Measuring Mentalizing Ability: A Within-Subject Comparison between an Explicit and Implicit Version of a Ball Detection Task

Theta-Burst Stimulation of the Right Temporoparietal Junction and Implicit Theory of Mind in Autism

OBJECTIVES

Theory of mind (ToM), or mentalizing, is the ability to attribute mental states to oneself and others and is altered in individuals with autism spectrum disorder (ASD). Recent evidence suggests that implicit rather than explicit ToM is impaired in individuals with ASD. The right temporoparietal junction (rTPJ), which plays a crucial role in ToM, has altered activity in ASD and is a potential terget by noninvasive brain stimulation.

MATERIALS AND METHODS

In a randomized single-blind placebo-controlled study, we investigated, for what we believe is the first time, the effects of theta-burst stimulation of the rTPJ on implicit ToM and egocentric bias in 17 adolescents with ASD. Participants (mean age = 13.84 ± 3.32 years) were randomly assigned to three sessions of continuous theta-burst stimulation (cTBS), intermittent theta-burst stimulation (iTBS), and sham stimulation in a counterbalanced order. Stimulation intensity was set to 80% of the active motor threshold during cTBS and iTBS, with the coil centered on the rTPJ (CP6). Immediately after each stimulation, cognitive correlates of ToM, including implicit mentalizing and egocentric bias, were evaluated using the computerized Buzz-lightyear task.

RESULTS

Both cTBS and iTBS significantly improved implicit ToM compared with sham stimulation, with cTBS yielding a numerically larger effect (379.2 milliseconds) than did iTBS (191.3 milliseconds), although this difference was not statistically significant. No effect was found on the egocentric bias index.

CONCLUSIONS

These findings show a causal link between the rTPJ activation and implicit mentalizing in ASD, suggesting that theta-burst stimulation of this region can be used to enhance ToM in ASD. Targeting the rTPJ may improve implicit mentalizing in ASD and other disorders with impaired ToM.

Fragile Mentalizing: Lack of Behavioral and Neural Markers of Social Cognition in an Established Social Perspective Taking Task when Combined with Stress Induction

The growing field of social neuroscience is reliant on the development of robust, ecologically valid paradigms for simulating social interaction and measuring social cognition in highly controlled laboratory settings. Perspective taking is a key component of social cognition, and accordingly several paradigms aimed at measuring perspective taking exist. A relatively novel paradigm is the ball detection task, in which participants and a virtual agent form independent beliefs about the presence of a target stimulus behind an occluder. Previous studies have shown that incongruent trials (in which the participant's and the agent's beliefs differ) affect participant reaction times and elicit increased neural activity in the so-called mentalizing network. This paradigm has important advantages over previous ones, in that experimental conditions can be fully randomized, and ceiling effects are not found even for adult populations. Here, we combined this paradigm with a stress induction and a nonstressful control task. In an online study, we found no evidence of perspective taking at the behavioral level. Combining the task with functional magnetic resonance imaging, we found no evidence of perspective taking at the behavioral or neural level, even for the control condition. While this paradigm is reliable on its own, implementing it in the context of a task-switching paradigm appears to reduce participants' focus on task-irrelevant perspective taking elements. Our findings highlight the fragility of existing social cognition paradigms and the need for reliable, simple, and ecologically valid measures of perspective taking.

Perceptual discrimination of action formidableness and friendliness and the impact of autistic traits

The ability to determine whether the actions of other individuals are friendly or formidable are key decisions we need to make to successfully navigate our complex social environment. In this study we measured perceptual performance when discriminating actions that vary in their friendliness or formidableness, and whether performance was related to the autistic traits of individuals. To do this, we developed an action morphing method to generate novel actions that lied along the action quality dimensions of formidableness and friendliness. In Experiment 1 we show that actions that vary along the formidableness or friendliness continua were rated as varying monotonically along the respective quality. In Experiment 2 we measured the ability of individuals with different levels of autistic traits to discriminate action formidableness and friendliness using adaptive 2-AFC procedures. We found considerable variation in perceptual thresholds when discriminating action formidableness (~ 540% interindividual variation) or friendliness (~ 1100% interindividual variation). Importantly, we found no evidence that autistic traits influenced perceptual discrimination of these action qualities. These results confirm that sensory enhancements with autistic traits are limited to lower level stimuli, and suggest that the perceptual processing of these complex social signals are not affected by autistic traits.

