Neural correlates of belief- and desire-reasoning

Animacy Processing in Autism: Event-Related Potentials Reflect Social Functioning Skills

Though previous studies with autistic individuals have provided behavioral evidence of animacy perception difficulties, the spatio-temporal dynamics of animacy processing in autism remain underexplored. This study investigated how animacy is neurally encoded in autistic adults, and whether potential deficits in animacy processing have cascading deleterious effects on their social functioning skills. We employed a picture naming paradigm that recorded accuracy and response latencies to animate and inanimate pictures in young autistic adults and age- and IQ-matched healthy individuals, while also employing high-density EEG analysis to map the spatio-temporal dynamics of animacy processing. Participants' social skills were also assessed through a social comprehension task. The autistic adults exhibited lower accuracy than controls on the animate pictures of the task and also exhibited altered brain responses, including larger and smaller N100 amplitudes than controls on inanimate and animate stimuli, respectively. At late stages of processing, there were shorter slow negative wave latencies for the autistic group as compared to controls for the animate trials only. The autistic individuals' altered brain responses negatively correlated with their social difficulties. The results suggest deficits in brain responses to animacy in the autistic group, which were related to the individuals' social functioning skills.

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.

Intention affects fairness processing: Evidence from behavior and representational similarity analysis of event-related potential signals

In an ultimatum game, the responder must decide between pursuing self-interest and insisting on fairness, and these choices are affected by the intentions of the proposer. However, the time course of this social decision-making process is unclear. Representational similarity analysis (RSA) is a useful technique for linking brain activity with rich behavioral data sets. In this study, electroencephalography (EEG) was used to measure the time course of neural responses to proposed allocation schemes with different intentions. Twenty-eight participants played an ultimatum game as responders. They had to choose between accepting and rejecting the fair or unfair money allocation schemes of proposers. The schemes were offered based on the proposer's selfish intention (monetary gain), altruistic intention (donation to charity), or ambiguous intention (unknown to the responder). We used a spatiotemporal RSA and inter-subject RSA (IS-RSA) to explore the connections between event-related potentials (ERPs) after offer presentation and intention presentation with four types of behavioral data (acceptance, response time, fairness ratings, and pleasantness ratings). The spatiotemporal RSA results revealed that only response time variation was linked with the difference in ERPs at 432-592 ms after offer presentation on the posterior parietal and prefrontal regions. Meanwhile, the IS-RSA results found a significant association between inter-individual differences in response time and differences in ERP activity at 596-812 ms after the presentation of ambiguous intention, particularly in the prefrontal region. This study expands the intention-based reciprocal model to the third-party context and demonstrates that brain activity can represent response time differences in social decision-making.

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.

Temporal dynamics of explicit and implicit moral evaluations

Explicit moral evaluation is often accompanied with active attention and explicit responses to moral information, while implicit moral evaluation happens in passive attention and implicit response to moral information. Previous studies have pointed out the differences in the neural mechanisms underlying explicit and implicit moral processing on the spatial dimension, however, the temporal differences between these two processes have not been clear. This study aimed at comparing the temporal dynamics between explicit and implicit moral evaluation of harm/care-related moral scenarios with high/low emotional arousal by using event-related potentials (ERP) technique. The behavioral results showed that the accuracy of the explicit task is higher than that of the implicit task, especially for high-arousal moral actions. The ERP results mainly revealed that regardless of the task type, the brain responses to moral evaluations can be divided into early emotional arousal processing indexed by the frontal N1, moral intuition indexed by the frontal N2, and middle/late stages of processing integration of emotional arousal and moral cognition which involve elaborative processing and cognitive control, reflected by the frontal P2, parietal P3, parietal LPP, and FSW. Moreover, explicit and implicit moral evaluations mainly differed in the late stage of moral processing indexed by the P3, LPP and FSW. Our findings provide robust evidence for the "hybrid" model supposed by Huebner, which suggested that both explicit and implicit moral evaluations involved a complex interaction between emotional processes and moral cognition, and the later ERP results strongly supported that explicit and implicit moral evaluations represented two relatively independent processes, fitting the multinomial model supposed by Cameron.

