Saetta Gianluca, Zindel-Geisseler Olivia, Stauffacher Franziska, Serra Carlo, Vannuscorps Gilles, Brugger Peter
Neuropsychology Unit, University Hospital Zurich, Zurich, Switzerland.
Department of Psychology, University of Zurich, Zurich, Switzerland.
Front Psychol. 2021 Jan 14;11:544544. doi: 10.3389/fpsyg.2020.544544. eCollection 2020.
Asomatognosia designates the experience that one's body has faded from awareness. It is typically a somaesthetic experience but may target the visual modality ("asomatoscopy"). Frequently associated symptoms are the loss of ownership or agency over a limb. Here, we elaborate on the rigorous nosographic classification of asomatognosia and introduce a structured interview to capture both its core symptoms and associated signs of bodily estrangement. We additionally report the case of a pure left-sided hemiasomatognosia occurring after surgical removal of a meningioma in the right atrium. Despite the wide lesions of the right angular gyrus and of the temporo-parietal junction, the patient did not present visuospatial deficits or bodily awareness disorders other than hemiasomatognosia. The patient and 10 matched controls' motor imagery was formally assessed with a limb laterality task in which they had to decide whether hands and feet presented under different angles of rotation depicted a left or a right limb. Bayesian statistics showed that patient's reaction times were significantly impaired exclusively for the left foot and especially for mental rotations requiring somatomotor rather than visual limb representations. This was in accordance with a more enduring left-sided hemiasomatognosia for the lower limbs confined to the somesthetic modality. Our findings shed new light on motor imagery in asomatognosia and encourage the future use of the structured interview introduced here. In addition, the limb laterality task may capture phenomenological elements of a case by chronometric means. This allows a more standardized reporting of phenomenological detail and improves communication across different clinical facilities.
自体失认症指的是身体从意识中消退的体验。它通常是一种躯体感觉体验，但也可能针对视觉模态（“自体视诊”）。常见的相关症状是对肢体失去所有权或控制感。在此，我们详细阐述了自体失认症严格的疾病分类，并介绍了一种结构化访谈，以捕捉其核心症状和身体疏离的相关体征。我们还报告了一例在手术切除右心房脑膜瘤后出现的单纯左侧半身自体失认症病例。尽管右侧角回和颞顶叶交界处有广泛病变，但除半身自体失认症外，患者未出现视觉空间缺陷或身体意识障碍。通过一项肢体侧性任务对患者和10名匹配的对照者的运动想象进行了正式评估，在该任务中，他们必须判断以不同旋转角度呈现的手和脚描绘的是左肢还是右肢。贝叶斯统计显示，患者的反应时间仅在左脚方面显著受损，尤其是对于需要躯体运动而非视觉肢体表征的心理旋转。这与局限于躯体感觉模态的下肢更持久的左侧半身自体失认症一致。我们的研究结果为自体失认症中的运动想象提供了新的见解，并鼓励未来使用此处介绍的结构化访谈。此外，肢体侧性任务可以通过计时手段捕捉病例的现象学要素。这允许对现象学细节进行更标准化的报告，并改善不同临床机构之间的交流。
