Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK.
University of Roehampton, London SW15 5PU.
Brain. 2017 Sep 1;140(9):2490-2497. doi: 10.1093/brain/awx170.
Individuals with schizophrenia typically suffer a range of cognitive deficits, including prominent deficits in working memory and executive function. These difficulties are strongly predictive of functional outcomes, but there is a paucity of effective therapeutic interventions targeting these deficits. Transcranial direct current stimulation is a novel neuromodulatory technique with emerging evidence of potential pro-cognitive effects; however, there is limited understanding of its mechanism. This was a double-blind randomized sham controlled pilot study of transcranial direct current stimulation on a working memory (n-back) and executive function (Stroop) task in 28 individuals with schizophrenia using functional magnetic resonance imaging. Study participants received 30 min of real or sham transcranial direct current stimulation applied to the left frontal cortex. The 'real' and 'sham' groups did not differ in online working memory task performance, but the transcranial direct current stimulation group demonstrated significant improvement in performance at 24 h post-transcranial direct current stimulation. Transcranial direct current stimulation was associated with increased activation in the medial frontal cortex beneath the anode; showing a positive correlation with consolidated working memory performance 24 h post-stimulation. There was reduced activation in the left cerebellum in the transcranial direct current stimulation group, with no change in the middle frontal gyrus or parietal cortices. Improved performance on the executive function task was associated with reduced activity in the anterior cingulate cortex. Transcranial direct current stimulation modulated functional activation in local task-related regions, and in more distal nodes in the network. Transcranial direct current stimulation offers a potential novel approach to altering frontal cortical activity and exerting pro-cognitive effects in schizophrenia.
个体患有精神分裂症通常会遭受一系列认知缺陷，包括工作记忆和执行功能的明显缺陷。这些困难强烈预测了功能结果，但针对这些缺陷的有效治疗干预措施却很少。经颅直流电刺激是一种新颖的神经调节技术，具有潜在的认知促进作用的新证据；然而，对其机制的理解有限。这是一项双盲随机假对照研究，研究了 28 名精神分裂症患者的经颅直流电刺激对工作记忆（n-back）和执行功能（Stroop）任务的影响，使用功能磁共振成像。研究参与者接受了 30 分钟的真实或假经颅直流电刺激，刺激部位为左额叶皮层。“真实”和“假”组在在线工作记忆任务表现上没有差异，但经颅直流电刺激组在经颅直流电刺激后 24 小时表现出显著的性能提高。经颅直流电刺激与阳极下方的内侧额叶皮层的激活增加有关；在刺激后 24 小时与巩固的工作记忆表现呈正相关。经颅直流电刺激组左小脑的激活减少，而额中回和顶叶皮层没有变化。执行功能任务的表现改善与前扣带皮层的活性降低有关。经颅直流电刺激调节了局部任务相关区域的功能激活，以及网络中更远端的节点。经颅直流电刺激为改变额叶皮层活动和发挥精神分裂症中的认知促进作用提供了一种潜在的新方法。
