Labrenz Franziska, Knuf-Rtveliashvili Sopiko, Elsenbruch Sigrid
Institute of Medical Psychology & Behavioral Immunobiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
Front Psychiatry. 2020 Mar 24;11:197. doi: 10.3389/fpsyt.2020.00197. eCollection 2020.
Although the broad role of fear and hypervigilance in conditions of the gut-brain axis like irritable bowel syndrome is supported by converging evidence, the underlying mechanisms remain incompletely understood. Even in healthy individuals, it remains unclear how pain-related fear may contribute to pain-related attentional biases for acute visceral pain. Building on our classical fear conditioning work in a clinically relevant model of visceral pain, we herein elucidated pain-related attentional biases shaped by associative learning in healthy women and men, aiming to elucidate possible sex differences and the role of psychological traits. To this end, we compared the impact of differentially conditioned pain-predictive cues on attentional biases in healthy women and men. Sixty-four volunteers accomplished a visual dot-probe task and subsequently underwent pain-related fear conditioning where one visual cue (CS) was contingently paired with a painful rectal distention (US) while another cue remained unpaired (CS). During the following test phase, the dot-probe task was repeated to investigate changes in attentional biases in response to differentially valenced cues. While pain-related learning was comparable between groups, men revealed more pronounced attentional engagement with the CS and CS whereas women demonstrated stronger difficulties to disengage from the CS when presented with a neutral cue. However, when both CS and CS were presented together, women revealed stronger difficulties to disengage from the CS. Regression analyses revealed an interaction of sex, with negative affect predicting stronger avoidance of the CS and stronger difficulties to disengage attention from the CS in men. These results provide first evidence that pain-related fear conditioning may induce attentional biases differentially in healthy women and men. Hence, sex differences may play a role in attentional mechanisms underlying hypervigilance, and may be modulated by psychological vulnerability factors relevant to chronic visceral pain.
尽管越来越多的证据支持恐惧和过度警觉在肠-脑轴相关病症（如肠易激综合征）中所起的广泛作用，但其潜在机制仍未完全明确。即便在健康个体中，与疼痛相关的恐惧如何导致对急性内脏痛的疼痛相关注意偏向也尚不清楚。基于我们在内脏痛临床相关模型中的经典恐惧条件反射研究，我们在此阐明了健康男女中由联想学习塑造的疼痛相关注意偏向，旨在揭示可能存在的性别差异以及心理特质的作用。为此，我们比较了不同条件下的疼痛预测线索对健康男女注意偏向的影响。64名志愿者完成了一项视觉点探测任务，随后接受与疼痛相关的恐惧条件反射训练，其中一个视觉线索（条件刺激，CS）与直肠扩张疼痛（非条件刺激，US）偶然配对，而另一个线索未配对（CS）。在随后的测试阶段，重复进行点探测任务，以研究对不同效价线索的注意偏向变化。虽然两组之间与疼痛相关的学习情况相当，但男性对CS和CS表现出更明显的注意投入，而女性在面对中性线索时，更难从CS上转移注意力。然而，当CS和CS同时呈现时，女性更难从CS上转移注意力。回归分析显示存在性别交互作用，消极情绪预示着男性对CS有更强的回避倾向，且更难将注意力从CS上转移开。这些结果首次证明，与疼痛相关的恐惧条件反射可能在健康男女中引发不同的注意偏向。因此，性别差异可能在过度警觉的注意机制中起作用，并且可能受到与慢性内脏痛相关的心理易损因素的调节。
