Previous research has shown that 2.5-year-old toddlers succeed at a verbal false belief (FB) task when response generation and inhibitory control demands were reduced (Setoh et al., 2016). However, this low-inhibition version of a traditional FB task was criticized for being susceptible to low-level strategies, such as pointing to the last location where the object had been, rather than inferring the agent’s belief. To rule out such alternative explanations, we extended the Setoh et al. (2016) paradigm by adding a second condition (FB=first) where the location the agent believed the object to be was its first location. German (N=56) and Chinese (N=45) 3- to 5-year-olds were tested with this extended low-demand FB task, a standard FB task, and an inhibitory control task. Across both cultures, children performed well in the original FB=last condition from age 3, but only passed the new FB=first condition around age 5. Performance in the FB=first condition was related to age and performance in the standard FB task, while the FB=last condition was not. The discrepancy between FB=first and FB=last condition suggests that young children’s success in the original study by Setoh et al. (2016) was due to the non-mentalistic strategy of choosing the last object location. Our findings are consistent across two cultures, suggesting that, in line with the traditional theory, explicit false belief reasoning emerges around age 4 in both Western and Chinese cultures, even when the executive demands of the task are reduced.

Abstract Two questions about the book are asked. Why it deals with perspective and why with mental files. Perspective taking is important for various vagaries of life and raises interesting theoretical issues of word meaning and opens the way of going beyond the real and think of its appearances and worlds of fiction. Mental files are the choice of method not only for addressing issues of perspective but as a general tool for capturing how our mind structures the world into persisting objects with changeable properties, and for tracking objects over time and collecting knowledge about them. Having more than one file (coreferential files) of the same object allows for different perspectives on that object and to represent other people’s views. It provides a grass roots approach to understanding the mind and human action. The files also provide a coherent characterisation of ‘perspective tasks’. Although these tasks pertain to quite different domains of knowledge children master them all between the ages of 3 to 5 years, which challenges the view that cognitive development is domain specific.

Scenarios of sabotage were used to investigate children's appreciation of desires as subjective attitudes. Fifty-one pre-schoolers showed high proficiency in inferring an action in a cooperative scenario where two agents had a common goal and intended to coordinate goal achievement. However, they were at chance in inferring an action in a competitive scenario where two agents had a conflict of values and one intended to sabotage the others' goal achievement. Moreover, understanding of sabotage was correlated with false belief understanding after controlling for age, verbal ability, working memory, inhibitory control, and planning. This result suggests a symmetrical development of understanding beliefs and desires by means of subjective attitudes as predicted by Perner and Roessler's teleological theory of action explanation. As soon as children are able to understand perspectives, they appreciate false beliefs as well as conflicting values as reasons for actions.

Do toddlers and adults engage in spontaneous Theory of Mind? This multi-lab collaboration examined whether 18- to 27-month-olds’ and adults’ anticipatory looks distinguish between two basic forms of epistemic states: knowledge and ignorance. In adults (n = 703, 68% female), we found clear evidence that they do: they showed simple goal-based action anticipation in pilot studies and differentiated between knowledge and ignorance conditions in the main study. In toddlers (n = 521, 49% female), results were less conclusive. While demonstrating goal-based action anticipation in pilot studies, they did not differentiate between knowledge and ignorance as predicted. Future research can explore adults’ sensitivity to more complex epistemic states like true/false beliefs and clarify whether toddlers’ results reflect competence or performance limitations.

The present study systematically investigated how 83 (42 female, Austrian, 41 to 79 months) children reasoned on Call and Tomasello's (1999) nonverbal false belief task. Experiment 1 replicated the central finding that children realized that a mistaken communicator tended to mark the wrong, unbaited box. However, we found that less than half of the children gave consistently correct responses while others responded in a way indistinguishable from random guessing. Some children noted that markings were consistently wrong, suggesting a simple response strategy of choosing the unmarked box without reasoning about the communicator's false belief. Experiment 2 undermined this potential strategy by adding correctly marked trials. Performance dropped so that it could not be distinguished anymore from random responding. These results call into question whether Call and Tomasello's task detects reasoning about false beliefs.

Neuroscience has examined the brain processes of recognizing and identifying a known person. But the process of integrating the representation of a temporarily unrecognised person with the representation of the familiar person is not yet known (e.g., as in Mandler's butcher on the bus). This process is one of identification; the stranger (man on the bus) has to be seen as identical to the old acquaintance (butcher from the supermarket). Our fMRI experiment contrasts this case of belated recognition with immediate recognition. The results show stronger activation of left inferior parietal lobe (IPL) and the left anterior temporal lobe (ATL) for identification over pure recognition. The data are discussed under the mental files framework providing an important extension to current person recognition paradigms.

