Involvement of cortical midline structures in the processing of autobiographical information

Commonalities and specificities between environmental navigation and autobiographical memory: A synthesis and a theoretical perspective

It has been proposed that declarative memory evolved from spatial navigation, with episodic memory having its roots in mechanisms of egocentric navigation and semantic memory in those of allocentric navigation; however, whether these brain networks actually overlap is still unclear. Using Activation Likelihood Estimation, we assessed the correspondence between brain correlates of spatial navigation (SN) and autobiographical memory (AM), further testing whether neural substrates of episodic memory (EAM) and egocentric navigation, and those of semantic memory (SAM) and map-like navigation, coincide. SN and AM commonly activated the parahippocampal gyrus and middle hippocampus, posterior cingulate cortex and right angular gyrus, but also involved distinct brain regions. Similarly, EAM and egocentric navigation, besides sharing a network involving the right angular gyrus, bilateral posterior cingulate and parahippocampal gyrus, activated distinct brain regions; no region was commonly activated by SAM and allocentric navigation. We discuss findings in the light of theories on the relation between navigation and memory, and propose a new theoretical perspective, which takes into account the dynamic nature of navigational processes.

Looking up to virtue: averting gaze facilitates moral construals via posteromedial activations

Witnessing exemplary actions triggers admiration, a positive emotion that can pertain to concrete skills, or move the onlooker beyond physical characteristics to appreciate the abstract, moral implications. Participants reacted to narratives depicting skilled or virtuous protagonists first during a videotaped interview then during functional magnetic resonance imaging (fMRI). We analyzed participants’ gaze aversion (an indicator of disengaging from the immediate environment) and cognitive construals (mentions of concrete characteristics vs abstract beliefs and values) during the interview, and relations to individuals’ subsequent neural activations. When participants averted their gaze, they were more likely to mention abstract construals, and both behaviors were more likely when reacting to virtue. Gaze aversion to virtue narratives predicted greater subsequent activation for those narratives in dorsal posterior cingulate cortex (dPCC), involved in visual attention control. The inferior-posterior posteromedial cortices (ipPMC), a default mode network hub involved in abstract thought, activated only to virtue, and activity level reflected individuals’ tendency to abstract construals. Critically, dPCC and ipPMC activity sequentially mediated the relationship between individuals’ gaze and abstract construal tendencies. No such relationships existed for reactions to skill, despite participants reporting equivalently strong positive emotion. In appreciating virtue, dPCC may support individuals in transcending the viewable context, facilitating ipPMC activity and moral construals.

Processing Narratives Concerning Protected Values: A Cross-Cultural Investigation of Neural Correlates

Narratives are an important component of culture and play a central role in transmitting social values. Little is known, however, about how the brain of a listener/reader processes narratives. A receiver's response to narration is influenced by the narrator's framing and appeal to values. Narratives that appeal to "protected values," including core personal, national, or religious values, may be particularly effective at influencing receivers. Protected values resist compromise and are tied with identity, affective value, moral decision-making, and other aspects of social cognition. Here, we investigated the neural mechanisms underlying reactions to protected values in narratives. During fMRI scanning, we presented 78 American, Chinese, and Iranian participants with real-life stories distilled from a corpus of over 20 million weblogs. Reading these stories engaged the posterior medial, medial prefrontal, and temporo-parietal cortices. When participants believed that the protagonist was appealing to a protected value, signal in these regions was increased compared with when no protected value was perceived, possibly reflecting the intensive and iterative search required to process this material. The effect strength also varied across groups, potentially reflecting cultural differences in the degree of concern for protected values.

Neural correlates of maintaining one's political beliefs in the face of counterevidence

People often discount evidence that contradicts their firmly held beliefs. However, little is known about the neural mechanisms that govern this behavior. We used neuroimaging to investigate the neural systems involved in maintaining belief in the face of counterevidence, presenting 40 liberals with arguments that contradicted their strongly held political and non-political views. Challenges to political beliefs produced increased activity in the default mode network-a set of interconnected structures associated with self-representation and disengagement from the external world. Trials with greater belief resistance showed increased response in the dorsomedial prefrontal cortex and decreased activity in the orbitofrontal cortex. We also found that participants who changed their minds more showed less BOLD signal in the insula and the amygdala when evaluating counterevidence. These results highlight the role of emotion in belief-change resistance and offer insight into the neural systems involved in belief maintenance, motivated reasoning, and related phenomena.

Influence of the cortical midline structures on moral emotion and motivation in moral decision-making

The present study aims to examine the relationship between the cortical midline structures (CMS), which have been regarded to be associated with selfhood, and moral decision making processes at the neural level. Traditional moral psychological studies have suggested the role of moral self as the moderator of moral cognition, so activity of moral self would present at the neural level. The present study examined the interaction between the CMS and other moral-related regions by conducting psycho-physiological interaction analysis of functional images acquired while 16 subjects were solving moral dilemmas. Furthermore, we performed Granger causality analysis to demonstrate the direction of influences between activities in the regions in moral decision-making. We first demonstrate there are significant positive interactions between two central CMS seed regions-i.e., the medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC)-and brain regions associated with moral functioning including the cerebellum, brainstem, midbrain, dorsolateral prefrontal cortex, orbitofrontal cortex and anterior insula (AI); on the other hand, the posterior insula (PI) showed significant negative interaction with the seed regions. Second, several significant Granger causality was found from CMS to insula regions particularly under the moral-personal condition. Furthermore, significant dominant influence from the AI to PI was reported. Moral psychological implications of these findings are discussed. The present study demonstrated the significant interaction and influence between the CMS and morality-related regions while subject were solving moral dilemmas. Given that, activity in the CMS is significantly involved in human moral functioning.

Neural correlates of different self domains

INTRODUCTION

The neural substrates of states devoted to processing self-related information ("self-related states") remain not fully elucidated. Besides the complexity of the problem, there is evidence suggesting that self-related states vary according to the information domain being considered. Here, we investigated brain correlates for self-related states concerning historical aspects of one's life (autobiographical self), and one's ongoing body status (core self). We focused on memory-related regions, body-related regions, CMSs (cortical midline structures), and ICs (insular cortices).

METHODS

This was a block-design fMRI study contrasting brain activity for core self (interoception and exteroception) and autobiographical self (personality traits and biographic facts) information domains. It involved 19 participants, who answered questions about each domain (four conditions).

RESULTS

All conditions appeared to engage the regions of interest. Nonetheless, autobiographical self compared with core self showed greater activity in memory-related regions (e.g., hippocampus), MPFC (medial prefrontal cortex), superior PMC (posteromedial cortex), and anterior ICs. Core self compared with autobiographical self was associated with greater activity in body-related regions (e.g., somatosensory cortices, and EBA [extrastriate body area]), superior PMC, and posterior ICs. In addition, (1) facts compared with traits showed greater activity in body-related regions, memory-related regions, MPFC, and PMC; (2) traits compared with facts were associated with greater activity in the posterior part of the anterior cingulate cortex; (3) interoception compared with exteroception was associated with greater activity in body-related regions (e.g. postcentral gyrus), memory-related regions, MPFC, inferior PMC and ICs; (4) exteroception compared with interoception showed greater activity in some body-related regions (e.g., premotor cortices and EBA) and superior PMC.

CONCLUSIONS

The results support the notion that the neural correlates of self-related states depend on the information domain. Those states seem distinguishable in terms of activity in memory-related and body-related regions, and activity in regions that have been associated with self processes (CMSs and the ICs).