Inserm UMR-S 1127, UPMC-Paris 6, CNRS UMR 7225, Brain and Spine Institute, Groupe Hospitalier Pitié-Salpêtrière Paris, France ; Fédération de Neurologie, IM2A, AP-HP, Groupe Hospitalier Pitié-Salpêtrière Paris, France ; Department of Psychology, Catholic University Milan, Italy.
Inserm UMR-S 1127, UPMC-Paris 6, CNRS UMR 7225, Brain and Spine Institute, Groupe Hospitalier Pitié-Salpêtrière Paris, France.
Front Hum Neurosci. 2014 Jun 11;8:408. doi: 10.3389/fnhum.2014.00408. eCollection 2014.
Motor neglect (MN) is a clinically important condition whereby patients with unilateral brain lesions fail to move their contralateral limbs, despite normal muscle strength, reflexes, and sensation. MN has been associated with various lesion sites, including the parietal and frontal cortex, the internal capsule, the lenticulostriate nuclei, and the thalamus. In the present study, we explored the hypothesis that MN depends on a dysfunction of the medial motor system by performing a detailed anatomical analysis in four patients with MN.
Ten patients participated in the study: four with MN, four with left visual neglect but without MN, and three patients with left hemiplegia without MN. We used specific scales for clinical and neuropsychological assessment. We drew the lesion borders directly onto the original brain images of each patient, and plotted the lesions on anatomical atlases for gray and white matter.
Lesion locations were highly heterogeneous in our MN patients, and included frontal and parietal sites, basal ganglia, and white matter. The only consistently damaged structure across all MN patients was the cingulum bundle, a major pathway of the medial motor system important for motor initiative, and a key connection with limbic structures crucial for motivational aspects of actions. Three MN patients with additional damage to lateral fronto-parietal networks had also signs of contralesional visual neglect. The cingulum bundle was intact in all the control patients with visual neglect or hemiplegia.
Cingulum damage may induce MN through unilateral dysfunction of the medial motor system. Additional lateral fronto-parietal dysfunction can result in the association with visual neglect.
运动忽视（MN）是一种临床重要病症，表现为单侧大脑损伤的患者尽管肌肉力量、反射和感觉正常，但无法移动其对侧肢体。MN 与各种病变部位有关，包括顶叶和额叶皮层、内囊、纹状体核和丘脑。在本研究中，我们通过对 4 名 MN 患者进行详细的解剖学分析，提出了 MN 依赖于内侧运动系统功能障碍的假设。
10 名患者参与了研究：4 名 MN 患者，4 名左侧视觉忽视但无 MN 患者，3 名左侧偏瘫但无 MN 患者。我们使用特定的临床和神经心理学评估量表。我们直接在每位患者的原始脑图像上绘制病变边界，并在灰质和白质解剖图谱上绘制病变。
我们的 MN 患者的病变位置高度异质，包括额叶和顶叶部位、基底节和白质。所有 MN 患者一致受损的唯一结构是扣带束，这是内侧运动系统的主要通路，对运动主动性很重要，也是与对动作动机方面至关重要的边缘结构的关键连接。3 名 MN 患者伴有外侧额顶叶网络损伤，也有对侧视觉忽视的迹象。所有有视觉忽视或偏瘫的对照患者的扣带束都完好无损。
扣带束损伤可能通过内侧运动系统的单侧功能障碍引起 MN。额外的外侧额顶叶功能障碍可能导致与视觉忽视相关。
