Optimality of a Sensory Receptor Array

感觉感受器阵列的最优性

• 批准号: 0515290
• 负责人: Tomas Gedeon
• 金额: $ 59.96万
• 依托单位: Montana State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0515290&HistoricalAwards=false
• 关键词: Optimality; Sensory; Receptor; Array

An implicit hypothesis underlying much recent research in neuroscience and neuroethology is that sensory systems have evolved, through natural selection, toward optimal functional performance and/or energetic efficiency. However, it has proven extremely difficult to derive precise definitions for functional optimality and efficiency, and even more difficult to determine the nature and relative importance of different factors that might be constraining this process of optimization. A multidisciplinary group of researchers lead by Dr. Gedeon will develop a theoretical framework for defining and assessing optimality of one specific sensory system and are also carrying out experiments to assess its optimality and efficiency. The system they are studying is the cercal sensory system of the cricket, Acheta domesticus. This system functions as a low-frequency, near-field extension of the animal's auditory system, and mediates the detection, localization and identification of signals generated by predators, mates and competitors. The sense organ for this system consists of a pair of antenna-like 'cerci' at the rear of the cricket's body, each of which is covered with approximately 1000 mechanosensory hairs. Each of these hairs is attached to a single nerve cell. The group's working hypothesis is that the biomechanical and neurophysiological characteristics of these receptor organs are optimized for the sensory processing operations they mediate. The researchers will determine the extent and nature of optimization in the array of mechanosensory hairs and receptors, and will also identify specific constraints under which the optimization has taken place. For example, they will determine whether the physical structures of the hairs are matched to behaviorally relevant air-current signals and also determine if the global configuration of the ensemble of hairs on the two cerci reflects optimization with respect to sensitivity, robustness to noise, and/or to the detection of specific types of signals having particular behavioral importance, such as those from predators. They will also characterize constraints on optimization related to biomechanics, resource utilization, and efficiency of subsequent processing operations. These aims are being achieved through a combination of mathematical analysis, computer simulation, quantitative morphometric analysis of the sensory structures, and neurophysiological experiments. Graduate students in Mathematics and Neuroscience will be involved in the project, and an interdisciplinary graduate-level course is being developed that focuses on optimality in neural systems. Further, in collaboration with the American Indian Research Opportunities program at Montana State University, Native American students at the undergraduate and pre-college levels will carry out many of the experiments and associated data analysis.

最近在神经科学和神经行为学研究中有一个隐含的假设，即感觉系统已经通过自然选择进化到最佳功能表现和/或能量效率。然而，事实证明，要得出函数最优性和效率的精确定义是极其困难的，要确定可能限制这一优化过程的不同因素的性质和相对重要性就更加困难了。一个由Gedeon博士领导的多学科研究小组将开发一个理论框架来定义和评估一个特定感官系统的最佳性，并正在进行实验来评估其最佳性和效率。他们正在研究的系统是蟋蟀（Acheta domesticus）的神经感觉系统。该系统的功能是动物听觉系统的低频近场延伸，并介导对捕食者、配偶和竞争对手产生的信号的检测、定位和识别。这个系统的感觉器官由蟋蟀身体后部的一对天线状的“尾毛”组成，每个尾毛上都覆盖着大约1000根机械感测毛。每根毛发都附着在一个神经细胞上。该小组的工作假设是，这些受体器官的生物力学和神经生理学特征对它们介导的感觉处理操作进行了优化。研究人员将确定机械感觉毛发和受体阵列优化的程度和性质，并将确定优化发生的具体限制条件。例如，他们将确定毛发的物理结构是否与行为相关的气流信号相匹配，并确定两个cerci上毛发集合的整体结构是否反映了灵敏度、对噪声的鲁棒性和/或对具有特定行为重要性的特定类型信号的检测的优化，例如来自捕食者的信号。他们还将描述与生物力学、资源利用和后续处理操作效率相关的优化限制。这些目标是通过结合数学分析、计算机模拟、感官结构的定量形态分析和神经生理学实验来实现的。数学和神经科学的研究生将参与该项目，并且正在开发一门跨学科的研究生课程，重点是神经系统的最优性。此外，与蒙大拿州立大学的美国印第安人研究机会项目合作，美国土著学生将在本科和大学预科阶段进行许多实验和相关数据分析。