Increasing Electrical Stimulation Efficacy in Degenerated Retina: Stimulus Waveform Design in a Multiscale Computational Model
Increasing Electrical Stimulation Efficacy in Degenerated Retina: Stimulus Waveform Design in a Multiscale Computational Model
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DOI：
10.1109/tnsre.2018.2832055
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发表时间：
2018-06-01
影响因子：
4.9
通讯作者：
Lazzi, Gianluca
中科院分区：
文献类型：
--
作者：
Loizos, Kyle;Marc, Robert;Lazzi, Gianluca
提出了一种视网膜电刺激的计算模型，用于研究修复装置中用于恢复因视网膜退行性疾病而丧失的部分视力的电流波形。该模型框架结合了一个基于连接体的神经网络模型，其特征在于准确的形态和突触特性与本体组织和假体电子学的导纳方法模型。在这个模型中，视网膜在计算上“退化”，考虑到疾病早期发生的细胞死亡和解剖学变化，以及在整个神经变性过程中发生的神经行为改变，并且可能干扰目前恢复视力的尝试。一个由此产生的分析的刺激范围和阈值的视网膜内的神经节细胞是健康的或在开始阶段的退化是目前使用的刺激波形，并提出了一个不对称的双相电流刺激，用于抑制自发放电，以允许增加控制神经节细胞放电模式在退化的视网膜。结果表明，视网膜神经节细胞的刺激阈值在视网膜变性的开始阶段没有明显的变化。此外，所提出的非对称波形的模拟显示了通过电刺激增强对神经节细胞放电的控制的能力。
A computational model of electrical stimulation of the retina is proposed for investigating current waveforms used in prosthetic devices for restoring partial vision lost to retinal degenerative diseases. The model framework combines a connectome-based neural network model characterized by accurate morphological and synaptic properties with an admittance method model of bulk tissue and prosthetic electronics. In this model, the retina was computationally "degenerated," considering cellular death and anatomical changes that occur early in disease, as well as altered neural behavior that develops throughout the neurodegeneration and is likely interfering with current attempts at restoring vision. A resulting analysis of stimulation range and threshold of ON ganglion cells within the retina that are either healthy or in beginning stages of degeneration is presented for currently used stimulation waveforms, and an asymmetric biphasic current stimulation for subduing spontaneous firing to allow increased control over ganglion cell firing patterns in degenerated retina is proposed. Results show that stimulation thresholds of retinal ganglion cells do not notably vary after beginning stages of retina degeneration. In addition, simulation of proposed asymmetric waveforms showed the ability to enhance the control of ganglion cell firing via electrical stimulation.