Determinants of Signal Characteristics in a Retinal Network: Contribution of Local Field Potentials and Spike Trains.

视网膜网络中信号特征的决定因素：局部场电位和尖峰序列的贡献。

• 批准号: RGPIN-2015-04250
• 负责人: Tremblay, Francois
• 金额: $ 1.75万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=612855
• 关键词: Determinants; Signal; Characteristics; Retinal; Network

The teamwork research taking place in my lab share the common objective of a better comprehension of how the neural activity of the various cell populations of the retina translates a visual stimulus into a neural code that can be understood by the brain. We have been using for many years the electroretinogram (ERG), a composite signal collected non-invasively at the surface of the cornea, to decipher the relative contribution of different cell population. More recently, we have gained expertise in the multi electrode array (MEA), a technology that allows the ex-vivo (isolated retina) recording of both the ERG-like signal and the spiking activity of the ganglion cells, the population giving rise to the efferent message of the retina.  Using the classical pharmacopeia of neurotransmitter a-/antagonists, we have documented many types of interactions occurring in the composite ERG signal, particularly at the level of the RGCs and the bipolar cells, two major contributors to the ERG signal. More recently, we have developed a innovative immunological method to selectively target specific isoforms of the Voltage-Gated Sodium Channels. This novel method shall allow us to decipher the role of dendritic integration and spike generation in the overall retinal processing. It is our intention in the next few years to capitalize on this new technique to further our knowledge on how integration takes place in response to diffuse changes in light intensities (serial integration) and how various parts of a visual scene interplay (lateral integration) to form a meaningful efferent message. We will also start investigating how the simple integrative plexus that constitutes the retina is capable of processing the astronomical amount of information generated by a visual scene. For that purpose, we will analyze the retinal activity captured in parallel by the 64 recording channels of the MEA and investigate the data by applying energy-saving processes algorithms such as transfer entropy, coherence estimation or dimension reduction and population activity time-course to the neural code generated by complex stimuli.

在我的实验室里进行的团队合作研究都有一个共同的目标，那就是更好地理解视网膜不同细胞群的神经活动如何将视觉刺激转化为大脑可以理解的神经代码。多年来，我们一直使用视网膜电信号(ERG)，这是一种在角膜表面非侵入性收集的复合信号，用于破译不同细胞群的相对贡献。最近，我们在多电极阵列(MEA)方面获得了专业知识，这项技术允许体外(独立视网膜)记录ERG样信号和神经节细胞的尖峰活动，神经节细胞的群体产生视网膜的传出信息。通过使用神经递质α-/拮抗剂的经典药典，我们已经记录了复合ERG信号中发生的多种类型的相互作用，特别是在RGC和双极细胞水平上，这两个细胞是ERG信号的两个主要贡献者。最近，我们开发了一种创新的免疫学方法来选择性地靶向电压门控钠通道的特定亚型。这一新的方法将使我们能够破译树突整合和棘波产生在整个视网膜加工中的作用。我们打算在未来几年利用这项新技术，进一步了解整合是如何响应光强度的漫射变化而发生的(串联整合)，以及视觉场景的不同部分如何相互作用(横向整合)来形成有意义的传出信息。我们还将开始研究组成视网膜的简单整合神经丛如何能够处理由视觉场景产生的天文数字信息量。为此，我们将分析MEA的记录通道并行捕获的视网膜活动，并将节能过程算法(如传递熵、相干估计或降维和群体活动时间过程)应用于复杂刺激产生的神经代码来调查数据。