The overarching goal of this thesis was to examine aspects of childhood amnesia in children, adolescents, and adults, and to evaluate theoretical explanations for the phenomenon. The research addressed three main questions. First, at what age does the boundary of childhood amnesia occur in adults, and what is the shape of the boundary? Second, is it possible for children to verbally express preverbal aspects of their memories after a 6-year delay? Third, is maternal narrative style during early childhood related to the age of adolescents� earliest autobiographical memories? In Experiment 1A, I examined whether the way in which we ask adults to sample their memories alters estimates of the offset of childhood amnesia. Independent groups of adults were asked to describe and date one memory from any time in their lives associated with each of six cue words (Lifespan Condition), one childhood memory associated with each of six cue words (Childhood Condition), or their earliest memory associated with each of six cue words (Cued Earliest Condition). A fourth group of adults was asked to describe and date their six earliest memories (Uncued Earliest Condition). As predicted, participants in the Cued Earliest and Uncued Earliest Conditions reported earlier memories than participants in the Childhood Condition, who in turn reported earlier memories than participants in the Lifespan Condition. Consistent with prior research, when adults were asked to report their earliest memories, with or without the use of cue words, the mean age of the earliest memory reported was between 3 and 4 years. In Experiment 1B, I examined the distribution of the early memories reported by six individual adults by asking them to report all the memories that they could recall from each year of childhood, until they had reported at least their 20 earliest memories. When the number of memories recalled was plotted as a function of age at event, the distributions looked like step functions, with the step occurring at ages 4-6 years. Participants also reported some early memories for events that occurred before this age. In Experiment 2, I examined children�s and parents� verbal and non-verbal recall for a specific event - the Magic Shrinking Machine - after a 6-year delay. The children were aged 27-51 months when they originally played with the machine. After a 6-year delay, nine of 46 children and 26 of 42 parents verbally recalled the event. There were no age-related differences in the amount or accuracy of the information that participants reported about the event. When children�s reports were compared to their task-relevant vocabulary measured at the time of the event, there were just two instances in which a child used a word to describe the event that had not been part of his or her productive vocabulary at the time of the event. Children showed no non-verbal recall of the event, relative to a group of age-matched controls. In Experiment 3, I tested the hypothesis that the way that parents talk about the past with their children during early childhood will influence the age of these children�s earliest autobiographical memories when they are older. Conversations about past events between 17 mother-child dyads were recorded on multiple occasions between the children�s 2nd and 4th birthdays. When these children were between the ages of 12-13 years, they were asked to describe their earliest autobiographical memory. Adolescents whose mothers used a greater ratio of elaborations to repetitions when discussing the past with their child during early childhood had earlier first memories than did adolescents whose mothers used a smaller ratio of elaborations to repetitions. The present findings on adults� earliest memories are consistent with a two-stage model of childhood amnesia. Theories that draw on multiple cognitive developments provide a more complete account of childhood amnesia than theories that focus on a single developmental milestone. I propose that neurological maturation and language acquisition set the stage for subsequent language-related developments that contribute to the emergence of autobiographical memory and, ultimately, the offset of childhood amnesia.

Theory of mind has been described in philosophical and psychological literature as "folk psychology", and is the tacit understanding that our behaviour is driven by our thoughts, desires and beliefs (Wellman, Cross, & Watson, 2001). Children are widely considered to have attained theory of mind understanding when they are able to pass the test of false belief understanding devised by Wimmer and Perner (1983), at around 4 years of age. There are many theories as to how a child comes to hold a folk psychology, including innate modularism (Leslie, 1987, 1988, 1994), theory change (Gopnik & Wellman 1992), developing representational understanding (Perner, 1991, 1995, 2000), and experiential understanding developed in a socio-linguisitic context (Nelson, 1996). In addition, theory of mind has been linked to the development of symbolic understanding (Deloache & Smith, 1999; Perner, 1991), pretend play (Leslie, 1987; Taylor & Carlson, 1997; Youngblade & Dunn, 1993), language (Astington & Jenkins, 1999; Nelson, 1996; Olson, 1988) and executive function (e.g. Hughes, 1998a; Kochanska et al., 1996; Reed et al., 1984). The present study sought to bring together these diverse findings and to attempt to provide an integrated account of the emergence of theory of mind understanding during the preschool years. Sixty-four New Zealand children were assessed on their mental state understanding, deceptive abilities, symbolic functioning, language, and executive skills, when they were aged 30, 36, 42 and 48 months of age. There were a number of key findings in the present study. Language was a powerful predictor of false belief performance both within and across time, and was also related to many of the other variables included in the study. Performance on the scale model test of symbolic functioning was related across time to children�s concurrent and later false belief understanding. Scale model performance was also intertwined in a bidirectional relationship with language, and language appeared to play an increasingly important role in mediating the relationship with false belief understanding across time. False belief understanding and scale model performance were also related within and across time to executive function. There was evidence to suggest that the importance of working memory was due to its role in conflict inhibition. Although deception has sometimes been posited to be a precocious manifestation of theory of mind (Chandler, Fritz, & Hala, 1989), in the present study deceptive ability lagged false belief understanding. Furthermore, false belief understanding was related to children�s subsequent (but not earlier) responses to a protagonist�s intention. This supports the hypothesis that false belief understanding allows a qualitative change in the execution of deception, whereby children can move from simple physical strategies to more sophisticated mentalist strategies. Overall, the present study provides some evidence to suggest that symbolic functioning, language, and later theory of mind may form part of a single developing skill set of symbolic representation. In dynamic interaction with social understanding, and supported by cognitive abilities such as executive function, and the socio-linguistic context, it is argued that understanding of one�s own and other minds emerges. Children�s ability to solve the false belief problem at 4 years of age is presented as a milestone on a developmental continuum of social understanding.

Thesis (PhD) -- University of South Australia, 1999

Thesis (Ed. D.)--Trinity Evangelical Divinity School, 1988. / Includes bibliographical references (leaves 211-218).

Thesis (Ph. D.)--University of Toronto, 2004. / Adviser: Janet W. Astington.

Thesis (B.A. (Hons.)), Department of Psychology, University of Adelaide, 1973.

Thesis (M.Ed. 1978) from the Department of Education, University of Adelaide.

Thesis (M.Ed.)--University of Melbourne, Faculty of Education, 2000. / Typescript (photocopy). Includes bibliographical references (leaves 163-166).

Thesis (Ph.D)--University of Adelaide, Dept. of Pure Mathematics, 2001. / Includes bibliographies and index. Also available in an electronic version via ADT (Australian Digital Theses) Program.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 74-84). Also available via the Internet.