Confabulation in schizophrenia: evidence of a new form?

This study is an attempt to demonstrate confabulation in schizophrenia. Twelve patients who met DSM-III-R criteria for schizophrenia were matched for age, sex and pre-morbid IQ with 12 volunteers, 9 of whom were normal healthy subjects, with the remainder being depressed patients. To elicit confabulation, subjects were asked to recall narratives. In addition, subjects were examined on a number of neuropsychological tests. Confabulation was defined as recall of information not present in the narrative. Variable amounts of confabulation were observed in all schizophrenics, while only one control subject confabulated. The content and structure of their productions differed from previously reported forms of confabulation in that schizophrenic patients spontaneously rearranged the original narratives to produce new ideas. The amount of confabulation was found to be related to difficulties in suppressing inappropriate responses (Hayling test) and formal thought disorder, but unrelated to understanding of the gist or moral of the narratives. Tentative mechanisms for the process of confabulation are proposed, based on specific difficulties with comprehension, response monitoring and response suppression.