Theory of mind, the ability to attribute mental states to oneself and others, has traditionally been investigated in humans and nonhuman primates. However, non-primate species, such as domestic dogs, may also be potential candidates for such a faculty. Domestic dogs (Canis familiaris) evolved from a social-living, wolf-like ancestor, and were the first species to be domesticated, with likely selection for sensitivity to human cues and human-like cognitive abilities. Dogs typically spend their lives in the rich social environment of human families, and thus dogs are naturally enculturated. The combination of these factors make dogs an excellent candidate for having a functional theory of mind. Yet perhaps surprisingly, prior research on theory of mind in dogs is limited, with inconclusive and contradictory results. The research described in this thesis is a systematic investigation of dogs' potential to demonstrate a functional theory of mind in their interactions with humans. Four experiments are presented, based on the Knower-Guesser paradigm (Povinelli et al., 1990), in which a knowledgeable and an ignorant human informant indicated the location of hidden food to the dog. In Experiment 1, one informant was absent (Guesser) and one present (Knower) during the food-hiding, and the dogs chose the Knower. However, when both informants were present, the dogs chose the informant that did the baiting, but this preference was less than when the Guesser was absent. In Experiments 2 and 3, a third experimenter hid the food while the informants covered their cheeks (Knower) or eyes (Guesser) with their hands, or were attentive (Knower) or inattentive (Guesser) to the food-hiding. In both cases, the dogs showed a significant preference for the Knower. In Experiment 4, the dogs showed no preference between the informants when they had equal perceptual access to the baiting, and were unsuccessful at selecting any container when the informants did not provide communicative cues. Overall, the present research provides the most definitive evidence yet that domestic dogs may be able to attribute differential states of knowledge to human observers, and thus may possess a functional theory of mind.

Recent functional neuroimaging evidence suggests that recalling autobiographical memories, imagining fictitious autobiographical episodes, and taking the perspective of another person activate a similar network of brain regions. Results from the two studies presented here provide further evidence of this common neural network. Previous evidence also suggests that recalling autobiographical memories from a first person or from a third person perspective can influence the way in which those memories are experienced as well as the brain regions that are engaged; however, the effect of perspective on imagining autobiographical events remains unclear. Results from Study 1 indicated that brain regions implicated in both remembering and imagining were differentially engaged during these tasks depending on whether a first person or a third person perspective was taken. In addition, while recalling autobiographical memories from a third person perspective can result in the feeling that a past self is more like another person, imagining oneself in the position of another person can result in the feeling that that person is more similar to oneself; this suggests a possible link between perspective in memory and social perspective taking. In Study 2, we identified several brain regions exhibiting a pattern of increasing or decreasing activation as a function of whether socially interactive events were recalled from a first person perspective, by imagining oneself as one's partner, or from a third person perspective (i.e., as a function of distance from one's own perspective). Together, our findings suggest that perspective plays an important role in the way in which brain regions that are part of this common neural network are engaged during memory, imagination, and socially interactive tasks.

When evaluating a situation that results in harm, it is critical to consider how a person’s prior intention may have been causally responsible for the action that resulted in the harmful outcome. This thesis examined children’s developing understanding of intentional causation in reasoning about harmful outcomes, and the relation between this understanding and mental-state reasoning. Four-, 6-, and 8-year-old children, and adults, were told eight stories in which characters’ actions resulted in harmful outcomes. Story types differed in how the actions that resulted in harm were causally linked to their prior intentions such that: (1) characters wanted to, intended to, and did perform a harmful act; (2) they wanted and intended to perform a harmful act, but instead, accidentally brought about the harmful outcome; (3) they wanted and intended to perform a harmful act, then changed their mind, but accidentally brought about the harmful outcome; (4) they did not want or intend to harm, but accidentally brought about a harmful outcome. Participants were asked to judge the characters’ intentions, make punishment judgments, and justify their responses. Additionally, children were given first- and second-order false-belief tasks, commonly used to assess mental-state reasoning. The results indicated that intention judgment accuracy improved with age. However, all age groups had difficulty evaluating the intention in the deviant causal chain scenario (Searle, 1983), in which the causal link between intention and action was broken but a harmful intention was maintained. Further, the results showed a developmental pattern in children’s punishment judgments based on their understanding of intentional causation, although the adults’ performance did not follow the same pattern. Also, younger children referred to the characters’ intentions less frequently in their justifications of their punishment judgments. The results also revealed a relation between belief-state reasoning and intentional-causation reasoning in scenarios that did not involve, or no longer involved, an intention to harm. Further, reasoning about intentional causation was related to higher-level understanding of mental states. The implications of these findings in clarifying and adding to previous research on the development of understanding of intentional causation and intentions in moral reasoning are discussed.