Influence of Exposure at Different Altitudes on the Executive Function of Plateau Soldiers-Evidence From ERPs and Neural Oscillations

This study investigates the changes in soldiers' brain executive function at different altitude environments and their relationship with blood oxygen saturation. Stratified sampling was conducted in different altitude 133 active-duty soldiers who were stationed in Weinan (347 m, n = 34), Nyingchi (2,950 m, n = 32), Lhasa (3,860 m, n = 33), and Nagqu (4,890 m, n = 34) for 2 years. The Go/NoGo paradigm with event-related potentials (ERPs) and event-related oscillations (EROs) was used to explore the time and neural oscillation courses of response inhibition. Behavioral results revealed that at the 4,890-m altitude area, the soldiers had the highest false alarm rate, the longest reaction time, and the slowest information transmission rate. The electrophysiological results revealed that NoGo-N2 and N2d decreased with increasing altitude, with significant changes at 3,860 m; the amplitudes of NoGo-P3 and P3d in plateau groups were significantly more negative than the plain and changed significantly at 2,950 m. The results of correlation analysis showed that NoGo-P3 was negatively correlated with altitude (r = −0.358, p = 0.000), positively correlated with SpO₂ (r = 0.197, p = 0.041) and information translation rate (ITR) (r = 0.202, p = 0.036). P3d was negatively correlated with altitude (r = −0.276, p = 0.004) and positively correlated with ITR (r = 0.228, p = 0.018). N2d was negatively correlated with ITR (r = 0.204, p = 0.034). The power spectrum analysis of NoGo-N2 and NoGo-P3 showed that the power of δ and θ bands at the plateau area was significantly lower than the plain area and showed a significant step-by-step decrease; the α-band power increases significantly only in the area of 4,890 m. The effect of chronic hypoxia exposure at different altitudes of the plateau on the response inhibition of soldiers was manifested: 3,860 m was the altitude at which the brain response inhibition function decreased during the conflict monitoring stage, and 2,950 m was the altitude at which it dropped during the response inhibition stage. In addition, the soldier's brain's executive function was closely related to SpO₂, and a reduction in SpO₂ may lead to a decline in response inhibition.

Modeling Within-Item Dependencies in Parallel Data on Test Responses and Brain Activation

In this paper, we propose a joint modeling approach to analyze dependency in parallel response data. We define two types of dependency: higher-level dependency and within-item conditional dependency. While higher-level dependency can be estimated with common latent variable modeling approaches, within-item conditional dependency is a unique kind of information that is often not captured with extant methods, despite its potential to shed new insights into the relationship between the two types of response data. We differentiate three ways of modeling within-item conditional dependency by conditioning on raw values, expected values, or residual values of the response data, which have different implications in terms of response processes. The proposed approach is illustrated with the example of analyzing parallel data on response accuracy and brain activations from a Theory of Mind assessment. The consequence of ignoring within-item conditional dependency is investigated with empirical and simulation studies in comparison to conventional dependency analysis that focuses exclusively on relationships between latent variables.

Exploring neurophysiological markers of visual perspective taking: Methodological considerations

RATIONALE

For visual perspective taking (VPT) using the avatar task, examinations of neural processes using event related potentials (ERP) indicate a distinction between an early posterior perspective calculation process (P3) and a later frontal process (LFSW) managing perspective conflict. While it is unknown if these neural processes are affected in clinical populations, it is unclear if the avatar task can be applied to this group, due to the long duration and sensitivity to data loss. Thus, we performed a methodological study of the avatar task, testing the feasibility of a shortened experimental paradigm.

OBJECTIVE

To investigate whether previously reported behavioural and ERP effects in the avatar task can also be seen if analysing all trials (matching/non-matching) jointly, and whether they remain robust if only a subset of the data is analysed.

METHOD

Healthy individuals (n = 20) completed the avatar task with ERP measurement. ERP components (P3, LFSW) and behavioural data were investigated by A) comparing use of only matching trials (n = 384) versus all trials (n = 768), and B) examining if reduced duration of assessment, by analysing only a subset of the data, impacts ERP findings.

