Belief and sign, true and false: the unique of false belief reasoning

P300 as a correlate of false beliefs and false statements

INTRODUCTION

This study investigates P300 as a component for false belief and false statement processing with and without a communicative context. The purpose is to understand why P300 has been shown to be commonly involved in false belief and lie processing.

METHODS

Participants were presented with a story in which the protagonist holds a true belief and makes a true statement of it (true belief), holds a false belief and makes a true statement (false belief), or holds a true belief and makes a false statement (false statement) while electroencephalograms were recorded.

RESULTS

In Experiment 1, featuring a solitary protagonist, stronger posterior P300 was shown in the false belief condition than the true belief and false statement condition. With the installation of a communicative context by including a second character listening to the protagonist, Experiment 2 showed enhanced frontal P300 in the false statement condition compared to the true belief and false belief condition. A late slow wave was more prominent in the false belief condition than in the other two conditions in Experiment 2.

CONCLUSION

The present results suggest a situation-dependent nature of P300. The signal captures the discrepancy between belief and reality more readily than that between belief and words under a noncommunicative context. It becomes more sensitive to the discrepancy between belief and words than that between belief and reality in a communicative situation with an audience, which makes any false statement practically a lie.

The neural and cognitive time course of intention reasoning: Electrophysiological evidence from ERPs

Intention is a typical mental state in the theory of mind. However, to date, there have been theoretical debates on the conceptual structure of intention. The neural and cognitive time course of intention reasoning remains unclear. The present event-related potential (ERP) study had two purposes: first, to investigate the neural correlates of intention reasoning based on a differentiated conceptual structure distinguishing desire and intention; second, to investigate the neural basis of intention reasoning for different agents. Thus, we compared the neural activity elicited by intention reasoning for self and for others when the intention matched or mismatched the desire of the agent. The results revealed that three ERP components distinguished among different types of intention reasoning. A negative-going ERP deflection with right frontal distribution between 400 and 500 ms might reflect the cognitive conflict involved in intention reasoning, a right frontal late positive component might be associated with the categorisation of agents, and a centro-parietal late slow wave might indicate the conceptual mental operations associated with decoupling mechanisms in intention processing. These findings implied the neural and cognitive time course of intention reasoning and provided neural evidence for the differentiated conception of intention.

Modulation of behavioral and brain responses to visual perspective taking by social rejection: Evidence from electrophysiology

Visual perspective taking (VPT) is crucial for reasoning about other people's mental states. To explore the modulation of behavioral and neural responses to visual perspective taking by social rejection, we firstly manipulated rejection using get-acquainted oral communication and a two-person visual perspective task, then explored how the experience of social rejection affected the behavioral and neural responses during the follow-up classical one-person visual perspective task. The subjective rating and behavior results showed that social rejection increased individuals' negative affect level and feelings of need-threat, decreased self-regulation and impulsive control. The event-related potentials (ERP) and standardized low resolution brain electromagnetic tomography (sLORETA) results mainly showed that the increased parietal late slow wave (LSW) showed greater activities in SPL and rTPJ after social rejection. Moreover, compared with making judgments from self-perspective, making judgments from other-perspective yielded later TP450 and greater late frontal wave (LFW). In addition, the left LFW of socially rejected group showed more positive amplitude for other-inconsistent condition than that for other-consistent condition. These results suggested that social rejection might decrease impulsive control behaviorally, as well as increase neural processing of perspective taking, including visual-spatial perspective taking (indexed by the LSW), calculating of the self and other perspectives (indexed by the TP450), and processing of others' visual perspectives (indexed by the LFW). Our findings provide powerful evidence on neural mechanism underlying how social rejection modulates visual perspective taking, and support the model of social monitoring system, in that socially rejected individuals motivate to attend more carefully to social cues, such as other people's perspective.