Degree Name

Doctor of Philosophy


School of Psychology, Faculty of Social Sciences


Background: Significant change events are defined moments within psychotherapy that provide rich data on effective processes. The therapist-patient conversation reveals complex emotional-cognitive linguistic features of these processes. This thesis aimed to investigate how these variables contribute to psychotherapeutic outcomes. Method: Three sequential studies were undertaken investigating patients with complex mental health disorders, primarily utilising the Therapeutic Cycles Model (Mergenthaler, 1996) method. Study 1 explored the correspondence between therapist-patient emotionalcognitive dialogue and the patient’s dynamic structural change in focal problems across four months of a single case. Study 2 investigated the sequence of therapist-patient linguistic processes in early sessions (N=20) in relation to long-term treatment outcome. Study 3 further examined the emotional-cognitive characteristics of the change events identified in Study 2 using observer-ratings and computerised analysis. Results: Change events were identified and emotional-cognitive process analyses yielded new discoveries about structural dynamic change (Study 1). Emotional-cognitive change events in the third session of therapy predicted 12-month clinical outcomes (Study 2). Therapist-patient dyads most improved spent significantly more time early in session in change events, whilst least improved moved into change events late in session (Study 2). Within change events, there were more positive and negative emotion words, more cognitive insight words, greater awareness and insight into thoughts and feelings, and instances of strengthening of the therapist-patient alliance (Study 3). Conclusion: The therapeutic dialogue is a powerful vehicle connected to dynamic change, with both patient and therapist playing important roles. Together the results underscore the importance of the interaction between emotional engagement and cognitive insight that promote successful outcomes in psychotherapy.