复杂的光遗传学和电刺激视网膜团细胞用于人工视觉
William C Kwan1, Emma K Brunton2, Toon Goris3
1Department of Biomedical Engineering, University of Melbourne, Parkville, VIC, Australia; Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia.
Brain stimulation
|December 24, 2025
概括
一种新的光电混合刺激策略通过提高空间分辨率和响应可靠性来显著增强视觉假肢. 这种方法降低了激活值和传播,为与神经组织接口的生物设备提供了更好的控制.
科学领域:
- 神经科学是一个神经科学.
- 生物医学工程 生物医学工程
- 眼科医生 眼科 眼科
背景情况:
- 数以百万计的人患有视网膜疾病的视力损伤,如视网膜色素炎和黄斑变性.
- 目前使用电刺激的视网膜假肢由于电传播,视力质量有限.
- 光遗传学方法提供精度,但与电刺激相比,其时间性质较差.
研究的目的:
- 开发和评估一种光电混合刺激策略,以改善视觉假肢.
- 评估混合刺激在正常视网膜和患病视网膜中的有效性.
- 将混合刺激与纯电和纯光遗传方法进行比较.
主要方法:
- 开发了一种光电混合刺激方法.
- 在正常视力小鼠和皇家外科医生学院的老鼠中测试了该策略,这些老鼠具有退化的视网膜.
- 使用全细胞补丁记录和GCaMP7s生物传感器进行响应测量.
主要成果:
- 混合刺激可以将电气和光遗传激活值降低高达50%.
- 与单一方法相比,唤起了明显更高的发射频率 (高达2倍).
- 在患病的视网膜中改善空间分辨率和减少激活传播.
结论:
- 混合刺激提供了比单独的电刺激更局部的神经激活.
- 提高响应可靠性,降低光学强度值,相比光学纯粹的方法.
- 在未来的视觉假肢和神经调节器件中,有可能提高分辨率,刷新率和控制.
相关概念视频
01:32The Retina
The retina is a layer of nervous tissue at the back of the eye that transduces light into neural signals. This process, called phototransduction, is carried out by rod and cone photoreceptor cells in the back of the retina.
01:24Vision
Vision is the result of light being detected and transduced into neural signals by the retina of the eye. This information is then further analyzed and interpreted by the brain. First, light enters the front of the eye and is focused by the cornea and lens onto the retina—a thin sheet of neural tissue lining the back of the eye. Because of refraction through the convex lens of the eye, images are projected onto the retina upside-down and reversed.
01:20Anatomy of the Eyeball
The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle layer, the vascular tunic,...
01:22Photoreceptors and Visual Pathways
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01:26Visual System
Light enters the eye through the cornea, a transparent, dome-shaped surface covering the surface of the eyeball that helps to direct and focus incoming light. This light is then channeled toward the pupil, an adjustable opening whose size is controlled by the iris. The iris, a pigmented muscle, regulates the amount of light entering the eye by contracting or dilating the pupil, thereby ensuring optimal light levels for clear vision.
Once through the pupil, the light passes through the lens, a...
Once through the pupil, the light passes through the lens, a...