Dissertation Defenses

Doctoral Dissertation Announcement

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Candidate: Dayanthi Nishani Samaraweera

Degree of: Doctor of Philosophy

Department: Psychology

Title: The Effects of Brief Visual Stimuli on the Anxious Arousal Associated with Public Speaking

Committee:
Dr. C. Richard Spates, Chair
Dr. Scott Gaynor
Dr. Lisa Baker
Dr. Ellen Koch

Date: Wednesday, May 26, 2010 3:00 p.m. - 5:00 p.m.
3715 Wood Hall

Abstract:
Public speaking anxiety as a form of social phobia has been the topic of numerous research investigations (Anderson, Rothbaum, & Hodges, 2003; Anderson, Zimand, Hodges, & Rothbaurn, 2005; Foley & Spates, 1996; Harris, Kemmerling, & North, 2002; Klinger et al., 2005; Waller, 2004). Exposure based treatments are the standard form of therapy for public speaking anxiety and have been implemented in massed form and in repeated intervals of relatively shorter duration. This study manipulated the duration of exposure to the feared situation by presenting visual images subjected to the technique of backward masking. This study examined whether a period of exposure so short as to be virtually unreportable, could bring about a reduction in anxious arousal and self reported levels of anxiety in the course of a single exposure session, minus the training in anxiety management. Participants in the study were assigned into five conditions – the backwardly masked images condition-I, the backwardly masked images condition-1 (control for backwardly masked images condition-2), the easily reportable images condition, the target images only condition and the masking images only (control) condition to examine this proposition. Pre and post-exposure anxiety were assessed via facial electromyogram (fEMG) at the corrugator supercilii muscle and self report measures. Self-report measures consisted of the Profile of Mood States questionnaire and ratings of subjective units of distress. Within session changes in anxiety were assessed via fEMG. Contrary to expectation, it was found that individuals in the backwardly masked images condition did not display a greater reduction in anxiety as compared to individuals in the other three conditions. Instead, when images were displayed for a slightly longer duration, allowing individuals to clearly see both the target and the mask, a greater reduction in anxiety was observed.