RESULTS

We observed minimal differences when analysing data from only matching trial types compared to all trial types. Further, ERP amplitudes and latency findings were replicated when analysing only a subset of the data.

CONCLUSIONS

The duration of the avatar task can be reduced to avoid long testing times, thus making it better suited for use in clinical populations.

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.

The neural and cognitive mechanisms of knowledge attribution: An EEG study

Despite the ubiquity of knowledge attribution in human social cognition, its associated neural and cognitive mechanisms are poorly documented. A wealth of converging evidence in cognitive neuroscience has identified independent perspective-taking and inhibitory processes for belief attribution, but the extent to which these processes are shared by knowledge attribution isn't presently understood. Here, we present the findings of an EEG study designed to directly address this shortcoming. These findings suggest that belief attribution is not a component process in knowledge attribution, contra a standard attitude taken by philosophers. Instead, observed differences in P3b amplitude indicate that knowledge attribution doesn't recruit the strong self-perspective inhibition characteristic of belief attribution. However, both belief and knowledge attribution were observed to display a late slow wave widely associated with mental state attribution, indicating that knowledge attribution also shares in more general processing of others' mental states. These results provide a new perspective both on how we think about knowledge attribution, as well as Theory of Mind processes generally.

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.

Trivariate Theory of Mind Data Analysis with a Conditional Joint Modeling Approach

Theory of mind (ToM) is an essential social-cognitive ability to understand one's own and other people's mental states. Neural data as well as behavior data have been utilized in ToM research, but the two types of data have rarely been analyzed together, creating a large gap in the literature. In this paper, we propose and apply a novel joint modeling approach to analyze brain activations with two types of behavioral data, response times and response accuracy, obtained from a multi-item ToM assessment, with the intention to shed new light on the nature of the underlying process of ToM reasoning. Our trivariate data analysis suggested that different levels or kinds of processes might be involved during the ToM assessment, which seem to differ in terms of cognitive efficiency and sensitivity to ToM items and the correctness of item responses. Additional details on the trivariate data analysis results are provided with discussions on their implications for ToM research.

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.

Continuity in the neural system supporting children's theory of mind development: Longitudinal links between task-independent EEG and task-dependent fMRI

Children's explicit theory of mind (ToM) understandings change over early childhood. We examined whether there is longitudinal stability in the neurobiological bases of ToM across this time period. A previous study found that source-localized resting EEG alpha attributable to the dorsal medial prefrontal cortex (DMPFC) and right temporoparietal junction (RTPJ) was associated with children's performance on a battery of theory of mind tasks. Here, we investigated a small subset of children (N = 12) in that original study as a preliminary investigation of whether behavioral measures of ToM performance, and/or EEG localized to the DMPFC or RTPJ predicted ToM-specific fMRI responses 3.5 years later. Results showed that preschoolers' behavioral ToM-performance positively predicted later ToM-specific fMRI responses in the DMPFC. Preschoolers' resting EEG attributable to the DMPFC also predicted later ToM-specific fMRI responses in the DMPFC. Given the small sample, results represent a first exploration and require replication. Intriguingly, they suggest that early maturation of the area of the DMPFC related to ToM reasoning is positively linked with its specific recruitment for ToM reasoning later in development, affording implications for characterizing conceptual ToM development, and its underlying neural supports.

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.

Age-related decline in emotional perspective-taking: Its effect on the late positive potential

Aging is associated with changes in cognitive and affective functioning, which likely shape older adults' social cognition. As the neural and psychological mechanisms underlying age differences in social abilities remain poorly understood, the present study aims to extend the research in this field. To this purpose, younger (n = 30; M_age = 26.6), middle-aged (n = 30; M_age = 48.4), and older adults (n = 29; M_age = 64.5) performed a task designed to assess affective perspective-taking, during an EEG recording. In this task, participants decided whether a target facial expression of emotion (FEE) was congruent or incongruent with that of a masked intervener of a previous scenario, which portrayed a neutral or an emotional scene. Older adults showed worse performance in comparison to the other groups. Regarding electrophysiological results, while younger and middle-aged adults showed higher late positive potentials (LPPs) after FEEs congruent with previous scenarios than after incongruent FEEs, older adults had similar amplitudes after both. This insensitivity of older adults' LPPs in differentiating congruent from incongruent emotional context-target FEE may be related to their difficulty in generating information about others' inner states and using that information in social interactions.