To date, there is compelling evidence to show that theory-of-mind development is influenced by different environmental and cognitive factors. However, despite our understanding of the different individual processes that facilitate theory-of-mind acquisition, what remains relatively unclear is how these processes operate together during development. The goal of the present dissertation is to examine mediation (examines the relationship between two different factors and address the question of “why” or “how” one variable predicts or causes an outcome variable) and moderation (examines “when” or “for whom” a variable most strongly predicts or causes an outcome variable) processes that can help explain why and under what conditions environmental and cognitive factors are important for theory-of-mind development. The investigation began by examining the influence of environmental factors on theory-of-mind development. Mediation analyses were used to examine “why” environmental factors such as family (i.e., family risk) and socio-linguistic factors (i.e., parental cognitive talk), may be important for theory-of-mind development. Preliminary results demonstrated possible mediated effects of both family risk and parental cognitive talk on theory of mind. That is, family risk may delay children’s theory-of-mind development by impeding the rate of language acquisition, whereas parental cognitive talk may facilitate more advanced theory-of-mind understanding by encouraging more parent-child reciprocity during conversations. Next, the effects of cognitive factors on theory-of-mind development were explored. Moderation analysis was used to examine under what conditions children’s language abilities and conflict inhibition skills (children’s ability to inhibit a prepotent response while responding with a less salient response) are important for theory-of-mind acquisition. Although there may be limited effects of child language and conflict inhibition on early theory of mind, advanced theory-of-mind understanding such as false belief requires both. However, optimal effects of child language on false-belief understanding occurred when children also had high levels of conflict inhibition ability. These findings suggest that effects of child language on false belief are contingent on children’s conflict inhibition skills. Finally, to investigate how environmental and cognitive factors operate together during theory-of-mind development, moderation analysis was conducted to examine whether delays in language and/or conflict inhibition can be compensated for by more exposure to parental cognitive talk (and vice versa) during theory-of-mind acquisition. Although there was no evidence to suggest compensatory effects, results demonstrated that child language and parental cognitive talk both independently contributed to theory of mind. These findings suggest that environmental (e.g., parental cognitive talk) and cognitive factors (e.g., child language) play distinct roles during theory-of-mind development. Overall, these results demonstrate the value of understanding theory-of-mind development from a bioecological perspective where children are both directly and indirectly influenced by multiple mechanisms during theory-of-mind development.

The ability to represent the mental states of others (i.e., Theory of Mind, ToM) is vital for social interaction. There is limited information on ToM knowledge in children with specific language impairment (SLI). These children have deficient language abilities that cannot be explained by hearing, cognitive, or neurological problems. Furthermore, children with SLI experience difficulty in initiating and maintaining social pretend play. Language, pretend play, and ToM typically develop in concert, which may indicate that they share an underlying capacity for representation. Given that language is deficient in children with SLI, these children may have problems with ToM, which might be related to their social behaviors during pretend play. This study was the first to investigate the association between ToM and pretend play in children with and without SLI. Twenty-two children with SLI and 22 with typical development (TD), between 48-71 months of age, participated in this study. Children engaged in a variety of ToM tasks and participated in two pretend play assessments: a standardized pretend play assessment and a role play activity. Children with SLI scored significantly lower on ToM tasks and engaged less often in some sophisticated forms of pretend play than their age-matched peers with TD. After controlling for language and SES, there were no significant associations between ToM and pretend play in children with and without SLI. When language groups were analyzed individually, different patterns of associations emerged for children with and without SLI. ToM was positively associated with pretend play in children with TD but negatively associated in children with SLI. Moreover, inconsistent patterns of associations were observed for some children with SLI (i.e., poor ToM understanding but sophisticated pretend play or vice versa). This study demonstrated that children with SLI may also have concomitant problems in ToM and pretend play, which may have implications for clinical assessment and intervention. The study contributes to the literature by investigating the link between ToM and different forms of sophisticated pretend play in children with and without SLI. Given the different patterns of partial correlations, future investigation of the relationship between ToM and pretend play relationship is warranted.

