Translational Neuroscience Division, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA.
Department of Psychiatry, New York University School of Medicine, New York, NY, USA.
Brain Topogr. 2022 Jan;35(1):162-168. doi: 10.1007/s10548-021-00853-1. Epub 2021 Jun 4.
Traveling waves appear in various signals that measure neuronal activity. Some signals measured in animals have singles-cell resolution and directly point to neuronal activity. In those cases, activation of distributed neurons forms a wave front, and the front propagates across the cortical surface. Other signals are variants of neuroelectric potentials, i.e. electroencephalography, electrocorticography and field potentials. Instead of having fine spatial resolution, these signals reflect the activity of neuronal populations via volume conduction (VC). Sources of traveling waves in neuroelectric potentials have not been well addressed so far. As animal studies show propagating activation of neurons that spread in measured areas, it is often considered that neuronal activations during scalp waves have similar trajectories of activation, spreading like scalp waves. However, traveling waves on the scalp differ from those found directly on the cortical surface in several dimensions: traveling velocity, traveling distance and areal size occupied by single polarity. We describe that the simplest sources can produce scalp waves with perceived spatial dimensions which are actually a magnification of neuronal activity emanating from local sources due to VC. This viewpoint is not a rigorous proof of our magnification concept. However, we suggest the possibility that the actual dimensions of neuronal activity producing traveling waves is not as large as the dimension of the traveling waves.
在测量神经元活动的各种信号中都会出现行波。一些在动物身上测量到的信号具有单细胞分辨率，并且直接指向神经元活动。在这些情况下，分布式神经元的激活形成波前，波前在皮质表面传播。其他信号是神经电潜力的变体，即脑电图、皮质电图和场电位。这些信号不是通过体积传导（VC）来反映神经元群体的活动，而是具有精细的空间分辨率。到目前为止，神经电潜力中行波的源还没有得到很好的解决。由于动物研究表明神经元的激活在测量区域中传播，因此人们通常认为头皮波期间的神经元激活具有相似的激活轨迹，像头皮波一样传播。然而，头皮上的行波与直接在皮质表面上发现的行波在几个方面有所不同：传播速度、传播距离和单个极性占据的面积。我们描述了最简单的源可以产生具有感知空间维度的头皮波，这些维度实际上是由于 VC 而从局部源发出的神经元活动的放大。这种观点不是我们放大概念的严格证明。然而，我们提出了这样一种可能性，即产生行波的神经元活动的实际维度并不像行波的维度那么大。
