Degree Name

Doctor of Philosophy


School of Education


This thesis explores the nature of engagement in asynchronous discussion forums in fully delivered online courses in higher education; in particular, online engagement as part of the total subject design. It addresses a number of research questions to understand how online discussion forums shape the teaching-and-learning experience, namely: What kinds of knowledge are socially constructed in online forum interactions? What is the role of interpersonal contributions in fostering/inhibiting student engagement in forum interaction, and in building a sense of community? What is the role of the instructor in mediating online discussion?

The study was motivated to understand how interaction - essential for reducing isolation, constructing knowledge and building community - was affected by the disruption to interactivity caused by lack of physical presence, hence of immediacy for clarification; lack of meaning-making cues (gesture, voice variation etc); and the incongruence of written discussion, i.e. interacting in a written format. It is concerned with pedagogical implications for online participants, as achieving effective interaction can be elusive in online discussion forums.

The study investigated three postgraduate online TESOL classes at an Australian regional university. It adopts a qualitative multiple case study design to examine the discussions as they unfolded in an authentic online classroom environment over one academic semester. Data comprises discussion forum texts, supplemented by interviews (with academic subject designers, instructors and students) and surveys of student perceptions (on learning and community), as well as pedagogic artifacts from the learning sites (topic guides, discussion tasks, learning resources etc).

The research reported takes a socio-semiotic approach; that is, it draws on the complementarity of sociocultural theory (Vygotsky, 1978) and social semiotics (Halliday 1978; 1985). The combination of Sociocultural and Systemic Functional Linguistics (SFL) theories provides a robust framework to analyse the complexities of language use in the online teaching-learning context, enabling focus to move from the macro-level of context, to the micro-level of specific instances of text. The interpersonal dimensions of forum interactions were examined using Appraisal – the system offered within SFL theory to account for linguistic expressions of affect, opinion and evaluation. Similarly, the joint construction of knowledge, ideas via forum dialogue, are described using Transitivity and Logicosemantics – systems which describe the nature of ideas being exchanged and the relations between them.

The analysis reveals that identity formation is an important but under-explored area in online learning concluding that social dis/alignments and perceptions of (positive/negative) identity caused learners to become more or less engaged in interaction. It suggests that ‘identity trajectory’ is a way of understanding the opportunities for engagement that are taken up or constrained by one’s perceptions of identity, constructed in socially negotiated relationships. The study demonstrates the crucial role of instructor mediation in shaping dialogic opportunities that move learners towards new understandings. Close attention to the unfolding language choices of the participants provides fresh insights into the complex relationships between the intersubjective and experiential in adult learning environments. Finally the study proposes three online talk types – non-dialogic online talk, online cumulative talk and online exploratory talk. This highlights the notion of attending to (the online equivalent of face-to-face ‘listening and responding’) as a precursor to effective online interaction which opens dialogic space for co-construction of knowledge.

The thesis provides detailed analyses and commentary on how online discussion forums shaped the teaching-learning experience of the participants. The significance of the study is its contribution to online pedagogy and online design, which takes into account the agency of adult learners, the role of the instructor, and the development of mutual understanding and interpersonal connectedness. Importantly, it highlights that assumptions cannot be made of the online communicative expertise of learners (nor instructors) for engaging in pedagogically-effective asynchronous dialogue.