Distinct neural correlates underlying pretense and false belief reasoning: evidence from ERPs

Recursive structures modulate the electrophysiological correlates of visual perspective taking

An increasing number of studies have focused on the neural basis of complex mental inferences, which requires an understanding of the recursive nature of thought; however, the precise electrophysiological response to a recursive structure remains unclear. The present event-related potential (ERP) study investigated the recursive structure effect on the neural correlates of visual perspective taking by modifying a third-person visual perspective-taking task. Participants were required to determine how many dots in the presented scenes could be seen from the cued perspective, including the perspectives in the self, other, and recursive (one avatar's belief of another avatar) conditions. The ERP results showed that the N100 and P200 components specific to the recursive-perspective condition showed greater attentional allocation; the N200 component increased in the recursive condition and was related to the conflict process; and larger late slow waves were found in the other- and recursive-perspective conditions compared with those in the self-perspective condition, which reflected the decoupling mechanism. The results suggested that high-order perspective taking requires more attentional resources and conflict processing for further decoupling from the self-perspective.

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.

An Electrocortical Measure Associated with Metarepresentation Mediates the Relationship between Autism Symptoms and Theory of Mind

Impairments in theory of mind (ToM) - long considered common among individuals with autism spectrum disorder (ASD) - are in fact highly heterogeneous across this population. While such heterogeneity should be reflected in differential recruitment of neural mechanisms during ToM reasoning, no research has yet uncovered a mechanism that explains these individual differences. In this study, 78 (48 ASD) adolescents viewed ToM vignettes and made mental state inferences about characters' behavior while participant electrophysiology was concurrently recorded. Two candidate event-related potentials (ERPs) - the Late Positive Complex (LPC) and the Late Slow Wave (LSW) - were successfully elicited. LPC scores correlated positively with ToM accuracy and negatively with ASD symptom severity. Notably, the LPC partially mediated the relationship between ASD symptoms and ToM accuracy, suggesting this ERP component, thought to represent cognitive metarepresentation, may help explain differences in ToM performance in some individuals with ASD.

The Dynamic Differences between Self- and Other-Oriented Mental Inferences: An ERP Study on a False-Belief Task

Theory of mind (ToM) refers to the ability to infer others' mental states. In our everyday lives, we need to interact constantly and appropriately with others. Not only is ToM involved in understanding others' mental states (other-oriented mental inferences), but it also helps to keep our own mental states (self-oriented mental inferences). In this study, we designed a false-belief task using event-related potential (ERP) measures to investigate the dynamic differences between the two types of mental inferences. In the false-belief task, participants were prompted with a cue to attribute a belief to either themselves (self-oriented) or another person (other-oriented). Results showed that other-oriented false-belief attribution elicited a larger late positive component (LPC; 320~440 ms post-cue onset) than the one elicited by self-oriented attribution at bilateral parieto-occipital electrodes, and also a larger late negative component (LNC; 380~500 ms post-cue onset) at frontal-central electrodes. In addition, the difference in amplitude of LPC between the two types of false-belief attribution was positively correlated with self-reported autistic traits measured by the Autism Spectrum Quotient (AQ). Based on prior literature, we propose that the LPC and LNC reflect the processes of self-other distinction and conflict control, respectively. Moreover, the difficulty in distinguishing other from the self is related to one's degree of autistic traits.

Electrophysiological dynamics of false belief understanding and complementation syntax in school-aged children: Oscillatory brain activity and event-related potentials

A large body of research in developmental psychology has been devoted to the ongoing debate over which aspects of language are fundamental to false belief understanding (FBU). A key proposal from de Villiers and colleagues proposes the essential role of complementation syntax in FBU development. The current study, using scalp electroencephalography (EEG), addressed one opposing hypothesis purporting that complementation is redundant to FBU by characterizing the electrophysiological correlates of FBU and complementation syntax in school-age children. Time-frequency decomposition showed robust parieto-occipital low beta (12-16 Hz) power reduction in the belief versus complementation conditions. This divergence was also supported by event-related potentials (ERPs), with parieto-occipital late slow waves around 600 to 900 ms distinguishing belief and complementation conditions. The false belief condition generated the lowest behavioral response accuracy, suggesting that it is the most challenging condition. Together, the current findings provide evidence showing that complementation is not redundant to FBU.