Flexible social monitoring as revealed by eye movements: Spontaneous mental state updating triggered by others' unexpected actions

Successful interactions require not only representing others' mental states but also flexibly updating them, whenever one's original inferences may no longer hold. Such situations arise, for instance, when a partner's behavior is incongruent with one's expectations. Although these situations are rather common, the question whether people update others' mental states spontaneously upon encountering unexpected behaviors and whether they use the updated mental states in novel contexts, has been largely unexplored. We addressed these issues in two experiments. In each experiment participants first performed an anticipatory looking task, reacting to a virtual 'partner', who categorized pictures based on their ambiguous or non-ambiguous color. Importantly, to perform the task participants did not have to track their partner's perspective. Following a correct categorization phase, the 'partner' started to systematically miscategorize one of the ambiguous colors (e.g., as if she would now believe that the greenish blue is green). We measured how participants' anticipatory looking preceding the partner's categorization changed across trials. Afterward, we asked whether participants implicitly transferred their knowledge about the partner's updated perspective to a new task. Finally, they performed an explicit perspective-taking task, to test whether they selectively updated the partner's perspective, but not their own. Results revealed that correct anticipations started to emerge only after a few miscategorizations, indicating the spontaneous updating of the other's perspective regarding the miscategorized color. Signatures of updating emerged somewhat earlier when the partner made similarity judgments (Experiment 2), highlighting the subjective nature of her decisions, compared to when following an explicit color-categorization rule (Experiment 1). In the explicit perspective-taking task of both experiments, roughly half of the participants could categorize items according to the partner's (spontaneously updated) perspective and also used their partner's updated perspective in the implicit transfer task to some degree, while they were the ones who displayed more pronounced anticipatory patterns as well. Such data provides strong evidence that the observed changes in anticipatory looking reflect spontaneous and flexible mental state updating. In addition, the findings also point to a high individual variability both in the updating of attributed mental states and the use of the updated mental state content.

Evaluative contexts facilitate implicit mentalizing: relation to the broader autism phenotype and mental health

One promising account for autism is implicit mentalizing difficulties. However, this account and even the existence of implicit mentalizing have been challenged because the replication results are mixed. Those unsuccessful replications may be due to the task contexts not being sufficiently evaluative. Therefore, the current study developed a more evaluative paradigm by implementing a prompt question. This was assessed in 60 non-autistic adults and compared with a non-prompt version. Additionally, parents of autistic children are thought to show a genetic liability to autistic traits and cognition and often report mental health problems, but the broader autism phenotype (BAP) is an under-researched area. Thus, we also aimed to compare 33 BAP and 26 non-BAP mothers on mentalizing abilities, autistic traits, compensation and mental health. Our results revealed that more evaluative contexts can facilitate implicit mentalizing in BAP and non-BAP populations, and thus improve task reliability and replicability. Surprisingly, BAP mothers showed better implicit mentalizing but worse mental health than non-BAP mothers, which indicates the heterogeneity in the broader autism phenotype and the need to promote BAP mothers' psychological resilience. The findings underscore the importance of contexts for implicit mentalizing and the need to profile mentalizing and mental health in BAP parents.

Principles of belief acquisition. How we read other minds

Reading other minds is a pervasive feature of human social life. A decade of research indicates that people can automatically track an agent's beliefs regardless of whether this is required. But little is known about the principles t guide automatic belief tracking. In six experiments adapting a false belief task introduced by Kovács et al. (2010), we tested whether belief tracking is interrupted by either an agent's lack of perceptual access or else by an agent's constrained action possibilities. We also tested whether such manipulations create interruptions when participants were instructed to track beliefs. Our main finding: the agent's lack of perceptual access did not interrupt belief tracking when participants were not instructed to track beliefs. Overall, our findings raise a challenge: some of the phenomena that have been labelled mindreading are perhaps not mindreading at all, or-more likely-they are mindreading but not as we know it.