Previous research into children’s understanding of line of sight has led to differing conclusions as to when and how children become able to appreciate that their view of an object will be different from another persons’ view of the same object. This is probably due to the diversity of response methods required from the children as well as different types of tasks and settings being used between the experiments. The aim of the present thesis is to investigate systematically how children will fare across various settings and whether their comprehension of line of sight can be biased by the task’s setting. The first experiment assessed children’s understanding of line of sight through a tube that was bent to varying degrees of curvature and whether their response pattern would change when feedback was provided. Results showed that children have great difficulty performing correctly on this task, especially when the degree of curvature is small. The older children corrected their response pattern when feedback was provided but the younger children tended to persevere in their response pattern regardless of contradictory feedback. The second experiment looked at children’s performance when walls were used - half the walls were smooth gradual curves while the other half was walls made up of two segments that met to form an angle. Again the children were asked to predict if two dolls placed at opposite ends of each wall would be able to see each other. Results showed that though even young children have no trouble in performing correctly on the “angled” walls, performance on the curved walls was significantly poorer with the older children performing better than the younger children. The third experiment sought to quantify the point at which children deemed line of sight became possible. To do this we used a single “U” shaped trench with the children being asked if one doll could see another in various configurations. The results showed a strong bias towards over estimating visibility. The fourth experiment repeated the second experiment but used wooden trenches instead of walls but also sought to quantify the “switchover” point at which the children deem vision becomes possible between the two dolls. The difference between angles and curves was once again replicated as was the age difference. The fifth experiment compared children’s appreciation of line of sight through/along tubes, trenches and walls. This performance level varied strongly depending on the type of task the child was asked to perform upon with the tube proving to be the most difficult and the angled trench the easiest. The overall findings of the experiment pointed to a context-dependent performance, implying a piece-meal development of childrens’ comprehension of line of sight.

Research on theory of mind (ToM) has been dominated by the traditional False Belief tasks; however, recent work has established a developmental sequence for children’s mental-state understanding. Wellman and Liu (2004) formulated a ToM scale that tests four additional aspects of ToM abilities in the visual realm: Diverse Desires, Diverse Beliefs, Knowledge Access, and Real-Apparent Emotions. Our study extended the scale to include five parallel tasks assessing ToM in the auditory realm. Sixty-six typically developing preschoolers (30 female) between the ages of 3- and 5-years-old were tested using 10 ToM tasks (5 visual, 5 auditory). A 3(age) x 2(modality) x 2(gender) repeated measures ANOVA yielded significant effects for age and gender, where 4- and 5-year-olds demonstrated greater mental-state understanding than 3-year-olds and girls passed more tasks than boys. There was no effect of modality nor did any interactions emerge. Like the visual tasks in the theory-of-mind scale, the auditory tasks form a scalable set, with Diverse Desires and Diverse Beliefs occurring earlier in the scale than Knowledge Access, False Belief, and Real-Apparent Emotions. Our new scale provides researchers with five novel tasks to measure the progression of theory-of-mind development in the auditory realm and may be extended to assess preschoolers, such as children with visual impairments and children with autism spectrum disorder, who have shown delays in mental-state understanding when tested using predominantly visual tasks

Understanding others’ emotions and false beliefs, known as Theory of Mind (ToM), and to recognise and produce facial expressions of emotion has been linked to social competence. Deaf children born to hearing parents have commonly shown a deficit, or at best a delay in ToM. The emotion processing skills of deaf children are less clear. The main aims of this thesis were to clarify the ability of emotion recognition in deaf children, and to provide the first investigation in emotion production. While deaf children were poorer than hearing controls at recognising expressions of emotion in cartoon faces, a similar pattern was found in both groups’ recognition of real human faces of the six basic emotions (happiness, sadness, anger, fear, disgust and surprise). For deaf children, emotion recognition was better in dynamic rather than static, and intense rather than subtle, displays of emotion. With the exception of disgust, no differences in individual emotions were found, suggesting that the use of ecologically valid dynamic real faces facilitates deaf children’s emotion recognition. Deaf children’s ability to produce the six basic emotions was compared to hearing children by videoing voluntary encodings of facial expression elicited via verbal labels and emotion signed stories, and the imitation of dynamic displays of real facial expressions of emotion. With the exception of a poorer performance in imitation and the verbally elicited production of disgust, deaf children were consistently rated by human judges overall as producing more recognisable and intense expressions, suggesting that clarity and expressiveness may be important to deaf individuals’ emotion display rules. In line with previous studies, results showed a delay in passing the first and second order belief tasks in comparison to age matched controls, but not in comparison to a group of ‘age appropriate’ hearing control children. These findings encouragingly suggest that while deaf children of hearing parents show a delay in ToM and understanding disgust, emotion processing skills follow a broadly similar pattern of development to hearing control children. Language experience is implicated in difficulties faced in social and emotion cognition, with reduced opportunities to discuss more complex emotional and mental states.

