20 Chapter 1 ance alleviating, and prosocial properties of testosterone, testosterone might have the potential to enhance exposure treatment efficacy for SAD. Therefore, the overarching aim of this dissertation is to examine whether endogenous or exogenous testosterone increases can enhance exposure efficacy for SAD. Specifically, the first aim is to review the current scientific knowledge on social motivational properties of the HPG-axis and its potential role in social motivational deficiencies underlying affective disorders, such as SAD. Second, we aim to test 1) whether endogenous testosterone is predictive of exposure outcomes, 2) if administrating testosterone to individuals with SAD prior to exposure can improve exposure efficacy and 3), whether automatic avoidance behavior toward social stimuli may moderate the effects of exposure enhancement with testosterone. Outline of this dissertation Chapter 2 presents a theoretical overview of steroid hormones testosterone and cortisol and their relationship with social motivational behavior and psychopathology such as aggression related disorders and SAD in specific. Chapter 3 describes a proof-ofconcept study in which we translated the social challenge hypothesis of testosterone into the clinical practice. In a sample of 73 participants with SAD, this study sought to test whether endogenous pre-treatment testosterone increases, enhances efficacy of a standardized exposure therapy session for SAD, as measured by fear levels during exposure and change in social anxiety symptoms following one standardized exposure session. In chapter 4 the results of a placebo controlled randomized proof-of-concept trial are presented. Concretely, we tested the augmentative potential of administrating one dose of testosterone (0.5 mg sublingual, vs placebo) prior to a speech exposure session for females with SAD (N = 55). Within session fear and social anxiety symptoms were the primary and secondary outcome measures, respectively. In chapter 5 we tested the hypothesis that highly avoidant participants benefit more from the testosterone-enhanced therapy described in chapter 4. We measured pre-treatment automatic avoidance tendencies toward social stimuli with an approach-avoidance joystick task in the same sample as the study described in chapter 4 and tested if these tendencies moderate the effects of testosterone enhanced exposure. Additionally, we tested whether these avoidance tendencies are relatively stable or whether they vary with (testosterone enhanced) exposure efficacy. Finally, I will close with a discussion in chapter 6, presenting an overview and discussion of all findings in light of the existing literature, followed by an evaluation of strengths, limitations and implications for the clinical practice, as well as considerations for future research and concluding remarks.
RkJQdWJsaXNoZXIy MTk4NDMw