Enhancing Cognitive Training with Transcranial Direct Current Stimulation

确定可以带来认知益处的干预措施可能对教育、成功老龄化和改善认知能力下降具有广泛的意义。关于工作记忆的训练是否可以增强认知功能，人们进行了密集的调查，但结果存在争议。然而，最近有证据表明，工作记忆和其他认知技能的认知训练可以从训练期间应用的非侵入性脑刺激中受益。特别是，在头皮的特定区域反复应用直流电刺激可以改善旨在改善工作记忆的训练计划的结果。此外，在没有后续训练或刺激的情况下，这种增强效果在训练后长达几个月或一年后保持不变。在这项拟议的研究中，我们检查了这种改善可能发生的神经生物学机制。鉴于直流电刺激的潜在有效性、可及性和低成本，了解刺激发挥作用的神经机制可能对构建更有效的干预措施具有直接意义。电流刺激对记忆产生促进作用的神经机制在很大程度上是未知的。该研究项目将结合经颅直流电刺激和同步功能神经成像来检查刺激对潜在神经活动的影响。受试者将接受为期数天的短期记忆任务训练，并在训练进行时进行扫描。收集的神经成像数据将测量在训练过程中伴随刺激的局部灌注阶段，当伴随着不同类型的经颅刺激时。这些研究将1)比较在训练干预过程中学习进行时有无刺激的网络连通性，以及2)比较阳极和阴极颠倒时刺激对神经活动的影响。在工作记忆任务中，电极放置位置将根据每个参与者的个体激活模式进行优化调整。这些研究的结果将解决工作记忆训练与直接皮质刺激所导致的认知变化的性质，以及这些变化与神经活动模式的关系。

Identifying interventions that can lead to cognitive benefits may have broad implications for education, successful aging, and amelioration of cognitive decline. There has been intense investigation of whether the training of working memory can enhance cognitive functioning, but with controversial outcomes. There is however recent evidence that cognitive training of working memory and other cognitive skills can benefit from non-invasive brain stimulation applied during training. In particular, repeated application of direct current stimulation to certain regions of the scalp can improve the outcomes of a training program intended to improve working memory. Furthermore, this enhancement effect is maintained after for up to several months or a year post-training without subsequent training or stimulation. In the proposed research, we examine the neurobiological mechanisms by which this improvement may occur. Given the potential effectiveness of direct current stimulation, its accessibility and low cost, understanding the neural mechanisms by which stimulation exerts its effects could have direct implications for constructing more effective interventions. The neural mechanisms by which current stimulation achieves its facilitative effects on memory are largely unknown. The research program will combine transcranial direct current stimulation with simultaneous functional neuroimaging to examine the effect of stimulation on underlying neural activity. Individuals will be trained on a short-term memory task for several days and will be scanned as training proceeds. The neuroimaging data collected will measure local perfusion stages that accompany the stimulation during the training itself, when accompanied by different types of transcranial stimulation. The studies will 1) compare network connectivity with and without stimulation as learning proceeds over the course of a training intervention and 2) compare the impact of stimulation on neural activity when the anode and cathode are reversed. Electrode placement sites will be optimally adjusted based on each participant's individual activation patterns during a working memory task. The results of these studies will address the nature of the cognitive changes due to working memory training with direct cortical stimulation as well as the relationship of these changes to patterns of neural activity.