PDF(Pubmed)
Abstract：
UNASSIGNED: Homonymous visual field defects (HVFDs) following acquired brain lesions affect independent living by hampering several activities of everyday life. Available treatments are intensive and week- or month-long. Transcranial Direct current stimulation (tDCS), a plasticity-modulating non-invasive brain stimulation technique, could be combined with behavioral trainings to boost their efficacy or reduce treatment duration. Some promising attempts have been made pairing occipital tDCS with visual restitution training, however less is knows about which area/network should be best stimulated in association with compensatory approaches, aimed at improving exploratory abilities, such as multisensory trainings.
UNASSIGNED: In a proof-of-principle, sham-controlled, single-blind study, 15 participants with chronic HVFDs underwent four one-shot sessions of active or sham anodal tDCS applied over the ipsilesional occipital cortex, the ipsilesional or contralesional posterior parietal cortex. tDCS was delivered during a compensatory multisensory (audiovisual) training. Before and immediately after each tDCS session, participants carried out a visual detection task, and two visual search tasks (EF and Triangles search tests). Accuracy (ACC) and response times (RTs) were analyzed with generalized mixed models. We investigated differences in baseline performance, clinical-demographic and lesion factors between tDCS responders and non-responders, based on post-tDCS behavioral improvements. Lastly, we conducted exploratory analyses to compare left and right brain-damaged participants.
UNASSIGNED: RTs improved after active ipsilesional occipital and parietal tDCS in the visual search tasks, while no changes in ACC were detected. Responders to ipsilesional occipital tDCS (Triangle task) had shorter disease duration and smaller lesions of the parietal cortex and the superior longitudinal fasciculus. On the other end, on the EF test, those participants with larger damage of the temporo-parietal cortex or the fronto-occipital white matter tracts showed a larger benefit from contralesional parietal tDCS. Overall, the visual search RTs improvements were larger in participants with right-sided hemispheric lesions.
UNASSIGNED: The present result shows the facilitatory effects of occipital and parietal tDCS combined with compensatory multisensory training on visual field exploration in HVFDs, suggesting a potential for the development of new neuromodulation treatments to improve visual scanning behavior in brain-injured patients.
UNASSIGNED: In a proof-of-principle, sham-controlled, single-blind study, 15 participants with chronic HVFDs underwent four one-shot sessions of active or sham anodal tDCS applied over the ipsilesional occipital cortex, the ipsilesional or contralesional posterior parietal cortex. tDCS was delivered during a compensatory multisensory (audiovisual) training. Before and immediately after each tDCS session, participants carried out a visual detection task, and two visual search tasks (EF and Triangles search tests). Accuracy (ACC) and response times (RTs) were analyzed with generalized mixed models. We investigated differences in baseline performance, clinical-demographic and lesion factors between tDCS responders and non-responders, based on post-tDCS behavioral improvements. Lastly, we conducted exploratory analyses to compare left and right brain-damaged participants.
UNASSIGNED: RTs improved after active ipsilesional occipital and parietal tDCS in the visual search tasks, while no changes in ACC were detected. Responders to ipsilesional occipital tDCS (Triangle task) had shorter disease duration and smaller lesions of the parietal cortex and the superior longitudinal fasciculus. On the other end, on the EF test, those participants with larger damage of the temporo-parietal cortex or the fronto-occipital white matter tracts showed a larger benefit from contralesional parietal tDCS. Overall, the visual search RTs improvements were larger in participants with right-sided hemispheric lesions.
UNASSIGNED: The present result shows the facilitatory effects of occipital and parietal tDCS combined with compensatory multisensory training on visual field exploration in HVFDs, suggesting a potential for the development of new neuromodulation treatments to improve visual scanning behavior in brain-injured patients.
摘要：
■获得性脑损伤后的同名视野缺陷（HVFD）通过阻碍日常生活的几种活动来影响独立生活。可用的治疗是密集的，为期一周或一个月。经颅直流电刺激(tDCS),可塑性调节非侵入性脑刺激技术，可以与行为训练相结合，以提高疗效或减少治疗持续时间。一些有希望的尝试是将枕骨tDCS与视觉恢复训练配对，然而，很少有人知道哪个区域/网络应该与补偿性方法相结合得到最好的刺激，旨在提高探索能力，如多感官训练。
■在原理证明中，假控制，单盲研究,15名患有慢性HVFD的参与者接受了四次一次性的活动或假阳极tDCS，后顶叶皮质的同侧或对侧。tDCS是在补偿性多感觉（视听）训练期间提供的。在每个tDCS会话之前和之后，参与者进行了视觉检测任务，和两个视觉搜索任务（EF和三角形搜索测试）。使用广义混合模型分析了精度（ACC）和响应时间（RTs）。我们调查了基线性能的差异，tDCS应答者和无应答者之间的临床人口统计学和病变因素，基于tDCS后的行为改进。最后,我们进行了探索性分析,以比较左右脑受损的参与者.
■在视觉搜索任务中活跃的枕骨和顶骨tDCS后，RTs得到改善，而未检测到ACC的变化。患侧枕骨tDCS（三角形任务）的反应者的疾病持续时间较短，顶叶皮层和上纵束的病变较小。在另一端,在EF测试中，颞顶叶皮质或额枕骨白质束损伤较大的参与者显示,对侧顶叶tDCS获益较大.总的来说,右侧半球病变参与者的视觉搜索RT改善更大.
■本结果显示枕顶tDCS结合代偿性多感觉训练对HVFD视野探索的促进作用，提示开发新的神经调节疗法以改善脑损伤患者的视觉扫描行为的潜力。
■在原理证明中，假控制，单盲研究,15名患有慢性HVFD的参与者接受了四次一次性的活动或假阳极tDCS，后顶叶皮质的同侧或对侧。tDCS是在补偿性多感觉（视听）训练期间提供的。在每个tDCS会话之前和之后，参与者进行了视觉检测任务，和两个视觉搜索任务（EF和三角形搜索测试）。使用广义混合模型分析了精度（ACC）和响应时间（RTs）。我们调查了基线性能的差异，tDCS应答者和无应答者之间的临床人口统计学和病变因素，基于tDCS后的行为改进。最后,我们进行了探索性分析,以比较左右脑受损的参与者.
■在视觉搜索任务中活跃的枕骨和顶骨tDCS后，RTs得到改善，而未检测到ACC的变化。患侧枕骨tDCS（三角形任务）的反应者的疾病持续时间较短，顶叶皮层和上纵束的病变较小。在另一端,在EF测试中，颞顶叶皮质或额枕骨白质束损伤较大的参与者显示,对侧顶叶tDCS获益较大.总的来说,右侧半球病变参与者的视觉搜索RT改善更大.
■本结果显示枕顶tDCS结合代偿性多感觉训练对HVFD视野探索的促进作用，提示开发新的神经调节疗法以改善脑损伤患者的视觉扫描行为的潜力。
