Laboratory of Cognitive Neuroscience, Brain Mind Institute, EPFL, Switzerland.
Center for Neuroprosthetics, School of Life Sciences, EPFL, Switzerland.
J Neuropsychol. 2018 Sep;12(3):442-462. doi: 10.1111/jnp.12123. Epub 2017 Apr 17.
The symptoms of patients with left personal neglect are characterized by inattention towards contralesional (left) body parts while at the same time explicitly ascertaining ownership for the neglected hemibody. It is currently unknown if personal neglect is associated with more subtle or implicit disturbances of own body perception and body ownership as measured with the rubber hand illusion. In this study, we report data from a patient with a right hemispheric lesion and personal neglect, without associated somatosensory deficits. We administered to the patient (and to 12 age-matched controls) the rubber hand illusion paradigm to the right and left hands, to elicit illusory ownership for a fake hand, before and after recovery from personal neglect for the left arm. In a first session, run when the patient showed personal neglect affecting the left arm, he experienced a significantly enhanced subjective illusion of embodiment for the left fake hand as compared to the right hand (as assessed through a standard questionnaire). After recovery from personal neglect for the left arm (second session), the results of the left and right rubber hand illusion experiments were comparable, with no modulation of hand ownership. We argue that personal neglect may consist not only in an inattentional disorder, but also in a deficit of multisensory body representation characterized by a high sensitivity to experimental manipulations of subjective aspects of body ownership.
患者左侧个人忽略的症状表现为对病变对侧（左侧）身体部位的注意力不集中，同时明确确定忽略的身体部分归属于自身。目前尚不清楚个人忽略是否与更微妙或隐性的自身身体感知和身体所有权障碍有关，这些障碍可以通过橡胶手错觉来衡量。在这项研究中，我们报告了一位右侧半球病变和个人忽略的患者的数据，该患者没有伴随躯体感觉缺陷。我们向患者（和 12 位年龄匹配的对照者）的右手和左手施加了橡胶手错觉范式，以在左手臂的个人忽略恢复之前和之后，诱发出对假手的虚幻所有权。在第一次测试中，当患者出现影响左臂的个人忽略时，他体验到对左侧假手的虚幻身体感觉明显增强（通过标准问卷评估）。在左臂的个人忽略恢复后（第二次测试），左右橡胶手错觉实验的结果相当，对手所有权没有调节。我们认为，个人忽略可能不仅包括注意力障碍，还包括多感觉身体表现的缺陷，其特征是对身体所有权的主观方面的实验操作具有高度敏感性。