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.

Oscillatory brain activity differentially reflects false belief understanding and complementation syntax processing

False belief understanding (FBU) enables people to consider conflicting beliefs about the same situation. While language has been demonstrated to be a correlate of FBU, there is still controversy about the extent to which a specific aspect of language, complementation syntax, is a necessary condition for FBU. The present study tested an important notion from the debate proposing that complementation syntax task is redundant to FBU measures. Specifically, we examined electrophysiological correlates of false belief, false complementation, and their respective true conditions in adults using electroencephalography (EEG), focusing on indices of oscillatory brain activity and large-scale connectivity. The results showed strong modulation of parieto-occipital alpha (8-12 Hz) and beta (13-20 Hz) power by the experimental manipulations, with heightened sustained alpha power reflective of effortful internal processing observed in the false compared to the true conditions and reliable beta power reductions sensitive to mentalizing and/or syntactic demands in the belief versus the complementation conditions. In addition, higher coupling between parieto-occipital regions and widespread frontal sites in the beta band was found for the false-belief condition selectively. The result of divergence in beta oscillatory activity and in connectivity between false belief and false complementation does not support the redundancy hypothesis.

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.

Thinking about the thoughts of others; temporal and spatial neural activation during false belief reasoning

Theory of Mind (ToM) is the ability to understand the perspectives, mental states and beliefs of others in order to anticipate their behaviour and is therefore crucial to social interactions. Although fMRI has been widely used to establish the neural networks implicated in ToM, little is known about the timing of ToM-related brain activity. We used magnetoencephalography (MEG) to measure the neural processes underlying ToM, as MEG provides very accurate timing and excellent spatial localization of brain processes. We recorded MEG activity during a false belief task, a reliable measure of ToM, in twenty young adults (10 females). MEG data were recorded in a 151 sensor CTF system (MISL, Coquitlam, BC) and data were co-registered to each participant's MRI (Siemens 3T) for source reconstruction. We found stronger right temporoparietal junction (rTPJ) activations in the false belief condition from 150ms to 225ms, in the right precuneus from 275ms to 375ms, in the right inferior frontal gyrus from 200ms to 300ms and the superior frontal gyrus from 300ms to 400ms. Our findings extend the literature by demonstrating the timing and duration of neural activity in the main regions involved in the "mentalizing" network, showing that activations related to false belief in adults are predominantly right lateralized and onset around 100ms. The sensitivity of MEG will allow us to determine spatial and temporal differences in the brain processes in ToM in younger populations or those who demonstrate deficits in this ability.

The neural basis of desire reasoning for self and others: an event-related potential study

Theory of mind refers to the ability to attribute mental states to self and others, and predict actions in terms of mental states. It is still unclear how certain kinds of processing occur in theory of mind operation. The present study compared neural activities elicited by desire reasoning for self and for others under consistent or inconsistent conditions using the event-related potential method. The results showed that the late positive component (LPC) associated with desire reasoning was larger during the 450-550 ms time period in the condition of reasoning for self than that for others when desires were inconsistent. A left hemisphere effect on the scalp distribution was observed for the LPC component. The present study showed that a left frontal LPC component might reflect the subjective categorization process in desire reasoning.

Temporal Dynamics of the Integration of Intention and Outcome in Harmful and Helpful Moral Judgment

The ability to integrate the moral intention information with the outcome of an action plays a crucial role in mature moral judgment. Functional magnetic resonance imaging (fMRI) studies implicated that both prefrontal and temporo-parietal cortices are involved in moral intention and outcome processing. Here, we used the event-related potentials (ERPs) technique to investigate the temporal dynamics of the processing of the integration between intention and outcome information in harmful and helpful moral judgment. In two experiments, participants were asked to make moral judgments for agents who produced either negative/neutral outcomes with harmful/neutral intentions (harmful judgment) or positive/neutral outcomes with helpful/neutral intentions (helpful judgment). Significant ERP differences between attempted and successful actions over prefrontal and bilateral temporo-parietal regions were found in both harmful and helpful moral judgment, which suggest a possible time course of the integration processing in the brain, starting from the right temporo-parietal area (N180) to the left temporo-parietal area (N250), then the prefrontal area (FSW) and the right temporo-parietal area (TP450 and TPSW) again. These results highlighted the fast moral intuition reaction and the late integration processing over the right temporo-parietal area.

