Real-time functional MRI neurofeedback allows individuals to self-modulate their ongoing brain activity. This may be a useful tool in clinical disorders that are associated with altered brain activity patterns. Motor impairment after stroke has previously been associated with decreased laterality of motor cortex activity. Here we examined whether chronic stroke survivors were able to use real-time fMRI neurofeedback to increase laterality of motor cortex activity and assessed effects on motor performance and on brain structure and function. We carried out a randomized, double-blind, sham-controlled trial (ClinicalTrials.gov: NCT03775915) in which 24 chronic stroke survivors with mild to moderate upper limb impairment experienced three training days of either Real (n = 12) or Sham (n = 12) neurofeedback. Assessments of brain structure, brain function and measures of upper-limb function were carried out before and 1 week after neurofeedback training. Additionally, measures of upper-limb function were repeated 1 month after neurofeedback training. Primary outcome measures were (i) changes in lateralization of motor cortex activity during movements of the stroke-affected hand throughout neurofeedback training days; and (ii) changes in motor performance of the affected limb on the Jebsen Taylor Test (JTT). Stroke survivors were able to use Real neurofeedback to increase laterality of motor cortex activity within (P = 0.019), but not across, training days. There was no group effect on the primary behavioural outcome measure, which was average JTT performance across all subtasks (P = 0.116). Secondary analysis found improvements in the performance of the gross motor subtasks of the JTT in the Real neurofeedback group compared to Sham (P = 0.010). However, there were no improvements on the Action Research Arm Test or the Upper Extremity Fugl–Meyer score (both P > 0.5). Additionally, decreased white-matter asymmetry of the corticospinal tracts was detected 1 week after neurofeedback training (P = 0.008), indicating that the tracts become more similar with Real neurofeedback. Changes in the affected corticospinal tract were positively correlated with participants neurofeedback performance (P = 0.002). Therefore, here we demonstrate that chronic stroke survivors are able to use functional MRI neurofeedback to self-modulate motor cortex activity in comparison to a Sham control, and that training is associated with improvements in gross hand motor performance and with white matter structural changes.

中文翻译：

---

中风后运动皮层活动的自我调节：一项随机对照试验

实时功能性 MRI 神经反馈允许个人自我调节他们正在进行的大脑活动。这可能是与大脑活动模式改变相关的临床疾病的有用工具。中风后的运动障碍以前与运动皮层活动的侧向性降低有关。在这里，我们检查了慢性中风幸存者是否能够使用实时 fMRI 神经反馈来增加运动皮层活动的偏侧性，并评估对运动表现和大脑结构和功能的影响。我们开展了一项随机、双盲、假对照试验（ClinicalTrials.gov：NCT03775915），其中 24 名患有轻度至中度上肢损伤的慢性中风幸存者经历了三天的真实（n = 12）或假（n = 12) 神经反馈。大脑结构评估，在神经反馈训练之前和之后1周进行脑功能和上肢功能测量。此外，在神经反馈训练后 1 个月重复测量上肢功能。主要结果测量是（i）在整个神经反馈训练日中中风影响手的运动过程中运动皮层活动的侧化变化；(ii) Jebsen Taylor 测试 (JTT) 中受影响肢体的运动表现变化。中风幸存者能够使用真正的神经反馈来增加运动皮层活动的侧向性（P = 0.019），但不能跨越训练日。主要行为结果测量没有群体效应，即所有子任务的平均 JTT 表现（P = 0.116）。二次分析发现，与 Sham 相比，真实神经反馈组中 JTT 的粗大运动子任务的性能有所改善（P = 0.010）。然而，Action Research Arm Test 或上肢 Fugl-Meyer 评分没有改善（均 P > 0.5）。此外，在神经反馈训练后 1 周检测到皮质脊髓束的白质不对称性降低（P = 0.008），表明这些束变得与真正的神经反馈更加相似。受影响的皮质脊髓束的变化与参与者的神经反馈表现呈正相关（P = 0.002）。因此，我们在此证明，与 Sham 对照相比，慢性中风幸存者能够使用功能性 MRI 神经反馈来自我调节运动皮层活动，