Sex differences in autistic adults: A preliminary study showing differences in mentalizing, but not in narrative coherence

Studying autism might be a complex endeavor due to its clinical heterogeneity. Little is currently known about potential sex differences in autistic adults, especially regarding mentalizing and narrative coherence. In this study, male and female participants told a personal story about one of their most positive and most negative life events and performed two mentalizing tasks. One of these mentalizing tasks was a recently developed Picture and Verbal Sequencing task that has shown cerebellar recruitment, and which requires mentalizing in a sequential context (i.e., participants chronologically ordered scenarios that required true and false belief mentalizing). Our preliminary comparison shows that males were faster and more accurate on the Picture Sequencing task compared to female participants when ordering sequences involving false beliefs, but not true beliefs. No sex differences were found for the other mentalizing and narrative tasks. These results highlight the importance of looking at sex differences in autistic adults and provide a possible explanation for sex-related differences in daily life mentalizing functions, which suggest a need for more sensitive diagnosis and tailored support.

Mentalizing and narrative coherence in autistic adults: Cerebellar sequencing and prediction

BYLEMANS, T., et al. Mentalizing and narrative coherence in autistic adults: Cerebellar sequencing and prediction. NEUROSCI BIOBEHAV REV, 2022. - This review focuses on autistic adults and serves 4 purposes: (1) providing an overview of their difficulties regarding mentalizing (understanding others' mental states) and narrative coherence (structured storytelling), (2) highlighting the relations between both skills by examining behavioral observations and shared neural substrates, (3) providing an integrated perspective regarding novel diagnostic tools and support services, and (4) raising awareness of adult autism. We suggest that mentalizing and narrative coherence are related at the behavioral level and neural level. In addition to the traditional mentalizing network, the cerebellum probably serves as an important hub in shared cerebral networks implicated in mentalizing and narrative coherence. Future autism research and support services should tackle new questions within a framework of social cerebellar (dys)functioning.

The social roots of self development: from a bodily to an intellectual interpersonal dialogue

In this paper, we propose that interpersonal bodily interactions represent a fertile ground in which the bodily and psychological self is developed, gradually allowing for forms of more abstract and disembodied interactions. We start by focusing on how early infant-caregiver bodily interactions play a crucial role in shaping the boundaries of the self but also in learning to predict others' behavior. We then explore the social function of the sense of touch in the entire life span, highlighting its role in promoting physical and psychological well-being by supporting positive interpersonal exchanges. We go on by introducing the concept of implicit theory of mind, as the early ability to interpret others' intentions, possibly grounded in infant-caregiver bodily exchanges (embodied practices). In the following part, we consider so-called higher level forms of social interaction: intellectual exchanges among individuals. In this regard, we defend the view that, beside the apparent private dimension of "thinking abstractly", using abstract concepts is intrinsically a social process, as it entails the re-enactment of the internalized dialogue through which we acquired the concepts in the first place. Finally, we describe how the hypothesis of "dialectical attunement" may explain the development of abstract thinking: to effectively transform the world according to their survival needs, individuals co-construct structured concepts of it; by doing so, humans fundamentally transform not merely the world they are being in, but their being in the world.

The effects of developmental trauma on theory of mind and its relationship to psychotic experiences: A behavioural study

BACKGROUND

Developmental psychological trauma induces vulnerability to psychosis. However, the mechanisms underlying this association are poorly understood. Impairments in Theory of Mind (ToM) have been observed in adult survivors of developmental trauma and individuals with psychosis. ToM is therefore a candidate mechanism underlying the association between developmental trauma and psychosis.

