Department of Communication Sciences & Disorders, University of South Carolina, USA.
Department of Public Health Sciences, Medical University of South Carolina, USA.
Brain Stimul. 2018 Nov-Dec;11(6):1276-1281. doi: 10.1016/j.brs.2018.08.009. Epub 2018 Aug 18.
Several studies, including a randomized controlled trial by our group, support applying anodal tDCS (A-tDCS) to the left hemisphere during behavioral aphasia treatment to improve outcomes. A clear mechanism explaining A-tDCS's efficacy has not been established, but modulation of neuroplasticity may be involved.
OBJECTIVE/HYPOTHESIS: The brain-derived neurotrophic factor (BDNF) gene influences neuroplasticity and may modulate the effects of tDCS. Utilizing data from our recently completed trial, we conducted a planned test of whether aphasia treatment outcome is influenced by interaction between A-tDCS and a single-nucleotide polymorphism of the BDNF gene, rs6265.
Seventy-four individuals with chronic stroke-induced aphasia completed 15 language therapy sessions and were randomized to receive 1 mA A-tDCS or sham tDCS (S-tDCS) to the intact left temporoparietal region for the first 20 min of each session. BDNF genotype was available for 67 participants: 37 participants had the typical val/val genotype. The remaining 30 participants had atypical BDNF genotype (Met allele carriers). The primary outcome factor was improvement in object naming at 1 week after treatment completion. Maintenance of treatment effects was evaluated at 4 and 24 weeks.
An interaction was revealed between tDCS condition and genotype for treatment-related naming improvement (F = 4.97, p = 0.03). Participants with val/val genotype who received A-tDCS showed greater response to aphasia treatment than val/val participants who received S-tDCS, as well as the Met allele carriers, regardless of tDCS condition.
Individuals with the val/val BDNF genotype are more likely to benefit from A-tDCS during aphasia treatment.
包括我们团队进行的一项随机对照试验在内的几项研究支持在行为性失语症治疗中对左侧大脑半球施加阳极经颅直流电刺激（A-tDCS）以改善治疗效果。目前尚未确定 A-tDCS 疗效的确切机制，但神经可塑性的调节可能与之相关。
目的/假设：脑源性神经营养因子（BDNF）基因影响神经可塑性，并可能调节 tDCS 的作用。利用我们最近完成的试验数据，我们进行了一项计划中的检验，即 A-tDCS 与 BDNF 基因单核苷酸多态性 rs6265 的相互作用是否会影响失语症治疗效果。
74 名慢性卒中后失语症患者完成了 15 次语言治疗课程，并随机分为 A-tDCS 组或假刺激 tDCS（S-tDCS）组，在每次治疗的前 20 分钟接受 1 mA 的刺激。BDNF 基因型可用于 67 名参与者：37 名参与者具有典型的 val/val 基因型。其余 30 名参与者具有非典型 BDNF 基因型（Met 等位基因携带者）。主要结局因素是治疗完成后 1 周时的物体命名改善情况。在治疗后 4 周和 24 周评估治疗效果的维持情况。
tDCS 条件和基因型之间存在治疗相关命名改善的交互作用（F=4.97，p=0.03）。接受 A-tDCS 的 val/val 基因型参与者的失语症治疗反应优于接受 S-tDCS 的 val/val 参与者，以及接受任何 tDCS 条件的 Met 等位基因携带者。
BDNF 基因 val/val 基因型的个体在失语症治疗期间更有可能从 A-tDCS 中受益。
