Dressing Andrea, Martin Markus, Beume Lena-Alexandra, Kuemmerer Dorothee, Urbach Horst, Kaller Christoph P, Weiller Cornelius, Rijntjes Michel
Department of Neurology and Clinical Neuroscience, University Medical Center Freiburg, University of Freiburg, Freiburg i.Br., Germany; Freiburg Brain Imaging Center, University of Freiburg, Freiburg i.Br., Germany; BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, Freiburg i.Br., Germany.
Department of Neurology and Clinical Neuroscience, University Medical Center Freiburg, University of Freiburg, Freiburg i.Br., Germany; Freiburg Brain Imaging Center, University of Freiburg, Freiburg i.Br., Germany; BrainLinks-BrainTools Cluster of Excellence, University of Freiburg, Freiburg i.Br., Germany.
Cortex. 2020 Nov;132:166-179. doi: 10.1016/j.cortex.2020.07.017. Epub 2020 Sep 2.
Apraxia is frequently described after left hemisphere stroke and results from lesions to a complex network for motor cognition with dorso-dorsal, ventro-dorsal and ventral processing streams. Apraxia also occurs after right hemisphere stroke, but lesion correlates and underlying mechanisms remain to be elucidated. To clarify the role of the right hemisphere in apraxic deficits and the influence of neglect, we prospectively examined apraxia (imitation of meaningless postures and pantomime of tool use) and neglect in 138 acute right hemisphere stroke patients with first-ever ischemic stroke in the middle cerebral artery territory and identified corresponding lesion correlates using voxel-based lesion-symptom mapping. Imitation of meaningless postures was impaired as frequently as after left hemisphere stroke (38.4%) and was significantly associated with neglect. Imitation of meaningless postures was related to temporal (middle temporal gyrus, temporoparietal junction, superior temporal gyrus and sulcus), parietal (angular gyrus, parieto-occpitpial sulcus), secondary sensorimotor cortex and (peri-)insular lesions. Presence of neglect dichotomized the results: a lesion correlate for isolated imitation without neglect was found in the right parieto-occipital cortex, while imitation deficits, when co-occurring with neglect, were related to lateral occipito-temporal, superior temporal sulcus and (peri-)insular lesions. Pantomime of tool use deficits, typical for apraxia after left hemisphere lesions, were found in only 5 cases (3.6%) and only in the context of neglect, and were associated with occipital lobe, ventral and anterior temporal lobe, and inferior frontal (areas 45/47) lesions. The syndrome of apraxia after right hemisphere stroke differs from apraxia after left hemisphere stroke. Imitation deficits are found in both hemispheres after dorso-dorsal stream lesions. Neglect also leads to and explains deficits in imitation and pantomime in patients with right ventral stream lesions. Therefore, in right hemisphere lesions, apraxia can either be explained as impaired visuomotor transformation or as a result of visuospatial deficits.
失用症常见于左半球卒中后，是由涉及背侧、腹背侧和腹侧加工流的复杂运动认知网络受损所致。右半球卒中后也会出现失用症，但其病变相关性及潜在机制仍有待阐明。为明确右半球在失用症缺陷中的作用以及忽视的影响，我们对138例首次发生于大脑中动脉区域的急性右半球缺血性卒中患者进行了前瞻性研究，观察了失用症（模仿无意义姿势和工具使用手势）及忽视情况，并采用基于体素的病变-症状映射确定相应的病变相关性。模仿无意义姿势受损的发生率与左半球卒中后相当（38.4%），且与忽视显著相关。模仿无意义姿势与颞叶（颞中回、颞顶交界区、颞上回和颞上沟）、顶叶（角回、顶枕沟）、二级感觉运动皮层及（周围）岛叶病变有关。忽视的存在使结果出现二分法：在无忽视的单纯模仿中，病变相关性位于右侧顶枕叶皮层；而当模仿缺陷与忽视同时出现时，则与枕颞外侧、颞上沟及（周围）岛叶病变有关。左半球病变后典型的工具使用手势缺陷仅在5例（3.6%）患者中出现，且仅在存在忽视的情况下出现，与枕叶、颞叶腹侧和前侧及额下回（45/47区）病变有关。右半球卒中后的失用症综合征与左半球卒中后的不同。背侧流病变后，双侧半球均会出现模仿缺陷。忽视也会导致并解释右腹侧流病变患者的模仿和手势缺陷。因此，在右半球病变中，失用症既可以解释为视觉运动转换受损，也可以解释为视觉空间缺陷的结果。
