Attention and Perceptual Learning

项目摘要 注意力和知觉学习（PL）是两种已知的改善视觉感知的机制， 大多数情况下，它们是分开研究的。我建议彻底调查 操纵PL上的内隐注意。PL涉及相对持久（数周或数月）的变化， 有机体的感知系统。这种变化提高了对环境中事件的反应能力， 被认为是成人大脑神经可塑性的表现。PL已被证明 在各种感觉方式中的许多刺激都是精神病性的，并且通常对刺激和 任务例如，如果观察者（在初始训练阶段）学习如何在特定位置执行任务， 在视野中，他们后来（在测试阶段）在未经训练的位置没有显示出任何好处。注意操作 一个比PL更短的时间尺度，是选择性和动态地 提高感知性能。内隐注意-在给定位置对信息的选择性处理 没有眼睛移动到该位置-提高了许多检测、辨别 和定位任务。我感兴趣的是外源性（非自愿）和内源性 （自愿）内隐注意影响PL的特征特异性，以及注意与学习是否相互作用 为了克服PL产生的性能改进的这种限制。我将使用视觉尺寸 已经显示了PL特异性和注意力调节;例如，位置、方向和空间 频率.研究与注意力对PL的影响相关的心理物理变化将导致 增加对视觉系统可塑性的理解。关于不同形式的 注意力增强成人大脑皮层的可塑性在理论上是重要的，并具有实际的后果。PL 可能是我们在职业和个人生活中在视觉上做得很好的大部分事情的基础，因此也是 巨大的基础利益和现实意义。这个问题对于理解和 评估视觉系统受损后的康复潜力。我们自己的研究表明 在当前赠款期间对早期视力的关注使我们处于一个独特的位置， 开展拟议的研究。初步研究表明，注意在PL中起着关键的和意想不到的作用。 我将描述每种类型的注意力的影响，内源性和外源性，以实现以下目标： (1)在整个视野中视觉搜索的PL;（2）基本尺寸的PL（例如，对比敏感度、方向 和空间分辨率），考虑到视网膜距离、皮质距离 和注意窗口的大小;（3）关于特征的PL（例如，对比敏感度，方向） 学习和迁移的特异性;（4）在没有意识的情况下的PL。该研究将利用 不同的心理物理过程，有助于我们理解大脑可塑性如何改变视觉， 以及视觉处理如何与其他认知基础的大脑系统相互作用， 特别注意这些发现将具有理论相关性，并将有助于我们理解和 评估视觉系统损伤后的康复潜力。

Project Summary Attention and perceptual learning (PL) are two mechanisms known to improve visual perception, though, for the most part, they have been studied separately. I propose to thoroughly investigate the effects of manipulating covert attention on PL. PL involves relatively long-lasting (weeks or months) changes to an organism's perceptual system. Such changes improve the ability to respond to events in the environment and are considered a manifestation of neural plasticity in the adult brain. PL has been demonstrated psychophysically for many stimuli in various sensory modalities, and is often highly specific to stimulus and task. For instance, if observers learn (in the initial training phase) how to perform a task at a particular location in the visual field, they later (in the testing phase) show no benefit at untrained locations. Attention operates on a much shorter timescale than PL and is the most important mechanism that selectively and dynamically improves perceptual performance. Covert attention - the selective processing of information at a given location without eye movements to that location - improves perceptual performance on many detection, discrimination and localization tasks in early vision. I am interested in how exogenous (involuntary) and endogenous (voluntary) covert attention affect the hallmark specificity of PL, and whether attention can interact with learning to overcome this limitation to the improvement in performance PL engenders. I will use visual dimensions for which both PL specificity and modulation by attention have been shown; e.g., location, orientation and spatial frequency. Investigating the psychophysical changes associated with the effects of attention on PL will lead to increased understanding of plasticity in the visual system. The question of whether and how different forms of attention enhance plasticity in the adult cortex is important theoretically and has practical consequences. PL probably underlies most of what we do well visually in our professional and personal lives and is thus of enormous basic interest and practical importance. This question is also crucial for understanding and evaluating the potential of rehabilitation following damage to the visual system. Our own studies on the effects of attention on early vision conducted during the period of the current grant place us in a unique position to conduct the proposed research. Pilot studies indicate that attention plays a pivotal and unanticipated role in PL. I will characterize the effects of each type of attention, endogenous and exogenous, for the following aims: (1) PL in visual search across the visual field; (2) PL of basic dimensions (e.g., contrast sensitivity, orientation and spatial resolution) with regard to location specificity, taking into account retinal distance, cortical distance and the size of the attentional window; (3) PL with regard to feature (e.g., contrast sensitivity, orientation) learning and transfer specificity; (4) PL in the absence of awareness. The proposed research will utilize different psychophysical procedures to contribute to our understanding of how brain plasticity alters vision as indicated by PL, and how visual processing interacts with other brain systems underlying cognition, in particular, attention. The findings will have theoretical relevance and will contribute to our understanding and evaluation of potential of rehabilitation following damage to the visual system.