National Vision Research Institute, Australian College of Optometry, Carlton, VIC 3053, Australia.
Department of Biomedical Engineering, University of Melbourne, Parkville, VIC 3010, Australia.
J Neural Eng. 2022 Aug 18;19(4). doi: 10.1088/1741-2552/ac861f.
Retinal prostheses have had limited success in vision restoration through electrical stimulation of surviving retinal ganglion cells (RGCs) in the degenerated retina. This is partly due to non-preferential stimulation of all RGCs near a single stimulating electrode, which include cells that conflict in their response properties and their contribution to visiual processing. Our study proposes a stimulation strategy to preferentially stimulate individual RGCs based on their temporal electrical receptive fields (tERFs).We recorded the responses of RGCs using whole-cell patch clamping and demonstrated the stimulation strategy, first using intracellular stimulation, then via extracellular stimulation.. We successfully reconstructed the tERFs according to the RGC response to Gaussian white noise current stimulation. The characteristics of the tERFs were extracted and compared based on the morphological and light response types of the cells. By re-delivering stimulation trains that were composed of the tERFs obtained from different cells, we could preferentially stimulate individual RGCs as the cells showed lower activation thresholds to their own tERFs.This proposed stimulation strategy implemented in the next generation of recording and stimulating retinal prostheses may improve the quality of artificial vision.
视网膜假体通过对退化视网膜中存活的视网膜神经节细胞（RGC）进行电刺激，在视力恢复方面取得了有限的成功。这在一定程度上是由于对单个刺激电极附近的所有 RGC 进行非优先刺激，其中包括在反应特性和对视觉处理的贡献上存在冲突的细胞。我们的研究提出了一种基于 RGC 时间电感受野（tERF）的刺激策略，以优先刺激单个 RGC。我们使用全细胞膜片钳记录了 RGC 的反应，并首先使用细胞内刺激，然后通过细胞外刺激演示了该刺激策略。我们根据 RGC 对高斯白噪声电流刺激的反应成功重建了 tERFs。根据细胞的形态和光反应类型提取和比较了 tERFs 的特征。通过重新传递由来自不同细胞的 tERFs 组成的刺激序列，我们可以优先刺激单个 RGC，因为细胞对自身的 tERFs 表现出较低的激活阈值。该刺激策略在下一代记录和刺激视网膜假体中实施，可能会提高人工视觉的质量。
