School of Psychology, University of Kent Canterbury, UK.
East Kent Neuro-Rehabilitation Service, East Kent Hospitals University NHS Foundation Trust Canterbury, UK.
Front Integr Neurosci. 2014 Jan 29;8:4. doi: 10.3389/fnint.2014.00004. eCollection 2014.
Hemi-spatial neglect is an attentional disorder in which the sufferer fails to acknowledge or respond to stimuli appearing in contralesional space. In recent years, it has become clear that a measurable reduction in contralesional neglect can occur during galvanic vestibular stimulation, a technique by which transmastoid, small amplitude current induces lateral, attentional shifts via asymmetric modulation of the left and right vestibular nerves. However, it remains unclear whether this reduction persists after stimulation is stopped. To estimate longevity of effect, we therefore conducted a double-blind, randomized, dose-response trial involving a group of stroke patients suffering from left-sided neglect (n = 52, mean age = 66 years). To determine whether repeated sessions of galvanic vestibular stimulation more effectively induce lasting relief than a single session, participants received 1, 5, or 10 sessions, each lasting 25 min, of sub-sensory, left-anodal right-cathodal noisy direct current (mean amplitude = 1 mA). Ninety five percent confidence intervals indicated that all three treatment arms showed a statistically significant improvement between the pre-stimulation baseline and the final day of stimulation on the primary outcome measure, the conventional tests of the Behavioral Inattention Test. More remarkably, this change (mean change = 28%, SD = 18) was still evident 1 month later. Secondary analyses indicated an allied increase of 20% in median Barthel Index (BI) score, a measure of functional capacity, in the absence of any adverse events or instances of participant non-compliance. Together these data suggest that galvanic vestibular stimulation, a simple, cheap technique suitable for home-based administration, may produce lasting reductions in neglect that are clinically important. Further protocol optimization is now needed ahead of a larger effectiveness study.
半侧空间忽略是一种注意力障碍，患者无法意识到或对出现在对侧空间的刺激做出反应。近年来，人们已经清楚地认识到，在经颅直流电刺激（galvanic vestibular stimulation，GVS）过程中，对侧忽略的程度可以明显降低。这种技术通过在乳突部位施加小幅度的电流，通过对左右前庭神经的不对称调制，引起侧向的注意力转移。然而，目前尚不清楚刺激停止后这种降低是否仍然存在。为了估计效果的持续时间，我们因此进行了一项双盲、随机、剂量反应试验，涉及 52 名患有左侧忽略的中风患者（平均年龄为 66 岁）。为了确定重复进行经颅直流电刺激是否比单次治疗更有效地诱导持久缓解，参与者接受了 1、5 或 10 次 25 分钟的亚感觉、左阳极右阴极噪声直流电刺激（平均幅度为 1 mA）。95%置信区间表明，所有三个治疗组在主要结局测量——行为忽视测试的常规测试中，都显示出从刺激前基线到刺激最后一天的统计学显著改善。更值得注意的是，这种变化（平均变化=28%，SD=18%）在 1 个月后仍然明显。二次分析表明，在没有任何不良事件或参与者不遵守的情况下，功能能力的中位数巴氏量表（BI）评分也相应增加了 20%。这些数据表明，经颅直流电刺激，一种简单、廉价、适合家庭管理的技术，可能会产生持久的忽略减少，这在临床上是重要的。在进行更大规模的有效性研究之前，现在需要进一步优化方案。
