Serotonergic stimulation in relation to approach-avoidance behavior in patients with anxiety disorders and borderline personality disorder

Patients with borderline personality disorder (BPD) and with anxiety disorders (AD) clearly contrast in personality traits (predominantly impulsivity and anxiety), behavior (avoidance vs. impulsive (approach) behavior) and neurobiological reactivity upon serotonergic stimulation. According to Gray (1973) impulsivity and anxiety are independent personality traits which are characterized by a different susceptibility for stimuli of reward and punishment. Furthermore, these two dimensions of personality differ in serotonergic reactivity. Therefore, a study in patients with BPD and AD, which includes the assessment of personality, behavior and neuroendocrinology has been conducted. So far, 15 patients with BPD and 11 patients with AD could be examined. All patients had to complete personality questionnaires, such as I7, BIS 11 (impulsivity), STAI, related traits of NEO FFI (anxiety). In addition, all patients underwent an approach-avoidance paradigm in which reward and punishment were systematically varied. Furthermore, a serotonergic stimulation test (citalopram 20mg) with the assessment of cortisol and prolactin was performed in the afternoon in both groups. The preliminary results of this study show that cortisol stimulation by citalopram differs between groups, showing a more pronounced cortisol rise in BPD than in AD after citalopram. Differences in the behavioural approach-avoidance paradigm in relation to the serotonergic stimulation will be presented and discussed.