Neural mechanisms of color

颜色的神经机制

• 批准号: 8595559
• 负责人: Bevil R Conway
• 金额: $ 36.85万
• 依托单位: WELLESLEY COLLEGE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8595559
• 关键词: Accounting; Afterimage; Animals; Anterior; Appearance; Area; Automobile Driving; Biological; Biological Models; Blindness; Brain; Brain region; Bypass; Cells; Cerebral cortex; Code; Cognition; Color; Color blindness; Complement; Complex; Coupled; Data; Diagnosis; Discrimination; Disease; Etiology; Eye; Face; Frequencies; Functional Magnetic Resonance Imaging; Hospitals; Human; Hybrids; Impaired cognition; Inferior; Knowledge; Lesion; Link; Location; Macaca mulatta; Measures; Mediating; Memory; Mental disorders; Microelectrodes; Modeling; Monkeys; Nature; Neurons; Pattern; Perception; Population; Probability; Process; Property; Psychometrics; Psychophysics; Relative (related person); Research; Retinal Cone; Role; Sampling; Scheme; Series; Shapes; Signal Transduction; Staging; Stereotyping; Stimulus; Stroke; Temporal Lobe; Testing; Texture; Time; Tissues; Vision; Visual; Visual Perception; Visual impairment; Weight; Work; achromatopsia; base; color category; color processing; experience; interstitial; microstimulation; nervous system disorder; neural circuit; neuromechanism; novel; public health relevance; receptive field; relating to nervous system; research study; response; treatment strategy

The links between neural activity, perception and cognition are poorly understood. This proposal advances color as a model system to fill these gaps in knowledge. Color is an essential feature of visual experience, and much is known about how cone signals from the eye are encoded and transmitted to the cortex. But surprisingly little is known about the mechanisms that decode these signals to bring about perceived colors and guide perceptual decisions. Two competing decoding schemes have been proposed: an interval code, which requires a population of cells with sharp chromatic tuning that together encompass all color space, coupled with a winner- take-all rule; and a population code, which needs at minimum two groups of color-tuned neurons, coupled with a weighted-average rule. It is unclear which groups of neurons within the cerebral cortex are involved. One hint comes from lesions of inferior temporal cortex (IT) in rhesus monkeys, which cause profound color blindness similar to the achromatopsia that accompanies certain cerebral strokes in humans. IT is an expansive region of tissue implicated in many aspects of object coding, and the functional organization of IT is poorly understood. Without this information, it is almost impossible to know which neurons are the most likely to be contributing to color processing. Possible organizational schemes include a modular model comprising uniquely specialized areas; a distributed-processing model; or a hybrid model, consisting of a series of hierarchical stages, each comprising a full complement of functional subregions. Aim 1 calls for a battery of functional magnetic resonance imaging (fMRI) experiments in alert monkey that will determine the distribution of color-coding regions in IT, their functional connectivity and relationship to other functionally defined regions to test which model accounts for the organization of IT. Aim 2 outlines fMRI-guided microelectrode recordings of IT color regions paired with microstimulation while monkeys perform color tasks, to test the causal link between neural activity and perceived color, and to determine which of the two decoding schemes, interval or population, is implemented in IT. The research will uncover principles by which perception and cognition emerge from the activity of neural circuits. This information is required to understand the etiology, diagnosis, and treatment of mental illnesses and strokes that impair cognition and perception. Moreover, the work will establish the relationship of higher-order areas between humans and monkeys, which is necessary in order to use monkeys as models of human vision and disease.

人们对神经活动、感知和认知之间的联系知之甚少。这个提议 将颜色作为模型系统来填补这些知识空白。颜色是一个重要特征 视觉体验的影响，并且人们对来自眼睛的视锥细胞信号如何编码和 传送到皮质。但令人惊讶的是，人们对解码的机制知之甚少。 这些信号带来感知颜色并指导感知决策。两人竞争 已提出解码方案：间隔码，需要一群细胞 具有锐利的色彩调整，共同涵盖所有色彩空间，再加上获胜者 - 通吃规则；和人口代码，至少需要两组经过颜色调整的 神经元，加上加权平均规则。目前尚不清楚神经元内有哪些神经元组 大脑皮层都参与其中。一个线索来自于下颞叶皮层（IT）的损伤 恒河猴，会导致严重的色盲，类似于色盲症 伴随人类的某些脑中风。 IT 是涉及的广泛组织区域 在对象编码的许多方面，人们对 IT 的功能组织知之甚少。 如果没有这些信息，几乎不可能知道哪些神经元最有可能是 有助于色彩处理。可能的组织方案包括模块化模型 包括独特的专业领域；分布式处理模型；或混合模型， 由一系列分层阶段组成，每个阶段都包含完整的功能补充 次区域。目标 1 需要一系列功能性磁共振成像 (fMRI) 在警觉猴子身上进行的实验将确定 IT 中颜色编码区域的分布， 它们的功能连接性以及与其他功能定义区域的关系，以测试哪些 IT 组织的模型。目标 2 概述了功能磁共振成像引导的微电极记录 当猴子执行颜色任务时，IT颜色区域与微刺激配对，以测试 神经活动和感知颜色之间的因果关系，并确定两者中的哪一个 解码方案（间隔或总体）在 IT 中实施。研究将揭示 感知和认知从神经回路活动中产生的原理。这 了解精神疾病的病因、诊断和治疗需要信息 以及损害认知和知觉的中风。此外，这项工作将建立 人类和猴子之间的高阶区域的关系，这是为了 使用猴子作为人类视觉和疾病的模型。