Adolescents are delayed at inferring complex social intentions in others, but not basic (false) beliefs: An eye-movement investigation

Most developmental research on Theory of Mind (ToM)—our ability to infer the beliefs, intentions, and desires of others—has focused on the preschool years. This is unsurprising as it was previously thought that ToM skills are developed between the ages of 2 and 7 years. Over the last couple of decades however, studies have provided evidence for significant structural and functional changes in the brain areas involved in ToM (the “social brain”) not only during childhood but also during adolescence. Importantly, some of these findings suggest that the use of ToM shows a prolonged development through middle childhood and adolescence. Although evidence from previous studies suggests a protracted development of ToM, the factors that constrain performance during middle childhood and adolescence are only just beginning to be explored. In this article, we report two visual-world eye-tracking studies that focus on the timecourse of predictive inferences. We establish that when the complexity of ToM inferences are at a level which is comparable with standard change-of-location false-belief tasks, then adolescents and adults generate predictions for other agents’ behaviour in the same timecourse. However, when inferences are socially more complex, requiring inferences about higher order mental states, adolescents generate predictive gaze bias at a marked delay relative to adults. Importantly, our results demonstrate that these developmental differences go beyond differences in executive functions (inhibitory control or working memory) and point to distinct expectations between groups and greater uncertainty when predicting actions based on conflicting desires.

The neural basis of belief-attribution across the lifespan: False-belief reasoning and the N400 effect

The current study examined how social cognition – specifically, belief-state processing – changes across the lifespan, using a large sample (N = 309) of participants aged 10–86 years. Participants completed an event-related brain potential study in which they listened to stories involving a character who held either a true- or false-belief about the location of an object, and then acted in a manner consistent or inconsistent to this belief-state. Analysis of the N400 revealed that when the character held a true-belief, inconsistent outcomes led to a more negative-going N400 waveform than consistent outcomes. In contrast, when the character held a false-belief, consistent outcomes led to a more negative-going N400 waveform than inconsistent outcomes, indicating that participants interpreted the character's actions according to their own more complete knowledge of reality. Importantly, this egocentric bias was not modulated by age in an early time window (200–400 msec post-stimulus onset), meaning that initial processing is grounded in reality, irrespective of age. However, this egocentric effect was correlated with age in a later time window (400–600 msec post-stimulus onset), as older adults continued to consider the story events according to their own knowledge of reality, but younger participants had now switched to accommodate the character's perspective. In a final 600–1000 msec time window, this age modulation was no longer present. Interestingly, results suggested that this extended egocentric processing in older adults was not the result of domain-general cognitive declines, as no significant relationship was found with executive functioning (inhibitory control and working memory).

Age of avatar modulates the altercentric bias in a visual perspective-taking task: ERP and behavioral evidence

Despite being able to rapidly and accurately infer their own and other peoples’ visual perspectives, healthy adults experience difficulty ignoring the irrelevant perspective when the two perspectives are in conflict; they experience egocentric and altercentric interference. We examine for the first time how the age of an observed person (adult vs. child avatar) influences adults’ visual perspective-taking, particularly the degree to which they experience interference from their own or the other person’s perspective. Participants completed the avatar visual perspective-taking task, in which they verified the number of discs in a visual scene according to either their own or an on-screen avatar’s perspective (Experiments 1 and 2) or only from their own perspective (Experiment 3), where the two perspectives could be consistent or in conflict. Age of avatar was manipulated between (Experiment 1) or within (Experiments 2 and 3) participants, and interference was assessed using behavioral (Experiments 1–3) and ERP (Experiment 1) measures. Results revealed that altercentric interference is reduced or eliminated when a child avatar was present, suggesting that adults do not automatically compute a child avatar’s perspective. We attribute this pattern to either enhanced visual processing for own-age others or an inference on reduced mental awareness in younger children. The findings argue against a purely attentional basis for the altercentric effect, and instead support an account where both mentalising and directional processes modulate automatic visual perspective-taking, and perspective-taking effects are strongly influenced by experimental context.

