Oxytocin Normalizes Approach-Avoidance Behavior in Women With Borderline Personality Disorder

Abstract

Background: Interpersonal deficits are a core symptom of borderline personality disorder (BPD), which could be related to increased social threat sensitivity and a tendency to approach rather than avoid interpersonal threats. The neuropeptide oxytocin has been shown to reduce threat sensitivity in patients with BPD and to modify approach-avoidance behavior in healthy volunteers. Methods: In a randomized, double-blind placebo-controlled between-subject design, 53 unmedicated women with BPD and 61 healthy women participated in an approach-avoidance task 75 min after intranasal substance administration (24 IU of oxytocin or placebo). The task assesses automatic approach-avoidance tendencies in reaction to facial expressions of happiness and anger. Results: While healthy participants responded faster to happy than angry faces, the opposite response pattern, that is, faster reactions to angry than happy faces, was found in patients with BPD. In the oxytocin condition, the "congruency effect" (i.e., faster avoidance of facial anger and approach of facial happiness vice versa) was increased in both groups. Notably, patients with BPD exhibited a congruency effect toward angry faces in the oxytocin but not in the placebo condition. Conclusions: This is the second report of deficient fast, automatic avoidance responses in terms of approach behavior toward interpersonal threat cues in patients with BPD. Intranasally administered oxytocin was found to strengthen avoidance behavior to social threat cues and, thus, to normalize fast action tendencies in BPD. Together with the previously reported oxytocinergic reduction of social threat hypersensitivity, these results suggest beneficial effects of oxytocin on interpersonal dysfunctioning in BPD.

Keywords: angry; congruency effect; happy; placebo; reaction time.

Figure 1

Reaction times in ms (mean ± standard error) during performance of the approach–avoidance task. (A) Significant group-by-emotion-by-congruency interaction with missing congruency effect for angry faces in patients with borderline personality disorder (BPD). (B) Significant substance by congruency interaction with longer reaction times after application of oxytocin than placebo in the incongruent condition over all participants. Factor “IQ” and estradiol and progesterone levels included as covariates. Significant comparisons are marked with an asterisk indicating p < 0.05 at the post-hoc test. OXT, oxytocin; PLA, placebo.

Figure 2

Presentation of congruency effect after application of oxytocin in patients with borderline personality disorder (BPD). Difference scores (incongruent–congruent conditions) of reaction times in ms (mean ± standard error). Factor “IQ” and estradiol and progesterone levels included as covariates. Significant comparisons are marked with an asterisk indicating p < 0.05. OXT, oxytocin; PLA, placebo.