Neural mechanisms that detect defocus in the retina

检测视网膜散焦的神经机制

• 批准号: 10700107
• 负责人: William Rowland Taylor
• 金额: $ 20.06万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-30 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10700107
• 关键词: Acute; Amacrine Cells; Animals; Area; Calcium; Cells; Characteristics; Cone; Cues; Development; Electrophysiology (science); Elements; Eye; Frequencies; Functional Imaging; Functional disorder; Future; Goals; Growth; Hour; Image; In Situ; Lead; Length; Light; Maps; Measures; Methods; Monitor; Morphology; Myopia; Neurobiology; Neurons; Optics; Pathway interactions; Pattern; Photic Stimulation; Preparation; Prevalence; Process; Property; Research; Retina; Role; Sensory; Signal Transduction; Stains; Stimulus; Synapses; Testing; Vision; Visual; Visual Accommodation; Visual System; Whole-Cell Recordings; Work; candidate identification; design; detection platform; detector; emmetropization; extracellular; ganglion cell; insight; interest; lens; movie; multi-photon; neural; neuromechanism; neuronal cell body; neurotransmission; receptive field; response; retinal imaging; retinal neuron; two-photon; visual stimulus; voltage clamp

PROJECT SUMMARY A sharp retinal image is essential for accurately encoding the visual world. The focal length of the eyes' optics can be adjusted within a fraction of a second to bring object of interest into sharp focus, a process called “accommodation”. On longer timescales, hours to months, a sharp retinal image is made possible when the axial length of the eye grows to match the refractive power of the optics, a process called “emmetropization”. In order to respond appropriately, accommodation and emmetropization require the retina to detect the sign and magnitude of image defocus. It is well established that the major optical cue that signals the sign of defocus is longitudinal chromatic aberration (LCA). LCA is due to the stronger refraction of short than long wavelength light. The identity of the neurons in the retina that detect LCA signals, and how they relay the signals to the down-stream mechanisms that control eye growth and accommodation, remains one of the great outstanding puzzles in sensory neurobiology. This proposal aims to identify the retinal neurons that respond to LCA. We will use multi-photon calcium imaging to simultaneously measure responses from tens to hundreds of neurons within an area of retina under photopic adaptation levels. Patterned, chromatic images will be used to identify candidate defocus neurons. The somas of the neurons will then be targeted for single-cell whole-cell recordings to measure in detail the receptive field properties and to recover the morphology. We will also measure responses to natural scenes rendered with and without LCA calculated for the optics of the eye. Identification LCA-sensitive neurons will lay the groundwork for future studies aimed at determining how these retinal neurons ultimately control accommodation and emmetropization. These insights may also provide clues as to the origin of the mysterious, continuing increase in the prevalence of myopia and perhaps lead to development of mitigative strategies.

项目摘要 清晰的视网膜图像对于准确编码视觉世界至关重要。焦点 眼睛的长度可以在一秒钟内调节，以带来 感兴趣的焦点，这是一个称为“住宿”的过程。在更长的时间尺度上，小时 到几个月，当眼睛的轴向长度生长时，使视网膜图像成为可能 为了匹配光学的折射率，一个称为“弹药化”的过程。为了 为了适当响应，住宿和弹性化需要视网膜 检测图像散焦的符号和大小。众所周知，专业 信号散焦的光学提示是纵向色差（LCA）。 LCA是由于比长波长光更强的折射。的身份 视网膜中检测到LCA信号的神经元，以及它们如何将信号传递到 控制眼睛生长和适应性的下游机制仍然是 感官神经生物学中的杰出难题。该建议旨在确定 对LCA反应的视网膜神经元。我们将使用多光子钙成像 类似地测量的反应从数十到数百个神经元的区域内 视网膜在光波适应水平下。图案化的色彩图像将用于 识别候选神经元。然后，神经元的躯体将被靶向 单细胞全细胞记录，以详细测量接受场特性和TO 恢复形态。我们还将衡量对呈现自然场景的反应 并且没有针对眼睛光学计算的LCA。鉴定LCA敏感神经元 将为未来的研究奠定基础，旨在确定这些视网膜 神经元最终控制适应和弹性化。这些见解可能 还提供有关神秘的起源的线索 近视，也许会发展缓解策略。