The overarching goal of this thesis was to explore the extent to which the developmental trajectory and timetable of children’s theory of mind (ToM) growth is shaped by aspects of the family environment namely, maltreatment (Study 1), non-abusive parent disciplinary strategies (Study 2) and Indigenous culture and language (Study 3). In observing the development of ToM understanding in the home, the fourth study of this thesis sought to examine the links between children’s ToM acquisition and their application of this knowledge in peer interactions in the classroom. The four studies contained in this thesis document the development of the spectrum of ToM concepts, ranging from first-order false belief through to more advanced, higher-order ToM understanding. Moreover, by using Wellman and Liu’s (2004) reliably scalable five-step ToM Scale as well as the inclusion of Peterson, Wellman and Slaughter’s (2012) sixth-step of the ToM Scale in Study 4, compelling insights into the developmental timetable and developmental progression of children’s ToM mastery were revealed. Study 1 (N = 105) examined both first-order false belief and advanced ToM understanding in a sample of maltreated and non-maltreated primary school-aged children. Results indicated that ToM understanding developed at a slower pace in maltreated children with significant delays observed in both advanced false-belief and belief-emotion understanding. However, interestingly, other ToM abilities such as emotion concealment were not adversely affected by the experience of maltreatment.
In light of these intriguing findings, Study 2 (N = 60) explored the influence of non-abusive types of parenting practices, in particular, authoritarian and authoritative parenting attitudes in relation to children’s mentalizing abilities. Results indicated that authoritarian attitudes of control and conformity were linked to poor ToM understanding whereas authoritative attitudes endorsing openness and child autonomy was found to facilitate and promote children’s ToM growth. Given, these interesting findings, Study 3 (N = 97) was a cross-cultural examination of ToM understanding in Indigenous-Australian toddlers and children who spoke Aboriginal English as their first language. In contrast to prior research, findings revealed that although Indigenous-Australian children demonstrated clear linguistic delays, this did not impede their ToM growth. In fact, results indicated a faster developmental progression and pace of ToM mastery in Indigenous children with the precocious 2-year-old Indigenous toddlers demonstrating an advanced understanding of the early-developing ToM concepts compared to the non-indigenous children who were linguistically adept. The results of this pioneering study suggest the strong sense of kinship, belonging and connectedness central to Indigenous culture is conducive to the fast-paced development of the early-emerging ToM concepts.
Lastly, in observing the development of ToM understanding within the context of the family, it was important to examine how children’s ToM growth manifests in everyday social interactions outside of the family home. With prior research highlighting important links between mindreading skills and friendship (Slaughter, Dennis, & Pritchard, 2002), the fourth and final study (N = 60) of this thesis sought to uncover a direct link between typically-developing children’s acquisition of ToM understanding and the application of this ToM knowledge in their peer interactions at school. Using teacher ratings on Peterson, Slaughter and Paynter’s (2007) psychometrically sound Peer Social Maturity Scale (PSMAT), evidence of a direct link was observed as children who performed better on the lab-based measures of ToM understanding were rated as more socially mature compared to children who performed poorly on the ToM tasks. The findings of each study are explored in more detail with reference to the previous literature along with a discussion of both the conceptual and theoretical implications of these nascent findings and suggestions for future research.