Integration of sleep/wake network models across multiple temporal and spatial sca

跨多个时间和空间尺度的睡眠/唤醒网络模型的集成

• 批准号: 8568069
• 负责人: Andrew John Phillips
• 金额: $ 8.88万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-05 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8568069
• 关键词: Adenosine A1 Receptor; Adult; Affect; Area; Arousal; Behavior; Behavioral; Biological Models; Biological Neural Networks; Biometry; Brain Stem; Cell Nucleus; Chronic; Circadian Rhythms; Data; Development; Development Plans; Disease; Educational process of instructing; Environment; Equation; Functional disorder; Goals; Grant; Guidelines; Head; Health; Heterogeneity; Homeostasis; Hospitals; Hour; Human; Hypothalamic structure; Inpatients; Lead; Leadership; Learning; Length; Link; Location; Mammals; Medicine; Mentors; Mentorship; Modeling; Narcolepsy; Neurons; Noise; Organism; Output; Pathology; Performance; Phenotype; Physiological; Physiology; Population; Process; Property; Protocols documentation; Publications; Purinergic P1 Receptors; Rattus; Research; Research Personnel; Rest; Schedule; Sleep; Sleep Deprivation; Sleep Disorders; Sleep Fragmentations; Sleep Wake Cycle; Statistical Distributions; Structure; System; Testing; Theoretical model; Time; Training; Up-Regulation; Woman; Work; age effect; base; career; career development; circadian pacemaker; computational neuroscience; experience; human data; improved; in vivo; innovation; mathematical model; medical schools; millisecond; models and simulation; network models; predictive modeling; receptor; receptor density; relating to nervous system; research and development; research study; response; skills; suprachiasmatic nucleus; theories; therapy design; voltage

DESCRIPTION (provided by applicant): Sleep in mammals is regulated on multiple temporal and spatial scales. Recent experimental findings have revealed the importance of neuronal sleep/wake control systems in the brainstem and hypothalamus operating on the millisecond timescale that affect the organism's behavior on the hour timescale. These systems include mutually inhibitory sleep-promoting and wake-promoting nuclei that together comprise the "sleep/wake switch". It has been proposed that inputs to this switch, including the output of the master circadian pacemaker located in the suprachiasmatic nucleus (SCN) of the mammalian hypothalamus, and the sleep homeostatic process produce the observed sleep/wake cycles. This sleep/wake switch theory has become the basis for understanding some sleep disorders (e.g., narcolepsy) and the effects of aging on sleep. In the last 6 years, several mathematical models of this system have been proposed at different spatial scales, including neural mass (neuronal population level) and neuronal network (single neuron level) models. These models have been used for relating behavioral phenotypes to underlying physiology and testing assumptions about our theoretical models of sleep. However, the existing models are limited in their spatial and temporal scales, making it impossible to study multi-scale interactions, e.g., interactions between chronic sleep restriction (long timescale) and sleep fragmentation (short timescale). Moreover, model assumptions about the spatial and temporal properties of the underlying physiology have not been tested. Mathematical models have proven important in defining normal and abnormal physiological relationships, and testing potential treatments in many health- related areas. Therefore, integrating models of sleep across spatial and temporal scales will improve understanding of sleep physiology and pathophysiology, and be instrumental in designing interventions. To achieve integration of sleep models across spatial and temporal scales, we will pursue four linked goals. (i) To determine the conditions under which neural mass models and neuronal network models of the sleep/wake switch predict the same dynamics. We will develop a neuronal network version of our existing neural mass model and test the effects of parameter heterogeneity, network size, and network connectivity. (ii) To test the hypothesis that sleep is inherently fragmented on short timescales due to noisy input to the sleep/wake switch. To achieve this, we will incorporate noisy inputs into both neural mass and neuronal network models and compare predictions to human data from an inpatient protocol. (iii) To test the hypothesis that chronic sleep restriction effects on sleep and performance are due to an interaction between the sleep/wake switch and long timescale dynamics of adenosine receptors. To achieve this, we will add long timescale dynamics of adenosine receptor density to both of our models; up-regulation of A1 receptors has been proposed to underlie the observed sleep and performance responses to chronic sleep restriction. Model predictions will be compared to human data from a chronic sleep restriction protocol. (iv) Sleep/wake switch models predict that the stability of sleep and wake states should decrease as a sleep/wake transition approaches. Consequently, variability in firing rates and voltages of neurons in the sleep/wake switch should increase prior to a transition. We will test this prediction by comparing the predictions of both models to in vivo multi-unit recordings of the sleep/wake switch nuclei in freely behaving rats. Our work will: (i) Develop a standardized approach to modeling sleep physiology. (ii) Lead to the development of predictive models of sleep that are applicable to a wider range of domains, including sleep fragmentation and chronic sleep restriction. (iii) Provide the first direct quantitative test of the sleep/wake switch theory. These important goals are related but can also be achieved independently. Dr. Phillips' strong background in mathematical modeling of sleep and circadian rhythms provides him with the ideal expertise to tackle this project. He will also be greatly assisted by the experimental and mathematical expertise of his mentor, Dr. Klerman, who is head of the Analytic & Modeling Unit within the Division of Sleep Medicine (DSM) at Brigham & Women's Hospital, Harvard Medical School (HMS). The rich research environment at HMS provides extremely fertile ground for interdisciplinary and collaborative projects. In parallel with these research plans, we have prepared a detailed personal development plan to enable Dr. Phillips to build new skills and transition smoothly to independence. Dr. Phillips' immediate goals are to (i) expand his skills in computational neuroscience; (ii) receive focused training in biostatistics; (iii) build his experiece in teaching, mentorship, leadership, and organization; and (iv) produce high impact publications in the fields of sleep and circadian research. His plan to receive focused training in areas (i), (i), and (iii) is described in the proposal. The proposed research plan should also lead to high impact publications, due to its innovative approach, timeliness, and importance. This research and career development plan will build upon Dr. Phillips' existing research and expertise, and will open many new research directions for his career as an independent researcher. The proposed project will grant Dr. Phillips the necessary protected time to conduct research, achieve the necessary experience, and learn the requisite skills to achieve these long-term goals.

