Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China.
University of Chinese Academy of Sciences, Beijing, China.
PLoS One. 2021 Mar 11;16(3):e0246547. doi: 10.1371/journal.pone.0246547. eCollection 2021.
Retinal prostheses can restore the basic visual function of patients with retinal degeneration, which relies on effective electrical stimulation to evoke the physiological activities of retinal ganglion cells (RGCs). Current electrical stimulation strategies have defects such as unstable effects and insufficient stimulation positions, therefore, it is crucial to determine the optimal pulse parameters for precise and safe electrical stimulation. Biphasic voltages (cathode-first) with a pulse width of 25 ms and different amplitudes were used to ex vivo stimulate RGCs of three wild-type (WT) mice using a commercial microelectrode array (MEA) recording system. An algorithm is developed to automatically realize both spike-sorting and electrical response identification for the spike signals recorded. Measured from three WT mouse retinas, the total numbers of RGC units and responsive RGC units were 1193 and 151, respectively. In addition, the optimal pulse amplitude range for electrical stimulation was determined to be 0.43 V-1.3 V. The processing results of the automatic algorithm we proposed shows high consistency with those using traditional manual processing. We anticipate the new algorithm can not only speed up the elaborate electrophysiological data processing, but also optimize pulse parameters for the electrical stimulation strategy of neural prostheses.
视网膜假体可以恢复视网膜变性患者的基本视觉功能，这依赖于有效的电刺激来诱发视网膜神经节细胞（RGCs）的生理活动。目前的电刺激策略存在效果不稳定和刺激位置不足等缺陷，因此，确定精确和安全的电刺激的最佳脉冲参数至关重要。使用商业微电极阵列（MEA）记录系统，使用脉宽为 25ms 的双相电压（阴极先）和不同幅度对三只野生型（WT）小鼠的 RGC 进行离体刺激。开发了一种算法，用于自动实现对记录的尖峰信号的尖峰分类和电响应识别。从三只 WT 小鼠视网膜测量到的 RGC 总数和响应 RGC 数分别为 1193 和 151。此外，确定了电刺激的最佳脉冲幅度范围为 0.43V-1.3V。我们提出的自动算法的处理结果与传统手动处理的结果高度一致。我们预计新算法不仅可以加快精细电生理数据的处理速度，还可以优化神经假体电刺激策略的脉冲参数。
