Prediction of cortical responses to simultaneous electrical stimulation of the retina
Prediction of cortical responses to simultaneous electrical stimulation of the retina
复制标题
DOI：
10.1088/1741-2560/14/1/016006
复制
发表时间：
2017-02-01
影响因子：
4
通讯作者：
Meffin, Hamish
中科院分区：
文献类型：
--
作者：
Halupka, Kerry J.;Shivdasani, Mohit N.;Meffin, Hamish
Objective.与交错的单电极刺激相比，多个电极的同时电刺激已经显示出使视网膜假体引起的反应多样化的前景。然而，电极之间的相互作用的影响还没有得到很好的理解，同时刺激的临床试验产生了不一致的结果。我们研究了多电极刺激视网膜的影响，通过开发一个模型的皮层反应视网膜刺激。Approach.电刺激组成的时间稀疏，双相电流脉冲，从一个二维高斯分布采样的幅度，同时提供给视网膜通过42通道电极阵列植入麻醉猫脉络膜上腔。使用穿透微电极阵列记录视觉皮层活动。这些数据被用来确定一个线性-非线性模型的皮质反应视网膜刺激。通过预测对非白色图案刺激的反应来测试模型的泛化能力。主要结果。该模型准确地预测了两个皮层活动措施：多单位神经反应和诱发电位反应白色噪声刺激。该模型还提供了有关电感受野的信息，包括每个刺激电极对每个记录部位的相对影响。意义我们已经证明了一个简单的模型，准确地描述了皮质的反应，同时刺激脉络膜上视网膜假体。总的来说，我们的研究结果表明，同时多电极刺激视网膜的皮层反应是可重复的和可预测的，同时刺激过程中电极之间的相互作用主要是线性的。该模型显示出确定最佳刺激范例的希望，以利用电极之间的相互作用来塑造神经活动，从而改善视网膜假体患者的结果。
Objective. Simultaneous electrical stimulation of multiple electrodes has shown promise in diversifying the responses that can be elicited by retinal prostheses compared to interleaved single electrode stimulation. However, the effects of interactions between electrodes are not well understood and clinical trials with simultaneous stimulation have produced inconsistent results. We investigated the effects of multiple electrode stimulation of the retina by developing a model of cortical responses to retinal stimulation. Approach. Electrical stimuli consisting of temporally sparse, biphasic current pulses, with amplitudes sampled from a bi-dimensional Gaussian distribution, were simultaneously delivered to the retina across a 42-channel electrode array implanted in the suprachoroidal space of anesthetized cats. Visual cortex activity was recorded using penetrating microelectrode arrays. These data were used to identify a linear-nonlinear model of cortical responses to retinal stimulation. The ability of the model to generalize was tested by predicting responses to non-white patterned stimuli. Main results. The model accurately predicted two cortical activity measures: multi-unit neural responses and evoked potential responses to white noise stimuli. The model also provides information about electrical receptive fields, including the relative effects of each stimulating electrode on every recording site. Significance. We have demonstrated a simple model that accurately describes cortical responses to simultaneous stimulation of a suprachoroidal retinal prosthesis. Overall, our results demonstrate that cortical responses to simultaneous multi-electrode stimulation of the retina are repeatable and predictable, and that interactions between electrodes during simultaneous stimulation are predominantly linear. The model shows promise for determining optimal stimulation paradigms for exploiting interactions between electrodes to shape neural activity, thereby improving outcomes for patients with retinal prostheses.