Disturbance of time orientation, attention, and verbal memory in amnesic patients with confabulation

ABSTRACT

Confabulation is often observed in amnesic patients after brain damage. However, evidence regarding the relationship between confabulation and other neuropsychological functions is scarce. In addition, previous studies have proposed two possibilities of the relationship between confabulation and false memory, in which patients with confabulation are likely to retrieve false memories, or confabulations are relatively independent of false memories. The present study investigated how confabulation is related to various cognitive functions, including orientation, attention, frontal lobe function, memory, and mental status, and to false memories, as assessed by the Deese–Roediger–Mcdermott (DRM) paradigm. Patients with organic amnesia participated, and confabulations were evaluated using the Confabulation Battery. Amnestic patients were classified into two groups: confabulating (CP) and nonconfabulating patients (NCP). The CP group was significantly impaired in time orientation, attention, and verbal memory, compared to the NCP group and age-matched healthy controls (HC). Results of the DRM paradigm revealed no significant difference in false memory retrieval induced by critical lures across CP, NCP, and HC groups. Confabulating responses in organic amnesia could be in part induced by disturbance of time consciousness and attention control in severe impairment of verbal memories, and confabulation and false memory could be modulated by different cognitive systems.

KEYWORDS:

• Confabulation
• amnesia
• orientation
• attention
• false memory

Acknowledgements

We thank Kosuke Kanemoto and Ryuta Kawashima for supplying test materials of the Confabulation Battery and Frontal Assessment Battery (FAB).

Additional information

Funding

This research was supported by a grant from the Japan Society for the Promotion of Science (JSPS) Next Program (LZ001) initiated by the Council for Science and Technology Policy (CSTP), JSPS KAKENHI [grant number 24530915], [grant number 26119512]; and The Naito Foundation. The authors declare no conflict of interest associated with this manuscript.