Neural time-integration underlying higher cognitive function

高级认知功能背后的神经时间整合

• 批准号: 8247075
• 负责人: Alexander C Huk
• 金额: $ 35.24万
• 依托单位: UNIVERSITY OF TEXAS AT AUSTIN
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8247075
• 关键词: Address; Area; Attention; Behavior; Behavioral; Brain; Brain region; Cells; Characteristics; Cognitive; Complex; Decision Making; Delayed Memory; Discrimination; Eye Movements; Goals; Health; Human; Intention; Level of Evidence; Link; Location; Maintenance; Measurement; Memory; Monkeys; Motion; Motor; Neurologic; Neurons; Performance; Photic Stimulation; Physiological; Primates; Process; Property; Prosthesis; Ramp; Reporting; Research; Rewards; Robotics; Role; Saccades; Sampling; Sensorimotor functions; Sensory; Short-Term Memory; Signal Transduction; Stimulus; Testing; Time; Visual; Work; cognitive function; computer framework; design; expectation; flexibility; lateral intraparietal area; nonhuman primate; oculomotor; oculomotor behavior; relating to nervous system; research study; response; stimulus interval; visual memory; visual stimulus

DESCRIPTION (provided by applicant): The long-term goal of this research is to understand the basic neural computations that transform sensory signals into representations that support cognitive processes and guide subsequent actions. The research proposed here tests how signals flowing through the lateral intraparietal area (LIP) underlie processes of accumulating and remembering sensory evidence for the purposes of guiding eye-movements. We approach this topic by adapting a computational framework derived from previous work using a direction-discrimination paradigm, and extending it to a wider range of behavioral tasks, experimental phenomena, and theoretical approaches. Our primary goal is to test the degree to which the persistent and ramping activity in LIP reflects neural time-integration, and how this computation relates to sensory stimulation, working memory, and oculomotor planning. Our secondary goal is to better integrate the quantitative inferences available from the direction-discrimination paradigm and time-integration hypothesis to other work on oculomotor computations. We have previously demonstrated that neural activity in area LIP reflects the temporal accumulation of noisy sensory evidence during the performance of a motion direction decision- making task. Because LIP activity is driven strongly by the onset of such a visual target, it is necessary to test whether temporal integration in LIP depends on the presence of a visual stimulus within the response field. We will also assess the cognitive role of persistent activity in LIP. If the persistent activity in LIP supports the combination of multiple pieces of evidence acquired at different times, LIP activity during interleaved periods of stimulus viewing and working memory should reflect the time integral of the sensory evidence. We will test this hypothesis by incorporating a blank memory delay period between successive periods of sensory evidence, and evaluating whether activity during the delay period reflects the accumulated and maintained level of evidence. We will further investigate the relationship between LIP activity and cognitive function by performing a similar task in which two stimuli must be compared, instead of combined. In short, we will manipulate sensory, cognitive, and motor variables to assess the degree to which LIP activity appears to support time integration when: (1) visual stimulation of the response field is manipulated; (2) successive periods of accumulation and maintenance of sensory evidence occur; and (3) the specific eye-movement is not known during the formation of a decision. These measurements will also provide several opportunities to appreciate cell-by- cell diversity in sensory, memory, decision, and motor responses. PUBLIC HEALTH RELEVANCE Primate behavior is intelligent, flexible, and complex. These behavioral strengths often derive from the ability of human and nonhuman primates to combine multiple pieces of evidence acquired at different times. A thorough understanding of how the brain performs this "temporal integration" will benefit neurological treatments, as well as inform technical applications involved in the control and design of intelligent prosthetics and robotics.

描述（由申请人提供）：这项研究的长期目标是了解将感觉信号转化为支持认知过程并指导后续行动的表示的基本神经计算。这里提出的研究测试了流经外侧顶叶区（LIP）的信号如何成为积累和记忆感官证据以引导眼球运动的过程的基础。我们通过采用方向辨别范式改编从以前的工作中得出的计算框架来解决这个主题，并将其扩展到更广泛的行为任务、实验现象和理论方法。我们的主要目标是测试 LIP 中持续和斜坡活动反映神经时间整合的程度，以及该计算与感觉刺激、工作记忆和动眼神经规划的关系。我们的第二个目标是更好地将方向辨别范式和时间积分假设中可用的定量推论整合到动眼神经计算的其他工作中。我们之前已经证明，LIP 区域的神经活动反映了在执行运动方向决策任务期间噪声感官证据的时间积累。由于 LIP 活动是由此类视觉目标的出现强烈驱动的，因此有必要测试 LIP 中的时间整合是否取决于响应场内视觉刺激的存在。我们还将评估持续活动在 LIP 中的认知作用。如果 LIP 中的持续活动支持在不同时间获取的多个证据的组合，则刺激观看和工作记忆的交错期间的 LIP 活动应该反映感觉证据的时间积分。我们将通过在连续的感官证据周期之间加入空白记忆延迟期来检验这一假设，并评估延迟期内的活动是否反映了证据的积累和维持水平。我们将通过执行类似的任务来进一步研究 LIP 活动和认知功能之间的关系，其中必须比较而不是组合两个刺激。简而言之，我们将操纵感觉、认知和运动变量来评估 LIP 活动在何种程度上支持时间整合：(1) 操纵反应场的视觉刺激； (2) 感官证据的连续积累和维持发生； (3)在做出决定的过程中具体的眼球运动是未知的。这些测量还将提供一些机会来欣赏感觉、记忆、决策和运动反应中各个细胞的多样性。公共卫生相关性 灵长类动物的行为聪明、灵活且复杂。这些行为优势通常源自人类和非人类灵长类动物将不同时间获得的多个证据结合起来的能力。彻底了解大脑如何执行这种“时间整合”将有利于神经治疗，并为智能假肢和机器人的控制和设计所涉及的技术应用提供信息。