On the Role of Mentalizing Processes in Aesthetic Appreciation: An ERP Study

We used event-related brain potentials to explore the impact of mental perspective taking on processes of aesthetic appreciation of visual art. Participants (non-experts) were first presented with information about the life and attitudes of a fictitious artist. Subsequently, they were cued trial-wise to make an aesthetic judgment regarding an image depicting a piece of abstract art either from their own perspective or from the imagined perspective of the fictitious artist [i.e., theory of mind (ToM) condition]. Positive self-referential judgments were made more quickly and negative self-referential judgments were made more slowly than the corresponding judgments from the imagined perspective. Event-related potential analyses revealed significant differences between the two tasks both within the preparation period (i.e., during the cue-stimulus interval) and within the stimulus presentation period. For the ToM condition we observed a relative centro-parietal negativity during the preparation period (700-330 ms preceding picture onset) and a relative centro-parietal positivity during the stimulus presentation period (700-1100 ms after stimulus onset). These findings suggest that different subprocesses are involved in aesthetic appreciation and judgment of visual abstract art from one's own vs. from another person's perspective.

Children's belief- and desire-reasoning in the temporoparietal junction: evidence for specialization from functional near-infrared spectroscopy

Behaviorally, children's explicit theory of mind (ToM) proceeds in a progression of mental-state understandings: developmentally, children demonstrate accurate explicit desire-reasoning before accurate explicit belief-reasoning. Given its robust and cross-cultural nature, we hypothesize this progression may be paced in part by maturation/specialization of the brain. Neuroimaging research demonstrates that the right temporoparietal junction (TPJ) becomes increasingly selective for ToM reasoning as children age, and as their ToM improves. But this research has narrowly focused on beliefs or on undifferentiated mental-states. A recent ERP study in children included a critical contrast to desire-reasoning, and demonstrated that right posterior potentials differentiated belief-reasoning from desire-reasoning. Taken together, the literature suggests that children's desire-belief progression may be paced by specialization of the right TPJ for belief-reasoning specifically, beyond desire-reasoning. In the present study, we tested this hypothesis directly by examining children's belief- and desire-reasoning using functional near-infrared spectroscopy in conjunction with structural magnetic resonance imaging to pinpoint brain activation in the right TPJ. Results showed greatest activation in the right TPJ for belief-reasoning, beyond desire-reasoning, and beyond non-mental reasoning (control). Findings replicate and critically extend prior ERP results, and provide clear evidence for a specific neural mechanism underlying children's progression from understanding desires to understanding beliefs.

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.

Spatio-temporal dynamics of kind versus hostile intentions in the human brain: An electrical neuroimaging study

Neuroscience research suggests that inferring neutral intentions of other people recruits a specific brain network within the inferior fronto-parietal action observation network as well as a putative social network including brain areas subserving theory of mind, such as the posterior superior temporal sulcus (pSTS), the temporo-parietal junction (TPJ), and also the anterior cingulate cortex (ACC). Recent studies on harmful intentions have refined this network by showing the specific involvement of the ACC, amygdala, and ventromedial prefrontal cortex (vmPFC) in early stages (within 200 ms) of information processing. However, the functional dynamics for kind intentions within and among these networks remains unclear. To address this question, we measured electrical brain activity from 18 healthy adult participants while they were performing an intention inference task with three different types of intentions: kind, hostile and non-interactive. Electrophysiological results revealed that kind intentions were characterized by significantly larger peak amplitudes of N2 over the frontal sites than those for hostile and non-interactive intentions. On the other hand, there were no significant differences between hostile and non-interactive intentions at N2. The source analysis suggested that the vicinity of the left cingulate gyrus contributed to the N2 effect by subtracting the kindness condition from the non-interactive condition within 250-350 ms. At a later stage (i.e., during the 270-500 ms epoch), the peak amplitude of the P3 over the parietal sites and the right hemisphere was significantly larger for hostile intentions compared to the kind and non-interactive intentions. No significant differences were observed at P3 between kind and non-interactive intentions. The source analysis showed that the vicinity of the left anterior cingulate cortex contributed to the P3 effect by subtracting the hostility condition from the non-interactive condition within 450-550 ms. The present study provides preliminary evidence of the spatio-temporal dynamics sustaining the dissociation between the understandings of different types of social intentions.

