Arnal-Real Cristian, Mahmoudzadeh Mahdi, Manoochehri Mana, Nourhashemi Mina, Wallois Fabrice
Inserm U1105, GRAMFC, CURS, Université de Picardie Jules Verne, Amiens, France.
Front Neurol. 2021 Feb 12;12:596926. doi: 10.3389/fneur.2021.596926. eCollection 2021.
Interictal spikes (IISs) may result from a disturbance of the intimate functional balance between various neuronal (synaptic and non-synaptic), vascular, and metabolic compartments. To better characterize the complex interactions within these compartments at different scales we developed a simultaneous multimodal-multiscale approach and measure their activity around the time of the IIS. We performed such measurements in an epileptic rat model ( = 43). We thus evaluated (1) synaptic dynamics by combining electrocorticography and multiunit activity recording in the time and time-frequency domain, (2) non-synaptic dynamics by recording modifications in light scattering induced by changes in the membrane configuration related to cell activity using the fast optical signal, and (3) vascular dynamics using functional near-infrared spectroscopy and, independently but simultaneously to the electrocorticography, the changes in cerebral blood flow using diffuse correlation spectroscopy. The first observed alterations in the measured signals occurred in the hemodynamic compartments a few seconds before the peak of the IIS. These hemodynamic changes were followed by changes in coherence and then synchronization between the deep and superficial neural networks in the 1 s preceding the IIS peaks. Finally, changes in light scattering before the epileptic spikes suggest a change in membrane configuration before the IIS. Our multimodal, multiscale approach highlights the complexity of (1) interactions between the various neuronal, vascular, and extracellular compartments, (2) neural interactions between various layers, (3) the synaptic mechanisms (coherence and synchronization), and (4) non-synaptic mechanisms that take place in the neuronal network around the time of the IISs in a very specific cerebral hemodynamic environment.
发作间期棘波（IISs）可能源于各种神经元（突触和非突触）、血管及代谢成分之间紧密的功能平衡紊乱。为了更好地表征这些成分在不同尺度下的复杂相互作用，我们开发了一种同步多模态 - 多尺度方法，并在IISs发生时测量它们的活动。我们在癫痫大鼠模型（n = 43）中进行了此类测量。因此，我们评估了：（1）通过在时域和时频域结合皮层脑电图和多单位活动记录来评估突触动力学；（2）通过使用快速光信号记录与细胞活动相关的膜构型变化引起的光散射改变来评估非突触动力学；（3）使用功能近红外光谱法评估血管动力学，并独立且同时于皮层脑电图测量使用扩散相关光谱法测量的脑血流量变化。在IISs峰值前几秒，首先在血流动力学成分中观察到测量信号的改变。这些血流动力学变化之后是相干性的变化，然后是IISs峰值前1秒内深部和浅部神经网络之间的同步。最后，癫痫棘波前的光散射变化表明IISs前膜构型发生了变化。我们的多模态、多尺度方法突出了以下方面的复杂性：（1）各种神经元、血管和细胞外成分之间的相互作用；（2）各层之间的神经相互作用；（3）突触机制（相干性和同步性）；（4）在非常特定的脑血流动力学环境中，IISs发生时神经网络中发生的非突触机制。