描述(申请人提供)：哺乳动物的睡眠在多个时间和空间尺度上受到调节。最近的实验发现揭示了脑干和下丘脑的神经元睡眠/唤醒控制系统在毫秒时间尺度上运行的重要性，这影响了生物体在小时时间尺度上的行为。这些系统包括相互抑制的促进睡眠的核团和促进觉醒的核团，它们共同构成了“睡眠/觉醒开关”。有人认为，这种开关的输入，包括位于哺乳动物下丘脑视交叉上核(SCN)的主昼夜节律起搏器的输出，以及睡眠平衡过程，产生了观察到的睡眠/觉醒周期。这一睡眠/觉醒转换理论已成为理解某些睡眠障碍(如发作性睡病)和衰老对睡眠的影响的基础。在过去的6年里，人们在不同的空间尺度上提出了该系统的几种数学模型，包括神经元质量(神经元种群水平)模型和神经网络(单个神经元水平)模型。这些模型被用来将行为表型与潜在的生理学联系起来，并测试关于我们睡眠理论模型的假设。然而，现有的模型在空间和时间尺度上受到限制，无法研究多尺度的相互作用，例如长期睡眠限制(长时间尺度)和睡眠碎片(短时间尺度)之间的相互作用。此外，关于潜在生理学的空间和时间属性的模型假设还没有得到测试。数学模型已被证明在定义正常和不正常的生理关系以及在许多与健康相关的领域测试潜在的治疗方法方面非常重要。因此，整合空间和时间尺度上的睡眠模型将提高对睡眠生理学和病理生理学的理解，并有助于设计干预措施。为了实现空间和时间尺度上睡眠模型的整合，我们将追求四个相互关联的目标。(I)确定睡眠/觉醒开关的神经质量模型和神经元网络模型在什么条件下预测相同的动力学。我们将开发现有神经质量模型的神经元网络版本，并测试参数异质性、网络规模和网络连通性的影响。(Ii)测试由于睡眠/唤醒开关的噪声输入，睡眠在短时间尺度上固有地碎片化的假设。为了实现这一点，我们将把噪声输入纳入神经质量和神经元网络模型，并将预测与住院患者协议中的人类数据进行比较。(Iii)测试慢性睡眠限制对睡眠和表现的影响是由于睡眠/觉醒开关和腺苷受体的长时间尺度动态之间的相互作用这一假设。为了实现这一点，我们将在我们的两个模型中添加腺苷受体密度的长时间标度动力学；A1受体的上调已被认为是观察到的睡眠和对慢性睡眠限制的表现反应的基础。模型预测将与慢性睡眠限制协议中的人类数据进行比较。(Iv)睡眠/唤醒切换模型预测，随着睡眠/唤醒转换的临近，睡眠和唤醒状态的稳定性应该会降低。因此，在转换之前，睡眠/觉醒开关中神经元的放电频率和电压的可变性应该增加。我们将通过将这两个模型的预测与自由行为大鼠的睡眠/觉醒开关核团的活体多单位记录进行比较来验证这一预测。我们的工作将：(I)开发一种标准化的睡眠生理学建模方法。(2)开发适用于更广泛领域的睡眠预测模型，包括睡眠碎片和长期睡眠限制。(3)首次对睡眠/觉醒转换理论进行直接量化检验。这些重要目标是相互关联的，但也可以独立实现。菲利普斯博士在睡眠和昼夜节律的数学建模方面的深厚背景为他提供了解决这一项目的理想专业知识。他还将得到他的导师Klerman博士的实验和数学专业知识的极大帮助，Klerman博士是哈佛医学院布里格姆妇女医院(HMS)睡眠医学部(DSM)分析和建模部门的负责人。HMS丰富的研究环境为跨学科和协作项目提供了极其肥沃的土壤。在这些研究计划的同时，我们还准备了一份详细的个人发展计划，使菲利普斯博士能够培养新的技能，并顺利过渡到独立。菲利普斯博士的近期目标是：(I)扩展他在计算神经科学方面的技能；(Ii)接受生物统计学方面的重点培训；(Iii)积累他在教学、指导、领导和组织方面的经验；(Iv)在睡眠和昼夜节律研究领域出版有影响力的出版物。他计划在(I)、(I)和(Iii)方面接受重点培训，这一计划在提案中作了说明。由于其创新的方法、及时性和重要性，拟议的研究计划还应导致出版影响较大的出版物。这项研究和职业发展计划将建立在菲利普斯博士现有研究和专业知识的基础上，并将为他作为一名独立研究员的职业生涯开辟许多新的研究方向。拟议的项目将给予菲利普斯博士必要的保护时间来进行研究，获得必要的经验，并学习实现这些长期目标所需的技能。