A1 neural basis of frequency discrimination learning

A1 鉴频学习的神经基础

• 批准号: 6883940
• 负责人: David T Blake
• 金额: $ 5.42万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2005-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6883940
• 关键词: Aotus; auditory cortex; auditory discrimination; auditory feedback; auditory stimulus; behavior test; conditioning; discrimination learning; implant; microelectrodes; neural plasticity; operant conditionings; sound perception; stimulus /response

DESCRIPTION (provided by applicant): This application outlines a direct study of the mechanisms of auditory learning. Animals are capable of making new associations between positive reinforcers, the sensory context that preceded them, and the motor acts that cause them. The proposed studies will use multiple microelectrode implant technology to record simultaneously from a large number of neurons in auditory cortex throughout a period in which an animal acquires a new association. The specific intent will be to observe how the auditory cortex representation of the sensory context is altered by the learning. The monkeys will be trained to discriminate short sound tones. As they begin to perform the task to receive rewards, their brain learning machinery is engaged and causes unavoidable changes in how sounds are represented. Data will be collected in parallel, in terms of the animal's perceptual capabilities and the response properties of neurons in auditory fields within and outside the behavioral tasks. The use of implants in neural systems has advanced much in the last decade; this study will apply that technology to study learning. In the first phase of training, animals will respond to short tones that are just higher in frequency than fixed comparison tones. Preliminary studies have shown that if the target stimulus comes from a fixed range, the representation of that frequency range grows and intensifies. After this initial phase, the animals will perform the same frequency discrimination task using randomized frequencies for comparison and target tone pips. A control experiment will replicate the trials of the first phase of training in naive animals that are only passive listeners. These studies should contribute to defining the plastic properties of cortical fields as dynamic learning neural networks. Such networks are most easily understood in terms of their initial sets of connections and their learning rules. This study will isolate and test different hypotheses for learning rules, and will lead to a greater understanding of the adaptive role of the cerebral cortex in general, both in instrumental learning and in classical conditioning.

描述（由申请人提供）：本申请概述了对听觉学习机制的直接研究。动物能够在积极的增强剂，它们之前的感觉环境以及导致它们的运动作用之间建立新的关联。拟议的研究将使用多个微电极植入物技术在整个动物获得新关联的时期中同时从听觉皮层中的大量神经元记录。具体意图是观察如何通过学习来改变感觉上下文的听觉皮层表示。猴子将接受训练以区分短音调。当他们开始执行获得奖励的任务时，他们的大脑学习机制会参与其中，并在声音的表示方式中引起不可避免的变化。数据将根据动物的感知能力以及行为任务内外的听觉领域中神经元的响应特性并行收集数据。在过去的十年中，在神经系统中使用植入物已经进步了很多。这项研究将应用该技术来学习学习。在训练的第一阶段，动物会响应频率刚好高于固定比较音调的短音调。初步研究表明，如果目标刺激来自固定范围，则该频率范围的表示会增强并加剧。在此初始阶段之后，动物将使用随机频率进行相同的频率歧视任务，以进行比较和目标音调。控制实验将复制仅被动听众的幼稚动物训练的第一阶段试验。这些研究应有助于将皮质场的塑性特性定义为动态学习神经网络。从初始连接及其学习规则方面，最容易理解此类网络。这项研究将隔离和检验学习规则的不同假设，并在一般来说，在工具学习和经典条件中，对大脑皮层的适应性作用有了更大的了解。