Derome Mélodie, Conring Frauke, Gangl Nicole, Hatzipanayioti Adamantini, Wüthrich Florian, Rüter Maximilian, Lefebvre Stephanie, Walther Sebastian, Stegmayer Katharina
Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland.
Graduate School for Health Sciences, University of Bern, Bern, Switzerland.
Schizophrenia (Heidelb). 2025 May 21;11(1):77. doi: 10.1038/s41537-025-00625-x.
Increased personal space (PS) is a clinically relevant marker for paranoia. Neuroimaging evidence suggested limbic and prefrontal circuit alterations related to threat processing and emotion regulation (i.e., amygdala, fronto-parietal cortex). We hypothesize that patients with paranoia will respond with altered activation in PS-relevant brain areas (i.e., limbic regions, fronto-parietal cortex) toward personal space intrusion. We included 79 participants with various degrees of paranoia severity; 49 patients diagnosed with schizophrenia and 30 controls. In this fMRI study, participants passively viewed pictures of facial expressions in approaching, static, or retracting motions. Violation of PS was modelled with the approaching faces condition. We used firstly a cut off to separate patients in high and low paranoia, and secondly the continuous variations of paranoia severity to understand the full picture. While participants were passively watching faces approaching them in contrast to static faces, group comparison revealed that patients with high paranoia showed hypoactivity mainly in the OFC when compared to patients with low paranoia, and hypoactivity in dlPFC and dPCC when compared to controls. Further, paranoia severity was positively associated with activation of the right hippocampus. Altered neural activity in the OFC, dlPFC, and hippocampus may well reflect the neural responses to the paranoid experience of threat and provide evidence for the hypothesized association between limbic dysfunction and paranoid threat. Modelling of paranoia severity captures variance in neural response to approaching threat, which may be previously undetected due to heterogeneity when examined at the group level.
个人空间（PS）增加是偏执狂的一个临床相关指标。神经影像学证据表明，边缘系统和前额叶回路的改变与威胁处理和情绪调节有关（即杏仁核、额顶叶皮质）。我们假设，偏执狂患者在个人空间受到侵犯时，与个人空间相关的脑区（即边缘区域、额顶叶皮质）的激活会发生改变。我们纳入了79名具有不同程度偏执严重程度的参与者；49名被诊断为精神分裂症的患者和30名对照组。在这项功能磁共振成像研究中，参与者被动观看面部表情处于接近、静止或退缩动作的图片。用接近面部的条件来模拟个人空间的侵犯。我们首先使用一个临界值将患者分为偏执程度高和低两组，其次使用偏执严重程度的连续变化来全面了解情况。当参与者被动观看接近他们的面部与静止面部的对比时，组间比较显示，与偏执程度低的患者相比，偏执程度高的患者主要在眶额皮质表现为活动减退，与对照组相比，在背外侧前额叶皮质和背侧扣带回皮质表现为活动减退。此外，偏执严重程度与右侧海马体激活呈正相关。眶额皮质、背外侧前额叶皮质和海马体中神经活动的改变很可能反映了对偏执性威胁体验的神经反应，并为边缘系统功能障碍与偏执性威胁之间的假设关联提供了证据。偏执严重程度的建模捕捉了对接近威胁的神经反应中的差异，这在组水平检查时可能由于异质性而以前未被发现。