An ERP study on metacognitive monitoring processes in children

Little is known about what exactly differentiates metacognitive processes from ordinary cognitive processes particularly early in development, and the underlying developmental aspects. To examine the time-course of metacognition, the present study investigated the neural underpinnings of judgments of learning (JoLs) and compared them with control judgments, using an event-related potentials (ERP) design. During ERP recording, children age seven to eight were presented with cue-target picture pairs and instructed to learn these pairs. After each pair, they either had to make a JoL (assess the likelihood of remembering the target when only presented with the cue) or a colour judgment (indicate whether the colour yellow had been present in one of the two pictures presented earlier). Results revealed a late slow wave divergence maximal pronounced from 550 ms to 950 ms post-stimulus that distinguished between JOLs and colour judgments. Over centro-parietal areas, JoLs showed a more negative going slow wave compared to the colour judgments, and this pattern was independent of performance. The results are in support of theories that assume a distinction between metacognitive and cognitive processes.

Neural correlates of children's emotion understanding

This study aimed to develop an EEG paradigm to identify neural correlates of emotion understanding in children. In Experiment 1, children took part in an emotional story task. In Experiment 2, children completed an emotional task and a physical story task Late Positive Potentials (LPP) were demonstrated in response to emotional content in both studies. Together, The study demonstrates the potential value of the LPP as a flexible probe for studying children's emotion understanding and encourages further work into the specificity versus generality of cognitive processes underpinning the LPP in social information processing.

Mental Rotation in False Belief Understanding

This study examines the spontaneous use of embodied egocentric transformation (EET) in understanding false beliefs in the minds of others. EET involves the participants mentally transforming or rotating themselves into the orientation of an agent when trying to adopt his or her visuospatial perspective. We argue that psychological perspective taking such as false belief reasoning may also involve EET because of what has been widely reported in the embodied cognition literature, showing that our processing of abstract, propositional information is often grounded in concrete bodily sensations which are not apparently linked to higher cognition. In Experiment 1, an agent placed a ball into one of two boxes and left. The ball then rolled out and moved either into the other box (new box) or back into the original one (old box). The participants were to decide from which box they themselves or the agent would try to recover the ball. Results showed that false belief performance was affected by increased orientation disparity between the participants and the agent, suggesting involvement of embodied transformation. In Experiment 2, false belief was similarly induced and the participants were to decide if the agent would try to recover the ball in one specific box. Orientation disparity was again found to affect false belief performance. The present results extend previous findings on EET in visuospatial perspective taking and suggest that false belief reasoning, which is a kind of psychological perspective taking, can also involve embodied rotation, consistent with the embodied cognition view.

Neural correlates of judgments of learning - An ERP study on metacognition

Metacognitive assessment of performance has been revealed to be one of the most powerful predictors of human learning success and academic achievement. Yet, little is known about the functional nature of cognitive processes supporting judgments of learning (JOLs). The present study investigated the neural underpinnings of JOLs, using event-related brain potentials. Participants were presented with picture pairs and instructed to learn these pairs. After each pair, participants received a task cue, which instructed them to make a JOL (the likelihood of remembering the target when only presented with the cue) or to make a control judgment. Results revealed that JOLs were accompanied by a positive slow wave over medial frontal areas and a bilateral negative slow wave over occipital areas between 350ms and 700ms following the task cue. The results are discussed with respect to recent accounts on the neural correlates of judgments of learning.