Spontaneous mentalizing captures variability in the cortical thickness of social brain regions

Theory of mind (ToM)--or thinking about the mental states of others--is a cornerstone of successful everyday social interaction. However, the brain bases of ToM are most frequently measured via explicit laboratory tasks that pose direct questions about mental states (e.g. "In this story, what does Steve think Julia believes?"). Neuroanatomical measures may provide a way to explore the brain bases of individual differences in more naturalistic everyday mentalizing. In the current study, we examined the relation between cortical thickness and spontaneous ToM using the novel Spontaneous Theory of Mind Protocol (STOMP), which measures participants' spontaneous descriptions of the beliefs, emotions and goals of characters in naturalistic videos. We administered standard ToM tasks and the STOMP to young adults (aged 18-26 years) and collected structural magnetic resonance imaging data from a subset of these participants. The STOMP produced robust individual variability and was correlated with performance on traditional ToM tasks. Further, unlike the traditional ToM tasks, STOMP performance was related to cortical thickness for a set of brain regions that have been functionally linked to ToM processing. These findings offer novel insight into the brain bases of variability in naturalistic mentalizing performance, with implications for both typical and atypical populations.

How and where: theory-of-mind in the brain

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Neuroscience has the potential to address accounts of theory-of-mind acquisition.

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Review of the research on the neural basis of theory-of-mind in adults and children.

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Future research directions include microgenetic and training fMRI studies.

Theory of mind (ToM) is a core topic in both social neuroscience and developmental psychology, yet theory and data from each field have only minimally constrained thinking in the other. The two fields might be fruitfully integrated, however, if social neuroscientists sought evidence directly relevant to current accounts of ToM development: modularity, simulation, executive, and theory theory accounts. Here we extend the distinct predictions made by each theory to the neural level, describe neuroimaging evidence that in principle would be relevant to testing each account, and discuss such evidence where it exists. We propose that it would be mutually beneficial for both fields if ToM neuroimaging studies focused more on integrating developmental accounts of ToM acquisition with neuroimaging approaches, and suggest ways this might be achieved.

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.

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.

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

Two important milestones characterize the development of a theory of mind (ToM): The emergence of pretend play (PT) in which infants as young as 18 months separate the real world from fictional or imagined worlds. And the explicit understanding of false beliefs (FB) which develops around the age of about 4 years and demands a differentiation between mental states and reality. Although there is an outstanding debate about whether or not PT play involves metarepresentation understanding, to date, the neural correlates of FB and PT reasoning have not been investigated within one paradigm. The present study investigated PT and FB in comparison to reality understanding (RE) in an ERP paradigm presenting cartoon stories to 24 healthy adults. Results revealed a sequence of ERP components that distinguished between the conditions. PT compared to FB and RE was associated with a higher P2-amplitude at parieto-occipital sites and a late slow wave divergence (270-600 ms) at left frontal and left posterior positions. These components may indicate the processing of incongruity between the protagonist's knowledge and behavior and the identifying of the intentional character of the pretended action. In accordance with previous ERP studies on FB reasoning, we found late anterior activation (600-900 ms) for FB reasoning, probably indicating the decoupling mechanism involved in metarepresentation. These temporal and topographic differences indicate distinct underlying neural substrates for FB and PT processing, and do not support metarepresentational interpretations of PT.