METHODS

We used a computerised version of the Director task - where a participant is instructed by a confederate to move an object around a 4 × 4 grid, whilst taking account of whether these objects are visible to a confederate who instructs the participant - to investigate impairments in ToM in 209 participants (age: M = 37.8, SD=13.6; 56% female). Participants were divided into a) developmental trauma-positive (DT+) and control groups (DT-) based on their history of developmental trauma and b) then further into subclinical (S) and healthy groups (H) as based on psychotic experiences indexed by the CAPE-P15. After exclusion, the numbers in each group were: DT+H (47), DT+S (84), DT-H (54), DT-S (12). (Total: 197).

RESULTS

Developmental trauma exposure was associated with psychotic experiences (OR: 7.89, p < .001), which remained significant after controlling for demographic and clinical confounds (adjusted R² = 0.452, R² change = 0.0184, p = .009). Participants with developmental trauma (F_{1, 194}) = 5.46, p = .020, ηp² = 0.027) and participants more prone to psychotic experiences (F_{1, 194}) = 4.71, p = .031, ηp² = 0.024) demonstrated significantly lower accuracy on the Director task relative to their respective control, after controlling for the effects of age.

CONCLUSIONS

ToM deficits are associated with self-reported developmental trauma and psychotic experiences. Further work is needed to explore these relationships further and whether they represent generalised or specific effect effects on developmental trauma and psychopathological domains.

Implicit Mentalizing in Patients With Schizophrenia: A Systematic Review and Meta-Analysis

INTRODUCTION

Mentalizing is a key aspect of social cognition. Several researchers assume that mentalization has two systems, an explicit one (conscious, relatively slow, flexible, verbal, inferential) and an implicit one (unconscious, automatic, fast, non-verbal, intuitive). In schizophrenia, several studies have confirmed the deficit of explicit mentalizing, but little data are available on non-explicit mentalizing. However, increasing research activity can be detected recently in implicit mentalizing. The aim of this systematic review and meta-analysis is to summarize the existing results of implicit mentalizing in schizophrenia.

METHODS

A systematic search was performed in four major databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science. Eleven publications were selected. Five studies were found to be eligible for quantitative synthesis, and 9 studies were included in qualitative synthesis.

RESULTS

The meta-analysis revealed significantly lower accuracy, slower reaction time during implicit mentalizing in patients with schizophrenia. The systematic review found different brain activation pattern, further alterations in visual scanning, cue fixation, face looking time, and difficulties in perspective taking.

DISCUSSION

Overall, in addition to the deficit of explicit mentalization, implicit mentalization performance is also affected in schizophrenia, if not to the same extent. It seems likely that some elements of implicit mentalization might be relatively unaffected (e.g., detection of intentionality), but the effectiveness is limited by certain neurocognitive deficits. These alterations in implicit mentalizing can also have potential therapeutic consequences.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42021231312.

Spontaneous attribution of false beliefs in adults examined using a signal detection approach

Understanding other people have beliefs different from ours or different from reality is critical to social interaction. Previous studies suggest that healthy adults possess an implicit mentalising system, but alternative explanations for data from reaction time false belief tasks have also been given. In this study, we combined signal detection theory (SDT) with a false belief task. As application of SDT allows us to separate perceptual sensitivity from criteria, we are able to investigate how another person's beliefs change the participant's perception of near-threshold stimuli. Participants (n = 55) watched four different videos in which an actor saw (or did not see) a Gabor cube hidden (or not hidden) behind an occluder. At the end of each video, the occluder vanished revealing a cube either with or without Gabor pattern, and participants needed to report whether they saw the Gabor pattern or not. A pre-registered analysis with classical statistics weakly suggests an effect of the actor's belief on participant's perceptions. An exploratory Bayesian analysis supports the idea that when the actor believed the cube was present, participants made slower and more liberal judgements. Although these data are not definitive, these current results indicate the value of new measures for understanding implicit false belief processing.

