RESUMO
BACKGROUND: Previous eye-tracking studies provide preliminary evidence for a hypersensitivity to negative, potentially threatening interpersonal cues in borderline personality disorder (BPD). From an etiological point of view, such interpersonal threat hypersensitivity might be explained by a biological vulnerability along with a history of early life adversities. The objective of the current study was to investigate interpersonal threat hypersensitivity and its association with adverse childhood experiences (ACE) in patients with BPD employing eye-tracking technology. METHODS: We examined a sample of 46 unmedicated, adult female patients with BPD and 25 healthy female volunteers, matched on age and intelligence, with a well-established emotion classification paradigm with angry, fearful, happy, and neutral facial expressions. ACE were assessed retrospectively with the Childhood Trauma Questionnaire. RESULTS: Patients as compared to healthy volunteers reflexively directed their gaze more quickly towards the eyes of emotional and neutral faces and did not adapt their fixation patterns according to the facial expression presented. Misclassifying emotional and neutral faces as angry correlated positively with the patients' self-reported ACE. CONCLUSIONS: Building on and extending earlier findings, our results are likely to suggest a visual hypervigilance towards the eyes of emotional and neutral facial expressions and a childhood trauma-related anger bias in patients with BPD. Given the lack of a clinical control group, the question whether these findings are specific for BPD has to remain open. Thus, further research is needed to elucidate the specificity of altered visual attention allocation and the role of ACE in anger recognition in patients with BPD.
RESUMO
The neuropeptide oxytocin (OT) has been shown to play a modulatory role in nociception. However, analgesic effects of OT in chronic pain conditions remain elusive and the neural underpinnings have not yet been investigated in humans. Here, we conducted an exploratory, randomized, placebo-controlled, cross-over study to examine effects of intranasal OT in male patients suffering from chronic low back pain (CBP) versus healthy controls (HC). N = 22 participants with CBP and 22 HCs were scanned using functional magnetic resonance imaging (fMRI) while they continuously rated either spontaneously occurring back pain or acute thermal pain stimuli applied to the lower back. During heat pain processing we found that OT versus PL attenuated pain intensity ratings and increased BOLD responses in the caudate nucleus of the striatum in CBP versus HCs. Spontaneously experienced pain in contrast to heat pain was associated with activation changes in the medial frontal cortex (MFC) and the anterior cingulate cortex (ACC) as reported in previous studies. However, we did not observe OT effects on spontaneously experienced pain in CBP patients. Overall, our preliminary data may suggest that the striatum is a key structure underlying the pain-modulating effects of OT in patients with chronic pain and adds to the growing evidence linking the neuropeptide to pain modulation in humans. Further studies on neuronal OT effects in larger samples of chronic back pain patients are needed to understand probable mechanisms of OT effects in chronic pain. This article is part of the special issue on Neuropeptides.