Neural correlates of belief- and desire-reasoning in 7- and 8-year-old children: an event-related potential study

Theory of mind requires belief- and desire-understanding. Event-related brain potential (ERP) research on belief- and desire-reasoning in adults found mid-frontal activations for both desires and beliefs, and selective right-posterior activations only for beliefs. Developmentally, children understand desires before beliefs; thus, a critical question concerns whether neural specialization for belief-reasoning exists in childhood or develops later. Neural activity was recorded as 7- and 8-year-olds (N = 18) performed the same diverse-desires, diverse-beliefs, and physical control tasks used in a previous adult ERP study. Like adults, mid-frontal scalp activations were found for belief- and desire-reasoning. Moreover, analyses using correct trials alone yielded selective right-posterior activations for belief-reasoning. Results suggest developmental links between increasingly accurate understanding of complex mental states and neural specialization supporting this understanding.

The neural correlates of passively viewed sequences of true and false beliefs

The ability to infer other people's mental states such as desires, emotions, intentions and beliefs is essential for successful social interactions, and it is usually referred to as theory of mind (ToM). In particular, the ability to detect and understand that people have beliefs about reality that may be false is considered an important hallmark of ToM. This experiment reports on the results of 18 participants who viewed photographic sequences of an actress performing actions as a consequence of true and false beliefs. Consistent with prior work, results from the passive viewing of stimuli depicting true belief indicated an increased response over frontal, central and parietal regions when compared with the amplitude for the false belief condition. These results show that (i) frontal activity is required for processing false belief tasks and (ii) parietal effects reported in previous studies to reflect specific cognitive process of monitoring others' beliefs can be elicited in the absence of an explicit instruction for mentalizing.

The neural and cognitive time course of theory of mind

Neuroimaging and neuropsychological studies implicate both frontal and temporoparietal cortices when humans reason about the mental states of others. Here, we report an event-related potentials study of the time course of one such "theory of mind" ability: visual perspective taking. The findings suggest that posterior cortex, perhaps the temporoparietal cortex, calculates and represents the perspective of self versus other, and then, later, the right frontal cortex resolves conflict between perspectives during response selection.

Electrophysiological correlates of reading the single- and interactive-mind

Understanding minds is the cognitive basis of successful social interaction. In everyday life, human mental activity often happens at the moment of social interaction among two or multiple persons instead of only one-person. Understanding the interactive mind of two- or multi-person is more complex and higher than understanding the single-person mind in the hierarchical structure of theory of mind. Understanding the interactive mind maybe differentiate from understanding the single mind. In order to examine the dissociative electrophysiological correlates of reading the single mind and reading the interactive mind, the 64 channels event-related potentials were recorded while 16 normal adults were observing three kinds of Chinese idioms depicted physical scenes, one-person with mental activity, and two- or multi-person with mental interaction. After the equivalent N400, in the 500- to 700-ms epoch, the mean amplitudes of late positive component (LPC) over frontal for reading the single mind and reading the interactive mind were significantly more positive than for physical representation, while there was no difference between the former two. In the 700- to 800-ms epoch, the mean amplitudes of LPC over frontal-central for reading the interactive mind were more positive than for reading the single mind and physical representation, while there was no difference between the latter two. The present study provides electrophysiological signature of the dissociations between reading the single mind and reading the interactive mind.

True- and false-belief reasoning in children and adults: an event-related potential study of theory of mind

The understanding that another person's belief can differ from reality and that behaviour is guided by beliefs and not by reality reflects an important cornerstone in the development of a Theory of Mind. The present event-related potential (ERP) study had two aims: first, to reveal ERPs that distinguish between false- and true-belief reasoning and second, to investigate the neural changes in the development of false- and true-belief reasoning from childhood to adulthood. True- and false-belief cartoon stories were presented to adults and 6-8-year-old children. Results revealed two waveforms that differentiated between the two conditions: a late positive complex (LPC) associated with the reorientation from external stimuli to internal mental representations and a late anterior slow wave (LSW) associated with stimulus-independent processing of internal mental representations, a process that might be centrally involved in the decoupling mechanism. Additionally, we found developmental effects at an ERP level. Children showed a more posterior localization of the LPC and a broader frontal distribution of the LSW. The results may reflect developmental progress in conceptualizing the mental domain and support the idea that the cortical mentalizing network continues to develop even after children are able to master false beliefs.