Mindreading in the balance: adults' mediolateral leaning and anticipatory looking foretell others' action preparation in a false-belief interactive task

Anticipatory looking on mindreading tasks can indicate our expectation of an agent's action. The challenge is that social situations are often more complex, involving instances where we need to track an agent's false belief to successfully identify the outcome to which an action is directed. If motor processes can guide how action goals are understood, it is conceivable-where that kind of goal ascription occurs in false-belief tasks-for motor representations to account for someone's belief-like state. Testing adults (N = 42) in a real-time interactive helping scenario, we discovered that participants' early mediolateral motor activity (leftwards-rightwards leaning on balance board) foreshadowed the agent's belief-based action preparation. These results suggest fast belief-tracking can modulate motor representations generated in the course of one's interaction with an agent. While adults' leaning, and anticipatory looking, revealed the contribution of fast false-belief tracking, participants did not correct the agent's mistake in their final helping action. These discoveries suggest that adults may not necessarily use another's belief during overt social interaction or find reflecting on another's belief as being normatively relevant to one's own choice of action. Our interactive task design offers a promising way to investigate how motor and mindreading processes may be variously integrated.

Is social cognitive training efficient in autism? A pilot single-case study using the RC2S+ program

In high-functioning autism, deficits in emotional processing and theory of mind are relevant to understanding the particularities of social functioning. Here we used a multiple baseline and ABA single-case design to assess the efficacy of an individualized social cognitive training program using both pen-and-paper and computerized materials for an 18-year old patient. After the treatment phase, we found significant improvement in both emotional processes and theory of mind. These results provide further significant data showing that therapeutic tools based on digital relational simulation are a promising way for helping people with autism to compensate for their impaired social functioning.

Level 2 perspective-taking distinguishes automatic and non-automatic belief-tracking

Little is known about whether human beings' automatic mindreading is computationally restricted to processing a limited kind of content, and what exactly the nature of that signature limit might be. We developed a novel object-detection paradigm to test adults' automatic processing in a Level 1 perspective-taking (L1PT) context (where an agent's belief, but not his visuospatial perspective, is relevantly different) and in a Level 2 perspective-taking (L2PT) context (where both the agent's belief and visuospatial perspective are relevantly different). Experiment 1 uncovered that adults' reaction times in the L1PT task were helpfully speeded by a bystander's irrelevant belief when tracking two homogenous objects but not in the L2PT task when tracking a single heterogeneous object. The limitation is especially striking given that the heterogeneous nature of the single object was fully revealed to participants as well as the bystander. The results were replicated in two further experiments, which confirmed that the selective modulation of adults' reaction times was maintained when tracking the location of a single object (Experiment 2) and when attention checks were removed (Experiment 3). Our findings suggest that automatic mindreading draws upon a distinctively minimalist model of the mental that underspecifies representation of differences in perspective relative to an agent's position in space.

Recent Advances and New Directions in Measuring Theory of Mind in Autistic Adults

'Theory of Mind' (ToM) is the ability to attribute mental states to others to make sense of their behaviour. ToM research has informed understanding of (a)typical social behaviour, including the symptoms of autism spectrum disorder (ASD). This began with research on ToM in autistic children and there has been a noticeable increase in the study of ToM in autistic adults. However, methodological limitations in adult ToM research may be limiting its explanatory power of ASD symptoms and their management, therefore we discuss recent advances in measuring ToM aimed at addressing these issues. We also examine previously overlooked approaches and propose several new directions that have potential to improve the sensitivity, accuracy, and clinical utility of ToM measurement in autistic adulthood.