The Neural Correlates Underlying Belief Reasoning for Self and for Others: Evidence from ERPs

Belief reasoning is typical mental state reasoning in theory of mind (ToM). Although previous studies have explored the neural bases of belief reasoning, the neural correlates of belief reasoning for self and for others are rarely addressed. The decoupling mechanism of distinguishing the mental state of others from one’s own is essential for ToM processing. To address the electrophysiological bases underlying the decoupling mechanism, the present event-related potential study compared the time course of neural activities associated with belief reasoning for self and for others when the belief belonging to self was consistent or inconsistent with others. Results showed that during a 450–600 ms period, belief reasoning for self elicited a larger late positive component (LPC) than for others when beliefs were inconsistent with each other. The LPC divergence is assumed to reflect the categorization of agencies in ToM processes.

Conversation electrified: ERP correlates of speech act recognition in underspecified utterances

The ability to recognize speech acts (verbal actions) in conversation is critical for everyday interaction. However, utterances are often underspecified for the speech act they perform, requiring listeners to rely on the context to recognize the action. The goal of this study was to investigate the time-course of auditory speech act recognition in action-underspecified utterances and explore how sequential context (the prior action) impacts this process. We hypothesized that speech acts are recognized early in the utterance to allow for quick transitions between turns in conversation. Event-related potentials (ERPs) were recorded while participants listened to spoken dialogues and performed an action categorization task. The dialogues contained target utterances that each of which could deliver three distinct speech acts depending on the prior turn. The targets were identical across conditions, but differed in the type of speech act performed and how it fit into the larger action sequence. The ERP results show an early effect of action type, reflected by frontal positivities as early as 200 ms after target utterance onset. This indicates that speech act recognition begins early in the turn when the utterance has only been partially processed. Providing further support for early speech act recognition, actions in highly constraining contexts did not elicit an ERP effect to the utterance-final word. We take this to show that listeners can recognize the action before the final word through predictions at the speech act level. However, additional processing based on the complete utterance is required in more complex actions, as reflected by a posterior negativity at the final word when the speech act is in a less constraining context and a new action sequence is initiated. These findings demonstrate that sentence comprehension in conversational contexts crucially involves recognition of verbal action which begins as soon as it can.

Characterizing an ERP correlate of intentions understanding using a sequential comic strips paradigm

Chronometric properties of theory of mind and intentions understanding more specifically are well documented. Notably, it was demonstrated using magnetoencephalography that the brain regions involved were recruited as soon as 200 ms post-stimulus. We used event-related potentials (ERPs) to characterize an electrophysiological marker of attribution of intentions. We also explored the robustness of this ERP signature under two conditions corresponding to either explicit instructions to focus on others' intentions or implicit instructions with no reference to mental states. Two matched groups of 16 healthy volunteers each received either explicit or no instructions about intentions and performed a nonverbal attribution of intentions task based on sequential four-image comic strips depicting either intentional or physical causality. A bilateral posterior positive component, ranging from 250 to 650 ms post-stimulus, showed greater amplitude in intentional than in physical condition (the intention ERP effect). This effect occurs during the third image only, suggesting that it reflects the integration of information depicted in the third image to the contextual cues given by the first two. The intention effect was similar in the two groups of subjects. Overall, our results identify a clear ERP marker of the first hundreds of milliseconds of intentions processing probably related to a contextual integrative mechanism and suggest its robustness by showing its blindness to task demands manipulation.

Empathy predicts false belief reasoning ability: evidence from the N400

Interpreting others' actions relies on an understanding of their current mental state. Emerging research has begun to identify a number of factors that give rise to individual differences in this ability. We report an event-related brain potential study where participants (N = 28) read contexts that described a character having a true belief (TB) or false belief (FB) about an object's location. A second sentence described where that character would look for the object. Critically, this sentence included a sentence-final noun that was either consistent or inconsistent with the character's belief. Participants also completed the Empathy Quotient questionnaire. Analysis of the N400 revealed that when the character held a TB about the object's location, the N400 waveform was more negative-going for belief inconsistent vs belief consistent critical words. However, when the character held an FB about the object's location the opposite pattern was found. Intriguingly, correlations between the N400 inconsistency effect and individuals' empathy scores showed a significant correlation for FB but not TB. This suggests that people who are high in empathy can successfully interpret events according to the character's FB, while low empathizers bias their interpretation of events to their own egocentric view.

