School of Psychology, University of Sussex, Brighton, UK.
Sackler Centre for Consciousness Science, Brighton, UK.
Q J Exp Psychol (Hove). 2021 Nov;74(11):1888-1899. doi: 10.1177/17470218211024822. Epub 2021 Jun 29.
Some people report localised pain on their body when seeing other people in pain (sensory-localised vicarious pain responders). In this study, we assess whether this is related to atypical computations of body ownership which, in paradigms such as the rubber hand illusion (RHI), can be conceptualised as a Bayesian inference as to whether multiple sources of sensory information (visual, somatosensory) belong together on a single body (one's own) or are distributed across several bodies (vision = other, somatosensory = self). According to this model, computations of body ownership depend on the degree (and precision) of sensory evidence, rather than synchrony per se. Sensory-localised vicarious pain responders exhibit the RHI following synchronous stroking and-unusually-also after asynchronous stroking. Importantly, this occurs only in asynchronous conditions in which the stroking is predictable (alternating) rather than unpredictable (random). There was no evidence that their bottom-up proprioceptive signals are less precise, suggesting individual differences in the top-down weighting of sensory evidence. Finally, the enfacement illusion (EI) was also employed as a conceptually related bodily illusion paradigm that involves a completely different response judgement (based on vision rather than proprioception). Sensory-localised responders show a comparable pattern on this task after synchronous and asynchronous stroking. This is consistent with the idea that they have top-down (prior) differences in the way body ownership is inferred that transcends the exact judgement being made (visual or proprioceptive).
当看到别人疼痛时，有些人会在自己身上感觉到局部疼痛（感知局部的替代性疼痛反应者）。在这项研究中，我们评估了这种情况是否与身体所有权的非典型计算有关，在橡胶手错觉（RHI）等范式中，这种计算可以被概念化为对多个来源的感觉信息（视觉、体感）是否属于单个身体（自己的）或分布在多个身体上（视觉=他人，体感=自己）的贝叶斯推断。根据这个模型，身体所有权的计算取决于感觉证据的程度（和精度），而不是同步本身。感知局部的替代性疼痛反应者在同步和非同步刺激后都会出现 RHI，这是异常的。重要的是，这种情况仅发生在刺激可预测（交替）而非不可预测（随机）的非同步条件下。没有证据表明他们的本体感觉信号不那么精确，这表明个体对感觉证据的自上而下权重存在差异。最后，还使用了面部错觉（EI）作为一个概念上相关的身体错觉范式，它涉及到一个完全不同的反应判断（基于视觉而不是本体感觉）。在这个任务中，感知局部的反应者在同步和非同步刺激后表现出类似的模式。这与他们在推断身体所有权时存在自上而下（先验）差异的观点一致，这种差异超越了正在进行的视觉或本体感觉判断。
