Psychophysiological adaptivity and the formation of paranoid delusions.

由于偏执症状引起的相当多的负面后果和迄今为止的治疗益处不足，更好地了解妄想的形成是必要的。与易受压力模型一致，迄今为止的研究指出了失调的压力反应，例如增加的负面影响，增加的自主觉醒和异常的皮质醇反应。然而，目前还不清楚适应不良的压力反应到底是如何导致症状的。为了回答这个问题，神经内脏整合模型（Thayer & Lane，2000）提供了一个重要的基础。在该模型中，迷走神经心率变异性（HRV）是生物体灵活适应的指标。此外，HRV被概念化为皮质-外周反馈回路的有效性的指标，从而与下丘脑-垂体-肾上腺轴的功能和情绪调节能力相关联。在健康个体中，研究表明HRV降低预示着生理适应性降低，这在压力源后恢复减少中尤其明显。对于患有精神障碍的参与者，几项研究表明，与健康对照组相比，HRV大幅降低。基于此，本研究将探讨偏执妄想患者的低心率变异性与心理生理适应性之间的关系。预期由于与降低的HRV相关的情绪调节缺陷，在应激源受损后重建稳态并且维持对威胁的感知。（过去或现在）n=50），将其与健康对照（n=50）进行比较，我们计划调查（1）偏执妄想症患者的适应性改变是否明显表现为从压力源中恢复的减少;（2）较低的恢复效率是否与对新的应激源的反应性增加有关;以及（3）哪些机制可以分别解释功能失调的恢复和应激敏感性，这些机制（即，降低的基线HRV的预测性、情绪调节的中介和调节作用、增加的负面情绪）与偏执狂的增加相关。为了验证这些假设，计划的项目包括两个应激阶段（双侧足冷加压任务加起搏串行添加任务），每个阶段都有一个恢复期。第一个恢复期将持续60分钟，以使唾液皮质醇恢复至基线水平。沿着对妄想形成机制的理解，该项目将有助于更好地理解HRV降低如何预测心理生理适应性和症状形成。基于这一知识，有针对性的有效治疗干预措施（例如，生物反馈，情绪调节集中治疗）。

Due to considerable negative consequences caused by paranoid symptoms and the as of yet insufficient therapeutic benefits, a better understanding of the formation of delusions is necessary. In line with vulnerability-stress-models, research available to date points towards a dysregulated stress reaction, such as an increased negative affect, increased autonomic arousal and an aberrant cortisol response. It is not yet clear, however, how exactly a maladaptive stress reaction leads to symptoms. To answer this question, the neurovisceral integration model (Thayer & Lane, 2000) provides an important basis. In this model, vagal heart rate variability (HRV) is an indicator of a flexible adaptation of the organism. Moreover, HRV is conceptualized as an index of the effectivity of cortical-peripheral feedback loops, thereby linked to the functioning of the hypothalamic-pituitary-adrenal axis and emotion regulation abilities. In healthy individuals, research showed diminished HRV to be predictive of a reduced physiological adaptivity, which was particularly evident in a reduced recovery after a stressor. For participants with psychotic disorders, several studies have shown a substantially reduced HRV when compared to healthy controls. Based on this, the present project will investigate the association between low HRV and the psychophysiological adaptivity in participants with paranoid delusions. It is expected that due to the emotion regulation deficits related to a reduced HRV, reestablishment of homeostasis after a stressor is impaired and perceptions of threat are maintained.In a sample of participants with paranoid delusions (current or past; n=50) who will be compared to healthy controls (n=50), we plan to investigate (1) whether an altered adaptivity in participants with paranoid delusions is evident in a reduced recovery from a stressor; (2) whether less efficient recovery is associated with an increased reactivity to a new stressor; and (3) which mechanisms may explain the dysfunctional recovery and stress sensitivity, respectively whether these mechanisms (i.e., predictivity of a diminished baseline HRV, mediating and moderating role of emotion regulation, increased negative affect) are associated with an increase in paranoia. To test these assumptions, the planned project involves two stressor phases (bilateral feet-cold-pressor task plus paced serial addition task), each followed by a recovery period. The first recovery period will last 60 minutes to allow for salivary cortisol recovery to baseline. Along with enhancing the understanding of mechanisms to delusion formation, the project shall contribute to a better understanding of how reduced HRV may predict psychophysiological adaptivity and symptom formation. Based on this knowledge, targeted effective therapeutic interventions (e.g., biofeedback, emotion regulation focused therapy) could be inferred.