion of the concept forces several difficult questions. Has the concept expanded so much as to become meaningless? Do the new confabulation syndromes share anything significant with the classical memory cases? Minimally, some confabulation syndromes involve memory (Korsakoff's, aneurysm of the anterior communicating artery), whereas others involve perception (denial of paralysis or blindness, split-brain syndrome, misidentification disorders). This entry focuses on the broader concept of confabulation and includes a description of confabulations based on both memory and perception. It will also examine what is known about the neuropsychology of confabulation.