Univ. Lille, Inserm, CHU Lille, U1172 - LilNCog - Lille Neuroscience & Cognition, Lille, France.
Institut de Neuropsychologie, Neurovision et Neurocognition, Fondation Ophtalmologique Rothschild, Paris, France; Integrative Neuroscience and Cognition Center - UMR 8002 CNRS/Université Paris Descartes, Paris, France.
Cortex. 2020 Jun;127:393-395. doi: 10.1016/j.cortex.2020.03.004. Epub 2020 Mar 24.
We recently published the results of a study on the occurrence of blindsight among eight, post-stroke homonymous hemianopic (HH) patients (Garric et al., 2019), in whom we measured blindsight through forced-choice tasks and assessed perceptual experiences by a new awareness scale, the Sensation Awareness Scale (SAS). Within the cohort, we found different profiles of dissociation between objective and subjective performance. Importantly, we were able to describe several cases of a dissociation phenomenon that we named blindsense, whereby patients exhibited marked subjective sensitivity in their blind hemifield despite being unable to discriminate the different stimuli. Following publication of our article (Garric et al., 2019), Prof. Ian Phillips (Phillips, 2019) wrote a Commentary in which he questioned the methodology we used to measure and analyze objective and subjective perception in our HH patients. As opposed to our original interpretation of our results to describe the new profile of blindsense, based on a non-visual experience hypothesis (Kentridge, 2015), Prof. Phillips re-evaluated the different blindsight profiles that we identified in our study through the lens of a degraded conscious vision hypothesis (Overgaard, Fehl, Mouridsen, Bergholt, & Cleeremans, 2008). In the present response, we explain that, although we agree that dichotomous visual scales lead to highly conservative responses and mask conscious perceptual experience of patients, we still support the notion that nuanced report protocols can enable more-sensitive measurements of perceptual experiences in the hemianopic, so-called blind visual field. Furthermore, we affirm that the additional awareness-scale phenomenal levels that such protocols enable are more consistent with patients' experiences and lead patients to provide more liberal responses when describing their subjective perceptions.
我们最近发表了一项关于 8 名卒中后同视性偏盲(HH)患者盲视发生率的研究结果(Garric 等人,2019 年),在这些患者中,我们通过强制选择任务测量盲视,并使用新的意识量表——感觉意识量表(SAS)评估感知体验。在该队列中,我们发现了客观和主观表现之间不同的分离模式。重要的是,我们能够描述几种我们称之为盲感的分离现象,即患者在其盲侧视野中表现出明显的主观敏感性,尽管他们无法辨别不同的刺激。在我们的文章发表后(Garric 等人,2019 年),Ian Phillips 教授(Phillips,2019 年)写了一篇评论,对我们在 HH 患者中用于测量和分析客观和主观感知的方法提出了质疑。与我们基于非视觉体验假说(Kentridge,2015 年)对我们的研究结果进行新的盲感描述的原始解释相反,Phillips 教授通过受损意识视觉假说(Overgaard、Fehl、Mouridsen、Bergholt 和 Cleeremans,2008 年)重新评估了我们在研究中确定的不同盲视模式。在本回应中,我们解释说,尽管我们同意二分视觉量表导致高度保守的反应并掩盖了患者的意识感知体验,但我们仍然支持这样的观点,即细微的报告方案可以使半盲患者的感知体验更敏感地测量,所谓的盲视场。此外,我们肯定这些方案能够实现的额外的意识量表现象水平与患者的体验更一致,并使患者在描述其主观感知时提供更自由的反应。