Activation zones in cat visual cortex evoked by electrical retina stimulation
Activation zones in cat visual cortex evoked by electrical retina stimulation
复制标题
视网膜电刺激诱发猫视觉皮层的激活区
DOI：
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
R. Eckhorn
中科院分区：
文献类型：
--
作者：
T. Schanze;M. Wilms;M. Eger;L. Hesse;R. Eckhorn
抽象的
背景。用于恢复因光感受器丧失而失明的患者的简单基本视觉感知的视网膜植入物需要优化刺激参数以获得高时空分辨率。我们在半慢性准备的猫身上开发了有效的低功率视网膜外刺激和皮质内记录。
方法。通过小的巩膜切口插入可单独驱动的纤维电极并定位在中央区域。通过角膜切口插入聚酰亚胺-铂膜电极，并通过将全氟化碳液体滴在内界膜上进行固定。对于电刺激，我们使用持续时间为 100–400 µs、幅度为 1 至 100 µA 的短电荷平衡电流脉冲。在刺激过程中，我们记录了区域 17 和区域 18 的多个单细胞和群体活动。记录以数字方式存储。离线分析刺激-反应关系，包括反应强度、皮质激活区、信息传输和电感受野。
结果。我们发现纤维电极和聚酰亚胺铂薄膜电极与视网膜紧密机械接触时的低阈值激活。双极电荷平衡脉冲的视网膜刺激导致皮层激活区对应于旁中心位置的 1-5° 视角，具体取决于视网膜刺激点的偏心率。视网膜皮质转换信息分析显示每个电极 20-30 位/秒，对应于 10-15 个四级图片/秒。电感受野的视角为 1-3°。
结论。视网膜植入物似乎可以实现粗略的视觉运动协调和导航。
Abstract
Background. A retina implant for restoring simple basic visual perception in patients who are blind due to photoreceptor loss requires optimisation of stimulation parameters for obtaining high spatio-temporal resolution. We developed effective low-power epi-retinal stimulation and intracortical recording in semichronically prepared cats.
Methods. Individually driveable fibre electrodes were inserted through a small scleral incision and positioned at the area centralis. Polyimide–platinum film electrodes were inserted via a corneal incision and fixed by instillation of perfluorocarbon liquid on the internal limiting membrane. For electrical stimulation we used short charge-balanced current impulses of 100–400 µs duration and amplitudes ranging from 1 to 100 µA. During stimulation we recorded multiple single-cell and population activities from areas 17 and 18. Recordings were stored digitally. Stimulus–response relations including response strength, cortical activation zones, information transmission, and electrical receptive fields were analysed off-line.
Results. We found low-threshold activations with fibre electrodes and polyimide–platinum film electrodes in close mechanical contact to the retina. Retinal stimulation with bipolar charge-balanced impulses resulted in cortical activation zones corresponding to 1–5° visual angle at paracentral locations dependent on the eccentricity of the retinal stimulation point. Retino-cortical transinformation analysis revealed 20–30 bits/s per electrode, corresponding to 10–15 four-level pictures/s. Electrical receptive fields had sizes of 1–3° visual angle.
Conclusions. Coarse visuomotor coordination and navigation seems possible with retina implants.
影响因子：
1.8
作者：
Zrenner, E;Stett, A;Haemmerle, H
通讯作者：
Haemmerle, H