Why can some implicit Theory of Mind tasks be replicated and others cannot? A test of mentalizing versus submentalizing accounts

In the last 15 years, Theory of Mind research has been revolutionized by the development of new implicit tasks. Such tasks aim at tapping children’s and adults’ uninstructed, largely automatic mental state ascription, indicated in spontaneous looking behavior when observing agents who act on the basis of false beliefs. Studies with anticipatory looking, in particular, have suggested that basic ToM capacities operate from very early in life and remain in unconscious operation throughout the lifespan. Recently, however, systematic replication attempts of anticipatory looking measures have yielded a complex and puzzling mixture of successful, partial and non-replications. The present study aimed at shedding light on the question whether there is a system to this pattern. More specifically, in a set of three preregistered experiments, it was tested whether those conditions that could previously be replicated and those that could not differ in crucial conceptual respects such that the former do not strictly require ToM whereas the latter do. This was tested by the implementation of novel control conditions. The results were complex. There was generally no unambiguous evidence for reliable spontaneous ToM and no effect of the number of passed familiarization trials. Neither was there any unambiguous evidence that the previous mixed patterns of (non-)replications could be explained (away) by the sub-mentalizing account tested in the new control conditions. The empirical situation remains puzzling, and the question whether there is some such thing as implicit and spontaneous ToM remains to be clarified.

Repetitive TMS of the temporo-parietal junction disrupts participant's expectations in a spontaneous Theory of Mind task

A recent debate about Theory of Mind (ToM) concerns whether spontaneous and explicit mentalizing are based on the same mechanisms. However, only a few neuroimaging studies have investigated the neural bases of spontaneous ToM, with inconsistent results. The present study had two goals: first, to investigate whether the right Temporo-Parietal Junction (rTPJ) is crucially involved in spontaneous ToM and second, to gain insight into the role of the rTPJ in ToM. For the first time, we applied rTMS to the rTPJ while participants were engaged in a spontaneous false belief task. Participants watched videos of a scene including an agent who acquires a true or false belief about the location of an object. At the end of the movie, participants reacted to the presence of the object. Results show that, during stimulation of the control site, RTs were affected by both the participant's expectations and the belief of the agent. Stimulation of the rTPJ significantly modulated task performance, supporting the idea that spontaneous ToM, as well as explicit ToM, relies on TPJ activity. However, we did not observe a disruption of the representation of the agent's belief. Rather, the stimulation interfered with participant's predictions, supporting the idea that rTPJ is crucially involved in self-other distinction.

Abilities to Explicitly and Implicitly Infer Intentions from Actions in Adults with Autism Spectrum Disorder

Previous research suggests that Autism Spectrum Disorder (ASD) might be associated with impairments on implicit but not explicit mentalizing tasks. However, such comparisons are made difficult by the heterogeneity of stimuli and the techniques used to measure mentalizing capabilities. We tested the abilities of 34 individuals (17 with ASD) to derive intentions from others' actions during both explicit and implicit tasks and tracked their eye-movements. Adults with ASD displayed explicit but not implicit mentalizing deficits. Adults with ASD displayed typical fixation patterns during both implicit and explicit tasks. These results illustrate an explicit mentalizing deficit in adults with ASD, which cannot be attributed to differences in fixation patterns.

Spontaneous Theory of Mind is reduced for nonhuman-like agents as compared to human-like agents

Theory of Mind research has shown that we spontaneously take into account other's beliefs. In the current study, we investigate, with a spontaneous Theory of Mind (ToM) task, if this belief representation also applies to nonhuman-like agents. In a series of three experiments, we show here that we do not spontaneously take into account beliefs of nonhuman-like others, or at least we do it to a lesser extent than for human and human-like agents. Further, the experience we have with the other agent, in our case a dog, does not modulate spontaneous ToM: the same pattern of results was obtained when dog owners and no owners were compared. However, when more attention was attracted to the dog behavior, participants' behavior was influenced by the beliefs of the dog. In sum, spontaneous belief representation seems to be primarily restricted to human and human-like agents, but can be facilitated when more attention is drawn to a nonhuman-like agent.