Thesis advisor: Liane L. Young / Thesis advisor: Elizabeth A. Kensinger / Theory of mind refers to the process of representing others’ mental states. This process consistently elicits activity in a network of brain regions: the theory of mind network (ToMN). Typically, theory of mind has been understood in terms of content, i.e. representing the semantic content of someone’s beliefs. However, recent work has proposed that ToMN activity could be better understood in the context of social prediction; or, more specifically, prediction error—the difference between observed and predicted information. Social predictions can be represented in multiple forms—e.g. dispositional predictions about who a person is, prescriptive norms about what people should do, and descriptive norms about what people frequently do. Part 1 examined the relationship between social prediction error and ToMN activity, finding that the activity in the ToMN was related to both dispositional, and prescriptive predictions. Part 2 examined the semantic content represented by moral claims. Prior work has suggested that morals are generally represented and understood as objective, i.e. akin to facts. Instead, we found that moral claims are represented as far more social than prior work had anticipated, eliciting a great deal of activity across the ToMN. Part 3 examined the relationship between ToMN activity and metaethical status, i.e. the extent that morals were perceived as objective or subjective. Objective moral claims elicited less ToMN activity, whereas subjective moral claimed elicited more. We argue that this relationship is best understood in the context of prediction, where objective moral claims represent strong social priors about what most people will believe. Finally, I expand on this finding and argue that a theoretical approach incorporating social prediction has serious implications for morality, or more specifically, for the motivations underlying normative compliance. People may be compelled to observe moral rules because doing so maintains a predictable social environment. / Thesis (PhD) — Boston College, 2017. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Psychology.

Thesis advisor: Ellen Winner / Despite the widespread involvement of individuals in drama either as performers or audience members, psychologists know very little about the cognitive and affective underpinnings of acting. Acting may provide a powerful lens through which to understand how we understand our own and others' minds. In this dissertation, I review research on theory of mind, empathy, and emotion regulation, show how these three skills are related to acting theory and acting training, and discuss studies I have previously completed demonstrating correlations between skill in acting and skill in theory of mind, empathy, and positive emotion regulation. I then completed four studies. Study 1 was a longitudinal study comparing children (ages 8-10) receiving acting vs. visual arts training over the course of one academic year testing the hypothesis that acting training in childhood is causally related to development of advanced theory of mind, positive emotion regulation, and empathy. Study 1 found that children in acting classes gain in empathy and expression of emotion over a year above children involved in other art forms. Study 2 was a qualitative study designed to determine the kinds of habits of mind taught, explicitly and implicitly, in acting classes for children (ages 8-10). The purpose of Study 2 was to determine the extent to which acting teachers strive to teach theory of mind, empathy, and adaptive emotion regulation in their acting classes. Study 2 found that children in acting classes at this age are taught about physicality and motivation, with no emphasis on empathy or emotion regulation and only a slight emphasis on theory of mind. Study 3 was parallel to Study 1, but with young adolescents, aged 13-15. Study 3 found that adolescents involved in acting classes gain in their empathy, theory of mind acuity, and expressive emotion regulation over the course of a year over and above adolescents involved in other art forms. Study 4 was parallel to Study 2, with acting classes for adolescents. Study 4 found that adolescent acting classes focus on theory of mind and motivation, without any emphasis on empathy or emotion regulation. I conclude by considering the potential impact of this research on our understanding of typical development in theory of mind, empathy, emotion regulation, and on our understanding of individuals deficient in these skills. / Thesis (PhD) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Psychology.