Do 10-month-old infants understand others' false beliefs?

As adults, we know that others’ mental states, such as beliefs, guide their behavior and that these mental states can deviate from reality. Researchers have examined whether young children possess adult-like theory of mind by focusing on their understanding about others’ false beliefs. The present research revealed that 10-month-old infants seemed to interpret a person’s choice of toys based on her true or false beliefs about which toys were present. These results indicate that like adults, even preverbal infants act as if they can consider others’ mental states when making inferences about others’ actions.     

The relations between children's communicative perspective-taking and executive functioning

Two experiments investigated children’s communicative perspective-taking ability. In Experiment 1, 4- to 5-year-old children were tested on two referential communication tasks, as well as on measures of inhibitory control, working memory, and cognitive flexibility. Results document children’s emergent use of the perspective of their speaking partner to guide their communicative behaviors in both a production and comprehension task. In Experiment 2, 3- to 4-year-old children used a speaker’s perspective to guide their interpretation of instructions. In both experiments, egocentric interpretations of speaker requests were negatively correlated with children’s inhibitory control skills. Results of these studies demonstrate that young children can differentiate between information that is accessible to the speaker versus privileged knowledge, and use this information to guide their communicative behaviors. Furthermore, the results suggest that children’s inhibitory control skills allow them to inhibit their own perspective, enabling them to make use of their communicative partner’s perspective.     

Stereotyped beliefs about desirability: implications for characterizing the child's theory of mind

A central research issue in the child's theory of mind literature is the question of whether children appreciate the subjectivity of mental phenomena. The typical research paradigm involves researchers creating a discrepancy between children's own mental states and the mental state of a protagonist, and then asking children to predict the protagonist's reaction. A prediction that fits the child's own mental state (rather than the beliefs and desires of the protagonist) is seen as an indication that the child fails to acknowledge the subjectivity of mental phenomena.Here we present two experiments involving the use of desire statements in predicting other people's emotions which demonstrate that even when one does acknowledge the subjectivity of mental states, this does not necessarily leads to ‘correct’ predictions (e.g. predictions based on the protagonist's desires). Other factors, such as cultural knowledge, might influence this process. The first experiment demonstrates that even adults, with a fully operational theory of mind, sometimes choose to disregard information about other people's desires. Their own generalized beliefs about desirability appear to be instrumental in this respect. The second experiment, on sex-stereotyped preferences for toys, demonstrates that even young children already can use generalized beliefs about desirability as a basis for their predictions of others’ emotions, even when these beliefs on desirability do not coincide with their own desires. This strategy results in a response pattern that can be easily misconceived as an indication that the child does not yet appreciate the subjectivity of desires.Two remarks are made on the basis of these experiments. First, even a so-called ‘adult’ theory of mind tends to be affected by normative considerations and is therefore more complex than straightforward desire-belief reasoning. Second, whenever normative considerations come into play, researchers should be cautious that ‘correct’ answers in theory of mind testing may not always have been based on theory of mind reasoning, and that ‘incorrect’ answers do not necessarily imply the absence of an active theory of mind.     

I see into your mind too well: working memory adjusts the probability judgment of others' mental states

Although an increasing number of studies on adults have indicated that working memory (WM) contributes to the ability to understand the mental states of others (i.e., theory of mind), the detailed mechanism by which WM contributes to successful reasoning has not previously been revealed. This study shows that WM modulates the degree of attribution of one's own knowledge to others' mental states. Participants were asked to read a story twice (Experiment 2) or as carefully as possible (Experiment 3) and to estimate the probability percentages of possible choices for a naive protagonist's behavior. The participants were then asked to maintain either a two- or seven-letter alphabet string (i.e., a light or heavy WM load, respectively) during the probability estimation but not during the story comprehension. The results showed that compared to the participants with a light WM load, those with a heavy WM load estimated a significantly higher probability of the choice indicating that the protagonist would behave on the basis of a fact that the participants knew but the protagonist did not. This result indicates that WM moderates the extent to which adults attribute their own knowledge to others' mental states. The role of WM in theory of mind and in heuristic strategy for making probability judgments was then discussed.     

