Moniek Hutschemaekers

25 Neuroendocrinological aspects of social anxiety and aggression related disorders Introduction Steroid hormones, like cortisol and testosterone, play an important role in the regulation of social motivational behavior. Whereas testosterone facilitates threat approach, presumably by facilitating dopaminergic projection from the amygdala to the striatum (de Souza Silva, Buddenberg, Huston, Topic, & Mattern, 2008; Hermans et al., 2010; Radke et al., 2015), cortisol increases threat avoidance, particularly in high socially anxious individuals (van Peer et al., 2007; van Peer, Spinhoven, Dijk, & Roelofs, 2009). Interestingly, social motivational disorders, such as social anxiety, and aggression-related disorders show an imbalance in these steroid hormones: social anxiety has been associated with increased cortisol stress-responses and decreased testosterone levels (Gerra et al., 2000; Giltay et al., 2012; Roelofs, Minelli, Mars, van Peer, & Toni, 2009), while aggressive psychopathologies have been linked to increased testosterone levels (Glenn, Raine, Schug, Gao, & Granger, 2012; Montoya, Terburg, Bos, & van Honk, 2012; Volman et al., 2016). In this chapter, we discuss the role of these steroid hormones and the neuropeptide oxytocin in social psychopathologies, especially social anxiety and psychopathy. First, we will give a description of the neuroendocrine aspects of social motivational behavior, including social approach and avoidance behaviors. Then we will focus on the neuroendocrine aspects of social anxiety and aggression-related disorders. Finally, motivational and psychiatric findings will be integrated, followed by a research agenda, aiming to provide starting points for clinical applications. Social motivational action The term motivation reflects a broad concept related to anything that may prompt the person to act in a certain way, or to develop an inclination for specific behavior. In this chapter though, we will focus largely on social motivational actions that can be roughly divided into social approach and social avoidance (Davidson, Ekman, Saron, Senulis, & Friesen, 1990; Gray, 1994). These action tendencies involve a basic response to stimulus valence. They are mediated by primary motivational systems of the brain -whereby reward potentiates behavioral activation, while punishment promotes behavioral inhibition or avoidance - and are thought to underlie every complex emotional responding (Carver & White, 1994; Gray & MacNaughton, 2003). Successful social functioning depends on adaptive regulation of these social approach and avoidance responses. Both automatic defensive action tendencies and more instrumental (or goal-directed) mechanisms shape an individual’s behavior. When an individual encounters a social 2

RkJQdWJsaXNoZXIy MTk4NDMw