Temporal Strategies in Visual Cortex

描述（由申请人提供）：行为依赖于对感官信息的可靠解释以及该信息与动作的灵活关联。因此，它取决于感觉神经元对信息的准确编码和根据任务约束对这些感觉信号的适当解码。在感官环境快速变化的情况下，这些过程的速度可能至关重要：无法快速应对迫在眉睫的威胁可能是致命的。在之前的资助申请中获得的证据表明，单个神经元在数十毫秒内的活动可以准确地编码运动信息。同样短暂的活动时间也强烈预测了动物在自然注视任务中的行为选择，因此可能在快速决策中发挥关键作用。拟议的实验将探索这种精度如何在神经群体中分布，以及如何通过训练或任务需求来改变。动物将接受需要快速分析运动信息的任务训练。同时记录的神经元活动和行为将被分析，以推断的精确性和可靠性的感觉信号和它们对行为选择的影响。在第一个具体的目标，可靠的感觉信息的分布在皮层人口将进行调查。在第一个实验中，附近的神经元将同时被运动刺激激活，以研究活动相关性如何改善或降低感觉信息及其与行为结果的关联。在第二个实验中，精确性和可靠性的刺激依赖性将被用来推断这些因素如何在广泛的激活神经元群体中变化。在第二个具体目标中，将在获得快速运动检测能力的过程中记录单个神经元，以研究这种精确度的学习程度。在第三个具体的目标，刺激和概率操纵将被用来揭示负责这种精确的神经元活动的具体任务参数。由于所有这些任务都极具挑战性，它们将有助于揭示决策准确性和速度的潜在限制。通过同时解决大脑内感觉编码和解码的可靠性和精确性，这些研究还可以为开发有效的假肢神经接口提供有价值的信息。 公共卫生相关性：基于感知信息的小时期的决策通常具有生死攸关的重要性，不仅在自然界如此，每次我们穿过忙碌的十字路口或在忙碌的高速公路上导航时也是如此。然而，没有现有的模型能够解释我们的大脑如何能够快速可靠地处理简短的信息，并随后根据这些信息计划和执行适当的行动。该提案的目标是通过研究特定大脑区域的神经活动如何能够精确地表示视觉信息并影响快速决策过程中的行为来揭示这种能力的生理基础。

DESCRIPTION (provided by applicant): Behavior relies on the reliable interpretation of sensory information and the flexible association of that information with actions. It therefore depends on the both the accurate encoding of information by sensory neurons and the appropriate decoding of these sensory signals according to task constraints. In circumstances involving rapid changes in the sensory environment, the speed of these processes can be of paramount importance: an inability to quickly respond to a looming threat can be fatal. Evidence acquired in the previous grant submission demonstrates that the activity of single neurons over tens of milliseconds can accurately and precisely encode motion information. The same brief periods of activity were also strongly predictive of behavioral choice when animals were engaged in a natural foveation task, and therefore potentially play a pivotal role in rapid decision making. The proposed experiments will explore how such precision is distributed among neural populations and how it is altered by training or task demands. Animals will be trained in tasks requiring the rapid analysis of motion information. Simultaneous recording of neuronal activity and behavior will be analyzed to infer the precision and reliability of sensory signals and their influence on behavioral choice. In the first specific aim, the distribution of reliable sensory information over a cortical population will be investigated. In the first experiment, nearby neurons will be simultaneously activated by a motion stimulus in order to examine how activity correlations might improve or degrade sensory information and its association with behavioral outcome. In the second experiment, the stimulus dependence of precision and reliability will be used to infer how these factors vary across a broad population of activated neurons. In the second specific aim, recordings of individual neurons will be made during the acquisition of proficiency in rapid motion detection to study the extent to which this precision is learned. In the third specific aim, stimulus and probability manipulations will be used to reveal the specific task parameters responsible for such precise neuronal activity. Because all of these tasks are highly challenging, they will help reveal the underlying constraints on the accuracy and speed of decision making. By simultaneously addressing the reliability and precision of sensory encoding and decoding within the brain, these studies could also provide valuable information for the development of effective neural interfaces for prosthetics. PUBLIC HEALTH RELEVANCE: Decisions based on small epochs of perceptual information are often of life-or-death importance not only in nature but every time we cross a busy intersection or navigate a busy highway. However, no existing model is able to explain how our brains are able to rapidly and reliably process brief amounts of information and subsequently plan and execute appropriate actions on the basis on that information. This goal of this proposal is to reveal the physiological basis of such capabilities by investigating how neural activity in a specific brain area is able to precisely represent visual information and influence behaviors during the course of rapid decision making.