To belief or not belief: Children’s theory of mind

This paper provides a minimalist framework for understanding the development of children’s theory of mind (ToM). First, I provide a critical analysis of rich interpretations of ToM tasks tapping infants’ understanding of perception, goals, intentions, and false beliefs. I argue that the current consensus that infants understand mental states is premature, and instead, that excellent statistical learning skills and attention to human faces and motion enable infants’ very good performance, and reflect an implicit understanding of behavior. Children subsequently develop an explicit understanding of mental states through talk from parents and siblings, their developing language abilities, and their developing distinction between self and other. The paper also examines corollary theories such as the idea that there are subsystems of a theory of mind (ToM), that infants use rules on false belief tasks, that minimalist theory is post hoc, and that parallel onset of success on different ToM tasks indicates an underlying ToM. The paper concludes by considering previous arguments against minimalist interpretations of infant performance.     

It’s in your nature: a pluralistic folk psychology

I suggest a pluralistic account of folk psychology according to which not all predictions or explanations rely on the attribution of mental states, and not all intentional actions are explained by mental states. This view of folk psychology is supported by research in developmental and social psychology. It is well known that people use personality traits to predict behavior. I argue that trait attribution is not shorthand for mental state attributions, since traits are not identical to beliefs or desires, and an understanding of belief or desire is not necessary for using trait attributions. In addition, we sometimes predict and explain behavior through appeal to personality traits that the target wouldn’t endorse, and so could not serve as the target’s reasons. I conclude by suggesting that our folk psychology includes the notion that some behavior is explained by personality traits—who the person is—rather than by beliefs and desires—what the person thinks. Consequences of this view for the debate between simulation theory and theory theory, as well as the debate on chimpanzee theory of mind are discussed.     

Enabling conditions and children’s understanding of pretense

Two experiments examined whether preschoolers’ difficulties on tasks that required relating pretending and knowledge (e.g., Lillard, A. S. (1993a). Young children’s conceptualization of pretense: Action or mental representational state? Child Development, 64, 372-386) were due to children’s inability to appreciate the causal mechanism behind enabling conditions. In Experiment 1, 4-year-olds were told about a character who knew about one kind of animal and did not know about another. The character acted in a manner consistent with both animals. Children were asked whether the character was pretending to be the animal of which he was ignorant. The character’s knowledge was either represented in a generic manner (as a picture) or in a manner that suggested a particular enabling condition relation that children found accessible (as a battery, which most 4-year-olds recognize is critical for making toys work). Children were more successful at relating knowledge and pretending in the battery condition. This improvement in performance extended to another task in which children had to identify the enabling condition relation between knowledge and identification, in which there were reduced demands on the inhibitory mechanisms necessary for success. Experiment 2 found that the results in Experiment 1 were not due to demands of the procedure used in Experiment 1. These results are discussed in the context of recent theories of theory of mind that focus on the importance of causal relations among mental states.     

Belief-based action prediction in preverbal infants

Successful mindreading entails both the ability to think about what others know or believe, and to use this knowledge to generate predictions about how mental states will influence behavior. While previous studies have demonstrated that young infants are sensitive to others’ mental states, there continues to be much debate concerning how to characterize early theory of mind abilities. In the current study, we asked whether 6-month-old infants appreciate the causal role that beliefs play in action. Specifically, we tested whether infants generate action predictions that are appropriate given an agent’s current belief. We exploited a novel, neural indication of action prediction: motor cortex activation as measured by sensorimotor alpha suppression, to ask whether infants would generate differential predictions depending on an agent’s belief. After first verifying our paradigm and measure with a group of adult participants, we found that when an agent had a false belief that a ball was in the box, motor activity indicated that infants predicted she would reach for the box, but when the agent had a false belief that a ball was not in the box, infants did not predict that she would act. In both cases, infants based their predictions on what the agent, rather than the infant, believed to be the case, suggesting that by 6 months of age, infants can exploit their sensitivity to other minds for action prediction.     

The link between preschoolers' executive function and theory of mind and the role of epistemic states

The aim of this study was to assess the specific relation between 3- to 6-year-olds’ performance on a task measuring executive function (EF), the Dimensional Change Card Sort task (DCCS), and different developmental attainments in their theory of mind (ToM) by employing a battery of scaled ToM tasks that were comparable in task format and task demands. In addition, individual differences on the temperamental dimensions emotionality, activity, sociability, and shyness were assessed by parental rating. The main findings show that children’s (N = 195) performance on the DCCS related to their overall performance on the ToM scale but that this relation was specific to those ToM tasks that tap children’s understanding of epistemic states such as knowledge access, diverse beliefs, and false beliefs regarding content and location. The relation between children’s EF and overall ToM performance remained significant after controlling for age, sentence comprehension, child temperament, and parental education. Individual differences in child activity showed consistent negative relation to EF and ToM abilities. The findings point to a differential involvement of the various EF components in reasoning about different mental concepts.     

