Beuter Anne, Balossier Anne, Vassal François, Hemm Simone, Volpert Vitaly
Bordeaux INP, University of Bordeaux, Bordeaux, France.
Service de neurochirurgie fonctionnelle et stéréotaxique, AP-HM La Timone, Aix-Marseille University, Marseille, France.
Biol Cybern. 2020 Feb;114(1):5-21. doi: 10.1007/s00422-020-00818-w. Epub 2020 Feb 4.
The aim of this paper is to integrate different bodies of research including brain traveling waves, brain neuromodulation, neural field modeling and post-stroke language disorders in order to explore the opportunity of implementing model-guided, cortical neuromodulation for the treatment of post-stroke aphasia. Worldwide according to WHO, strokes are the second leading cause of death and the third leading cause of disability. In ischemic stroke, there is not enough blood supply to provide enough oxygen and nutrients to parts of the brain, while in hemorrhagic stroke, there is bleeding within the enclosed cranial cavity. The present paper focuses on ischemic stroke. We first review accumulating observations of traveling waves occurring spontaneously or triggered by external stimuli in healthy subjects as well as in patients with brain disorders. We examine the putative functions of these waves and focus on post-stroke aphasia observed when brain language networks become fragmented and/or partly silent, thus perturbing the progression of traveling waves across perilesional areas. Secondly, we focus on a simplified model based on the current literature in the field and describe cortical traveling wave dynamics and their modulation. This model uses a biophysically realistic integro-differential equation describing spatially distributed and synaptically coupled neural networks producing traveling wave solutions. The model is used to calculate wave parameters (speed, amplitude and/or frequency) and to guide the reconstruction of the perturbed wave. A stimulation term is included in the model to restore wave propagation to a reasonably good level. Thirdly, we examine various issues related to the implementation model-guided neuromodulation in the treatment of post-stroke aphasia given that closed-loop invasive brain stimulation studies have recently produced encouraging results. Finally, we suggest that modulating traveling waves by acting selectively and dynamically across space and time to facilitate wave propagation is a promising therapeutic strategy especially at a time when a new generation of closed-loop cortical stimulation systems is about to arrive on the market.
本文的目的是整合不同的研究领域，包括脑行波、脑神经调节、神经场建模和中风后语言障碍，以探索实施模型引导的皮层神经调节治疗中风后失语症的机会。据世界卫生组织统计，中风是全球第二大死因和第三大致残原因。在缺血性中风中，没有足够的血液供应为大脑的某些部位提供足够的氧气和营养，而在出血性中风中，封闭的颅腔内会出血。本文重点关注缺血性中风。我们首先回顾了在健康受试者以及脑部疾病患者中自发出现或由外部刺激触发的行波的累积观察结果。我们研究了这些波的假定功能，并关注当脑语言网络变得碎片化和/或部分沉默，从而扰乱跨病变周围区域的行波进展时观察到的中风后失语症。其次，我们基于该领域的现有文献重点介绍一个简化模型，并描述皮层行波动力学及其调制。该模型使用一个生物物理上逼真的积分 - 微分方程来描述产生行波解的空间分布和突触耦合神经网络。该模型用于计算波参数（速度、幅度和/或频率）并指导对受干扰波的重建。模型中包含一个刺激项，以将波传播恢复到合理的良好水平。第三，鉴于最近闭环侵入性脑刺激研究取得了令人鼓舞的结果，我们研究了在中风后失语症治疗中实施模型引导神经调节的各种问题。最后，我们认为通过在空间和时间上选择性地、动态地采取行动来调节行波以促进波传播是一种有前景的治疗策略，尤其是在新一代闭环皮层刺激系统即将上市之际。