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

For a long time, a controversy has been proposed that whether the process of theory of mind is a result of domain-specific or domain-general changes (Wellman in The handbook of childhood cognitive development. Blackwell Publication, New Jersey, 2011). This event-related potential study explored the neural time course of domain-general and domain-specific components in belief reasoning. Fourteen participants completed location transfer false belief (FB), true belief (TB), false sign (FS) and true sign (TS) tasks, in which two pictures told a story related to a dog that ran from a green into a red box. In the TB and FB tasks, a boy saw or did not see the transfer of the dog, respectively. In the FS and TS tasks, an arrow that pointed to the green box either altered its direction to the red box or did not alter following the transfer of the dog. Participants then inferred where the boy thought of, or the arrow indicated the location of the dog. FB and TB reasoning elicited lower N2 amplitudes than FS and TS reasoning, which is associated with domain-general components, the detection, and classification. The late slow wave (LSW) for FB was more positive at frontal, central, and parietal sites than FS because of the domain-specific component involved in FB reasoning. However, the LSW was less positive for TB than for FB but did not differ from the TS condition, which implies that mental representation might not be involved in TB reasoning.

What's behind a P600? Integration operations during irony processing

The combined knowledge of word meanings and grammatical rules does not allow a listener to grasp the intended meaning of a speaker’s utterance. Pragmatic inferences on the part of the listener are also required. The present work focuses on the processing of ironic utterances (imagine a slow day being described as “really productive”) because these clearly require the listener to go beyond the linguistic code. Such utterances are advantageous experimentally because they can serve as their own controls in the form of literal sentences (now imagine an active day being described as “really productive”) as we employ techniques from electrophysiology (EEG). Importantly, the results confirm previous ERP findings showing that irony processing elicits an enhancement of the P600 component (Regel et al., 2011). More original are the findings drawn from Time Frequency Analysis (TFA) and especially the increase of power in the gamma band in the 280–400 time-window, which points to an integration among different streams of information relatively early in the comprehension of an irony. This represents a departure from traditional accounts of language processing which generally view pragmatic inferences as late-arriving. We propose that these results indicate that unification operations between the linguistic code and contextual information play a critical role throughout the course of irony processing and earlier than previously thought.

Same or different? ERP correlates of pretense and false belief reasoning in children

Pretend play, emerging at about 18 months, and explicit false belief (FB) understanding, arising around 4 years, constitute two pivotal milestones in the development of a Theory of Mind since both involve the ability to separate real from non-real content. The developmental lag has evoked vivid discussion with respect to whether or not pretense (PT) involves a metarepresentational understanding similar to FB. However, in children PT and FB have not yet been contrasted on a neural level to reveal whether they are subserved by the same neurocognitive mechanism. Therefore, the present event-related potential (ERP) study compared PT to a FB and to a non-mental control condition in 6- to 8-year-old children. Results revealed distinct ERP components for PT and FB. PT elicited a parietal P2, which was assumed to reflect the detection of incongruence, and a negative frontal slow wave (290-600 ms), which was associated with the identification of the intention underlying the pretend behavior. In contrast, FB evoked the characteristic positive fronto-central late slow wave (290-920 ms) that is supposed to indicate metarepresentation. Further, the broad distribution of the anterior slow-wave patterns associated with PT and FB reasoning was assumed to reflect the ongoing structural development and neural specialization of the respective areas, indicating the developmental progress in conceptualizing the mental domain. Given the differences in latency, polarity, and topography, PT and FB seem to rely on distinct neural substrates in children. The early negative frontal slow wave indicates that for PT reasoning children may use simple mentalizing processes such as intention processing, whereas the late positive slow-wave shows that for FB children may engage in metarepresentational processing. Therefore, the present findings seem to substantiate theoretical accounts postulating simple mentalistic reasoning for PT in children.