Involvement of cortical midline structures in the processing of autobiographical information

Helder F Araujo; Jonas Kaplan; Hanna Damasio; Antonio Damasio

doi:10.7717/peerj.481

Involvement of cortical midline structures in the processing of autobiographical information

PeerJ. 2014 Jul 22:2:e481. doi: 10.7717/peerj.481. eCollection 2014.

Authors

Helder F Araujo¹, Jonas Kaplan², Hanna Damasio², Antonio Damasio²

Affiliations

¹ Brain and Creativity Institute, University of Southern California , Los Angeles , USA ; Neuroscience Graduate Program, University of Southern California , Los Angeles , USA ; Graduate Program in Areas of Basic and Applied Biology, University of Porto , Porto , Portugal.
² Brain and Creativity Institute, University of Southern California , Los Angeles , USA.

Abstract

The term autobiographical self has been used to refer to a mental state that permits reflection on self-identity and personality and the answer to related questions (Damasio, 1998). It requires the retrieval and integrated assembly of memories of facts and events that define an individual's biography. The neural mechanisms behind this state have not been fully elucidated, but it has been suggested that cortical midline structures (CMSs) are critically involved in processing self-related information. To date, the investigation of the involvement of CMSs in autobiographical-self processes has largely focused on the comparison between self and other in relation to one domain of information, personality traits, and has yielded conflicting results. Here, we investigated how activity in CMSs varies with (1) the target of the information (self versus an acquaintance), (2) the domain of information (personality traits versus facts), and (3) differences across individuals regarding how descriptive and how important/relevant the information targeted by the questions was, and regarding the amount of memory retrieved in order to answer the questions. We used an fMRI block-design in which 19 participants answered questions about traits and biographic facts, in relation to themselves and a distant acquaintance. In addition, the participants rated the descriptiveness and importance of the information targeted by the questions, and estimated the amount of memory retrieved to answer the questions. Our results showed that CMSs were active for both facts and traits and for both self and other, and that the level of activity in the posteromedial cortices was generally higher for other than for self. Moreover, the activity in CMSs also varied with the amount of memory retrieved to answer the questions and with descriptiveness and importance of the information. These findings suggest that involvement of CMSs during the evaluation of information is not specific for self, and depends on varied factors related to memory retrieval prompted by the questions and to processes required to answer them.

Keywords: Autobiographical memory; Autobiographical self; Cortical midline structures; Medial prefrontal cortex; Posteromedial cortex; Self.

Grants and funding

This work was supported by a grant from the Mathers Foundation to AD & HD. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.