Brain activity for spontaneous and explicit mentalizing in adults with autism spectrum disorder: An fMRI study

The socio-communicative difficulties of individuals with autism spectrum disorder (ASD) are hypothesized to be caused by a specific deficit in the ability to represent one's own and others' mental states, referred to as Theory of Mind or mentalizing. However, many individuals with ASD show successful performance on explicit measures of mentalizing, and for this reason, the deficit is thought to be better captured by measures of spontaneous mentalizing. While there is initial behavioral support for this hypothesis, spontaneous mentalizing in ASD has not yet been studied at the neural level. Recent findings indicate involvement of the right temporoparietal junction (rTPJ) in both explicit and spontaneous mentalizing (Bardi et al., 2016). In the current study, we investigated brain activation during explicit and spontaneous mentalizing in adults with ASD by means of fMRI. Based on our hypothesis of a core mentalizing deficit in ASD, decreased rTPJ activity was expected for both forms of mentalizing. A group of 24 adults with ASD and 21 neurotypical controls carried out a spontaneous and an explicit version of the same mentalizing task. They watched videos in which both they themselves and another agent formed a belief about the location of an object (belief formation phase). Only in the explicit task version participants were instructed to report the agent's belief on some trials. At the behavioral level, no group differences were revealed in either of the task versions. A planned region-of-interest analysis of the rTPJ showed that this region was more active for false- than for true-belief formation, independent of task version, especially when the agent's belief had a positive content (when the agent was expecting the object). This effect of belief was absent in adults with ASD. A whole-brain analysis revealed reduced activation in the anterior middle temporal pole in ASD for false - versus true-belief trials, independent of task version. Our findings suggest neural differences between adults with ASD and neurotypical controls both during spontaneous and explicit mentalizing, and indicate the rTPJ to be crucially involved in ASD. Moreover, the possible role of the anterior middle temporal pole in disturbed mentalizing in ASD deserves further attention. The finding that these neural differences do not necessarily lead to differential performance warrants further research.

Spontaneous mentalizing in neurotypicals scoring high versus low on symptomatology of autism spectrum disorder

Spontaneous mentalizing ability has been linked to symptoms severity in individuals with autism spectrum disorder (ASD). Here we investigated whether in neurotypicals, higher levels of ASD symptomatology could also be linked to lower levels of spontaneous mentalizing, by comparing neurotypicals scoring high with those scoring low on the short Autism Spectrum Quotient. Participants watched movies during which they, and another agent, formed beliefs about the location of an object. These beliefs could influence reaction times (RT) to that object in the outcome phase. We expected participants with more ASD symptoms to show less spontaneous mentalizing, as reflected by a smaller effect of the other agent's beliefs on RT patterns (the ToM index). In contrast, the effect of own beliefs on RTs, reflecting an egocentric bias, was expected to be larger in the high-scoring group. Results showed that groups differed in the effect of the agent's beliefs; the ToM index was highly significant in the low-scoring group, while being absent in the high-scoring group. No difference in egocentric bias was observed. These findings suggest that the relationship between levels of ASD symptomatology and spontaneous mentalizing is not only present in individuals with ASD, but also in the neurotypical population.

Brain activation for spontaneous and explicit false belief tasks overlaps: new fMRI evidence on belief processing and violation of expectation

There is extensive discussion on whether spontaneous and explicit forms of ToM are based on the same cognitive/neural mechanisms or rather reflect qualitatively different processes. For the first time, we analyzed the BOLD signal for false belief processing by directly comparing spontaneous and explicit ToM task versions. In both versions, participants watched videos of a scene including an agent who acquires a true or false belief about the location of an object (belief formation phase). At the end of the movies (outcome phase), participants had to react to the presence of the object. During the belief formation phase, greater activity was found for false vs true belief trials in the right posterior parietal cortex. The ROI analysis of the right temporo-parietal junction (TPJ), confirmed this observation. Moreover, the anterior medial prefrontal cortex (aMPFC) was active during the outcome phase, being sensitive to violation of both the participant’s and agent’s expectations about the location of the object. Activity in the TPJ and aMPFC was not modulated by the spontaneous/explicit task. Overall, these data show that neural mechanisms for spontaneous and explicit ToM overlap. Interestingly, a dissociation between TPJ and aMPFC for belief tracking and outcome evaluation, respectively, was also found.