Confabulation Extending across Episodic, Personal, and General Semantic Memory

Abstract

This paper compares a patient, AB, who showed florid confabulation with two other patients, one of whom had bilateral frontal lesions, and the other bilateral temporal lobe pathology. AB' s confabulation followed a Wernicke episode, and she had a clinical diagnosis of an alcoholic Korsakoff syndrome, implying diencephalic pathology. However, cervical carcinoma was also found, and the persistence of her confabulation was attributed to metabolic or other non-metastatic complications of carcinoma, affecting cortical function. In the late stages of her illness, she also developed bilateral posterior parietal-occipital metastases. AB was assessed on three measures of confabulation-Dalla Barba' s 1993a Confabulation Battery, the Autobiographical Memory Interview, and an Informal Interview. She showed “spontaneous" confabulation extending across episodic, personal semantic, and general semantic memory. In this, she contrasted with the frontal lobe lesion patient, who showed confabulation only in personal semantic memory, and the temporal lobe lesion patient, who did notconfabulate. From an account of her confabulations given by her brother, as well as our own observations of her pattern of responses, three factors were identified as contributing to the confabulation- confusions in the context of memories, involving both time and place; a high rate of perseverations, particularly in semantic memory; and a tendency to respond indiscriminately to the immediate social and environmental context. It is concluded that frontal pathology and a disorder in contextmemory may be necessary, butnotsufficient, conditions for spontaneous confabulations to occur, and any theoretical description of confabulation may need to take account of a number of contributing factors.