Action understanding as inverse planning

Humans are adept at inferring the mental states underlying other agents’ actions, such as goals, beliefs, desires, emotions and other thoughts. We propose a computational framework based on Bayesian inverse planning for modeling human action understanding. The framework represents an intuitive theory of intentional agents’ behavior based on the principle of rationality: the expectation that agents will plan approximately rationally to achieve their goals, given their beliefs about the world. The mental states that caused an agent’s behavior are inferred by inverting this model of rational planning using Bayesian inference, integrating the likelihood of the observed actions with the prior over mental states. This approach formalizes in precise probabilistic terms the essence of previous qualitative approaches to action understanding based on an “intentional stance” [Dennett, D. C. (1987). The intentional stance. Cambridge, MA: MIT Press] or a “teleological stance” [Gergely, G., Nádasdy, Z., Csibra, G., & Biró, S. (1995). Taking the intentional stance at 12 months of age. Cognition, 56, 165-193]. In three psychophysical experiments using animated stimuli of agents moving in simple mazes, we assess how well different inverse planning models based on different goal priors can predict human goal inferences. The results provide quantitative evidence for an approximately rational inference mechanism in human goal inference within our simplified stimulus paradigm, and for the flexible nature of goal representations that human observers can adopt. We discuss the implications of our experimental results for human action understanding in real-world contexts, and suggest how our framework might be extended to capture other kinds of mental state inferences, such as inferences about beliefs, or inferring whether an entity is an intentional agent.     

Destination memory and cognitive theory of mind in normal ageing

Destination memory is the ability to remember the destination to which a piece of information has been addressed (e.g., “Did I tell you about the promotion?”). This ability is found to be impaired in normal ageing. Our work aimed to link this deterioration to the decline in theory of mind. Forty younger adults (M age = 23.13 years, SD = 4.00) and 36 older adults (M age = 69.53 years, SD = 8.93) performed a destination memory task. They also performed the False-belief test addressing cognitive theory of mind and the Reading the mind in the eyes test addressing affective theory of mind. Results showed significant deterioration in destination memory, cognitive theory of mind and affective theory of mind in the older adults. The older adults’ performance on destination memory was significantly correlated with and predicted by their performance on cognitive theory of mind. Difficulties in the ability to interpret and predict others’ mental states are related to destination memory decline in older adults.     

(Why) do I think what you think? Epistemic social tuning and implicit prejudice

This research examines whether people who experience epistemic motivation (i.e., a desire to acquire knowledge) came to have implicit attitudes consistent with the apparent beliefs of another person. People had lower implicit prejudice when they experienced epistemic motivation and interacted with a person who ostensibly held egalitarian beliefs (Experiments 1 and 2). Implicit prejudice was not affected when people did not experience epistemic motivation. Further evidence shows that this tuning of implicit attitudes occurs when beliefs are endorsed by another person, but not when they are brought to mind via means that do not imply that person's endorsement (Experiment 3). Results suggest that implicit attitudes of epistemically motivated people tune to the apparent beliefs of others to achieve shared reality.     

The influence of depression symptoms on exploratory decision-making

People with symptoms of depression show impairments in decision-making. One explanation is that they have difficulty maintaining rich representations of the task environment. We test this hypothesis in the context of exploratory choice. We analyze depressive and non-depressive participants’ exploration strategies by comparing their choices to two computational models: (1) an “Ideal Actor” model that reflectively updates beliefs and plans ahead, employing a rich representation of the environment and (2) a “Naïve Reinforcement Learning” (RL) model that updates beliefs reflexively utilizing a minimal task representation. Relative to non-depressive participants, we find that depressive participants’ choices are better described by the simple RL model. Further, depressive participants were more exploratory than non-depressives in their decision-making. Depressive symptoms appear to influence basic mechanisms supporting choice behavior by reducing use of rich task representations and hindering performance during exploratory decision-making.     