Level 1 visuo-spatial perspective-taking (VSPT) refers to judging what other people can and cannot see. Previous research has suggested that this form of VSPT can be achieved relatively effortlessly. Level 2 VSPT, which refers to judgments about how an object appears from different viewpoints, is conceptually more complex and linked to higher-level social cognition and mentalizing. Despite growing neuroscientific evidence on VSPT, fMRI studies have not yet directly compared levels of perspective-taking. Study 1 collected fMRI data from a within-subject comparison of level 2 versus level 1 VSPT. We used a common activation contrast comparing inconsistent versus consistent perspectives between self and others. In Study 2, we further distinguished the brain regions associated with level 2 VSPT from those responsive to stimulus ambiguity and complexity. To achieve this, we asked participants to adopt different viewpoints on ambiguous and unambiguous stimuli. Results from both studies found that brain activation for level 2 VSPT was particularly high in areas of the dorsal attention network. Follow-up connectivity analysis found that level 2 VSPT is primarily carried out by the dorsal attention and the frontoparietal network. These results align with theories suggesting that VSPT can be achieved by engaging visuospatial attention and inhibitory control processes.

The terminology used in discussions on mental state attribution is extensive and lacks consistency. In the current paper, experts from various disciplines collaborate to introduce a shared set of concepts and make recommendations regarding future use.

The standard view on explicit theory of mind development holds that children around the age of 4 years start to ascribe beliefs to themselves and others, typically tested with false belief (FB) tasks. The present study (N = 95, 53 female, 41 male, Austrian, 41 to 80 months) systematically investigated the puzzling phenomenon that FB achievers (FB+) fail knowledge (often subsumed under "true belief") tasks: Despite the story protagonist witnessing the displacement of an object these children predict that the protagonist will look for it in its original location. We replicate this result in Experiment 1. Interestingly, some of our children indicated uncertainty about the protagonist's awareness of the relevant event. Thus, in Experiment 2 a new active watching condition was designed to help children understand that the protagonist attended to the critical event. This practically eradicated the knowledge error. Experiment 3 successfully replicated these results. Implications for existing explanations, perceptual access reasoning (PAR, Fabricius, Boyer, Weimer, & Carroll, 2010) and pragmatic difficulties (Oktay-Gür & Rakoczy, 2017) are discussed.

The first part of this chapter focuses on the development of our theory of mind or folk psychology. The second part gives a brief overview of how counterfactual reasoning develops and how this development interacts with theory of mind development. In both parts our focus is on developmental research that speaks to basic issues: What is the nature of our folk psychology, its genetic or experiential basis, its kinship with executive control and pragmatics, and its cognitive mechanism? Is there an ‘implicit’ theory that even infants master? How does counterfactual reasoning differ from conditional reasoning and why should counterfactual reasoning be important for folk psychology? We examine what answers forty years of research have produced so far.

The litmus test for the development of a metarepresentational Theory of Mind is the false belief (FB) task in which children have to represent how another agent misrepresents the world. Children typically start mastering this task around age four. Recently, however, a puzzling finding has emerged: Once children master the FB task, they begin to fail true belief (TB) control tasks. Pragmatic accounts assume that the TB task is pragmatically confusing because it poses a trivial academic test question about a rational agent's perspective; and we do not normally engage in such discourse about subjective mental perspectives unless there is at least the possibility of error or deviance. The lack of such an obvious possibility in the TB task implicates that there might be some hidden perspective difference and thus makes the task confusing. In the present study, we test the pragmatic account by administering to 3- to 6-year-olds (N = 88) TB and FB tasks and structurally analogous true and false sign (TS/FS) tasks. The belief and sign tasks are matched in terms of representational and metarepresentational complexity; the crucial difference is that TS tasks do not implicate an alternative non-mental perspective and should thus be less pragmatically confusing than TB tasks. The results show parallel and correlated development in FB and FS tasks, replicate the puzzling performance pattern in TB tasks, but show no trace of this in TS tasks. Taken together, these results speak in favor of the pragmatic performance account.

Do toddlers and adults engage in spontaneous Theory of Mind (ToM)? Evidence from anticipatory looking (AL) studies suggests that they do. But a growing body of failed replication studies raised questions about the paradigm’s suitability. In this multi-lab collaboration, we test the robustness of spontaneous ToM measures. We examine whether 18- to 27-month-olds’ and adults’ anticipatory looks distinguish between two basic forms of an agent’s epistemic states: knowledge and ignorance. In toddlers [ANTICIPATED n = 520 50% FEMALE] and adults [ANTICIPATED n = 408, 50% FEMALE] from diverse ethnic backgrounds, we found [SUPPORT/NO SUPPORT] for epistemic state-based action anticipation. Future research can probe whether this conclusion extends to more complex kinds of epistemic states, such as true and false beliefs.

Comparing knowledge with belief can go wrong in two dimensions: If the authors employ a wider notion of knowledge, then they do not compare like with like because they assume a narrow notion of belief. If they employ only a narrow notion of knowledge, then their claim is not supported by the evidence. Finally, we sketch a superior teleological view.

With their Duplo task, Rubio-Fernandez and Geurts (2013) challenged the assumption that children under 4 years of age cannot pass the standard false belief test. In an attempt to replicate this task on a sample of 73 children aged 32-51 months, we added a standard change of location false belief task as well as a Duplo true belief task. Performance on the latter is crucial for interpreting answers in the Duplo false belief task as to whether they reflect evidence for understanding or merely exhibit a difference in guessing rate. We found (a) a greater variability of response types in both Duplo tasks, (b) no evidence that responses in the Duplo tasks reveal earlier competence than those in the standard false belief test, and (c) a reassuring correlation between false belief tasks, suggesting that the Duplo task does pick up understanding of belief in light of the standard test. (C) 2019 The Authors. Published by Elsevier Inc.