Thinking about seeing: Perceptual sources of knowledge are encoded in the theory of mind brain regions of sighted and blind adults

Blind people’s inferences about how other people see provide a window into fundamental questions about the human capacity to think about one another’s thoughts. By working with blind individuals, we can ask both what kinds of representations people form about others’ minds, and how much these representations depend on the observer having had similar mental states themselves. Thinking about others’ mental states depends on a specific group of brain regions, including the right temporo-parietal junction (RTPJ). We investigated the representations of others’ mental states in these brain regions, using multivoxel pattern analyses (MVPA). We found that, first, in the RTPJ of sighted adults, the pattern of neural response distinguished the source of the mental state (did the protagonist see or hear something?) but not the valence (did the protagonist feel good or bad?). Second, these neural representations were preserved in congenitally blind adults. These results suggest that the temporo-parietal junction contains explicit, abstract representations of features of others’ mental states, including the perceptual source. The persistence of these representations in congenitally blind adults, who have no first-person experience with sight, provides evidence that these representations emerge even in the absence of relevant first-person perceptual experiences.     

Theory of mind enhances preference for fairness

The purpose of the current study was to examine the role of theory of mind in fairness-related behavior in preschoolers and to introduce a tool for examining fairness-related behavior in children. A total of 68 preschoolers played the Ultimatum Game in a face-to-face setting. Acquisition of theory of mind was defined as the understanding of false beliefs using the Sally-Anne task. The results showed that preschoolers who had acquired theory of mind proposed higher mean offers than children who had not acquired theory of mind. These findings imply that the ability to infer the mental states of others plays an important role in fairness-related behavior.     

Interpretive sensory-access theory and conscious intentions

It is typically assumed that while we know other people's mental states by observing and interpreting their behavior, we know our own mental states by introspection, i.e., without interpreting ourselves. In his latest book, The opacity of mind: An integrative theory of self-knowledge, Peter Carruthers [2011. The opacity of mind: An integrative theory of self-knowledge. Oxford: Oxford University Press] argues against this assumption. He holds that findings from across the cognitive sciences strongly suggest that self-knowledge of conscious propositional attitudes such as intentions, judgments, and decisions involves a swift and unconscious process of self-interpretation that utilizes the same sensory channels that we employ when working out other people's mental states. I provide an overview of Carruthers’ book before discussing a pathological case that challenges his account of self-knowledge and mentioning empirical evidence that undermines his use of a particular kind of data in his case against introspection of conscious attitudes.     

Developing organization of mental verbs: Evidence for the development of a constructivist theory of mind in middle childhood

Two experiments examined the development of a theory of mind in middle childhood by examining changes in the organization of mental verbs of knowing. In both experiments, children and adults rated the similarity of pairs of mental verbs in terms of the way they felt they used their mind in each one. Experiment 1 used thirty-six 8- and thirty-four 10-year-olds, and 27 adults. In Experiment 2, 9- and 11-year-old children were classified according to their cognitive monitoring ability (Markman, 1981). Fifteen cognitive monitoring and 15 nonmonitoring children were used, and 33 adults also participated. Multidimensional scaling (MDS) analyses of each group's ratings indicated that participants distinguished mental verbs according to the certainty aspects and information processing aspects of mental activity. Older children and comprehension monitors placed greater emphasis on the certainty aspects of mental activity than younger children and comprehension nonmonitors. It is concluded that important aspects of a constructivist theory of mind develop during middle childhood.     

The personalisation method applied to a working memory task: Evidence of long-term working memory effects

Ericsson and Kintsch (1995) proposed that, in situations of expertise, individuals can overcome working memory limitations by using long-term working memory. It allows a greater capacity than working memory thanks to long-term memory encoding and retrieving. To test this characteristic, an adaptation of Daneman and Carpenter's (1980) reading span was used. To operationalise expertise, the personalisation method (Guida & Tardieu, 2005) was employed. In Experiment 1, a personalised group, which read reading span sentences that mentioned familiar locations, was compared to a nonpersonalised group, which read sentences with unfamiliar locations. In Experiment 2, a personalised group, which read reading span sentences with neutral locations, was encouraged to mentally personalise these locations by thinking about known locations. This group was compared to a nonpersonalised group, which was encouraged to think about unknown locations. The personalised groups were expected to store and retrieve information in long-term memory via long-term working memory more easily than the nonpersonalised groups, which had to count massively on working memory. The results showed that personalisation enhanced reading span and confirmed one implication of the long-term working memory theory: high- and low-reading-span differences could also be due to long-term memory retrieval. Finally, these results are interpreted in terms of interaction between working memory size and long-term memory knowledge, showing that participants with a lower reading span benefited more from high domain knowledge than participants with a higher reading span.