Attention and Perceptual Learning

项目摘要 注意力和知觉学习(PL)是两种已知的提高视觉感知的机制，尽管如此， 在很大程度上，它们是分开研究的。我提议彻底调查 操纵对PL的隐蔽关注。PL涉及相对持久的(几周或几个月)对 有机体的知觉系统。这些变化提高了对环境中事件的响应能力，并 被认为是成年大脑神经可塑性的一种表现。PL已经被证明是 对各种感官形式中的许多刺激具有心理生理作用，并且通常高度特定于刺激和 任务。例如，如果观察员(在初始培训阶段)学习如何在特定地点执行任务 在视野中，他们后来(在测试阶段)在未经训练的地方没有显示出任何好处。注意力作用于 比PL短得多的时间刻度，是选择性和动态地 提高感知能力。隐蔽注意--在特定位置选择性地处理信息 没有眼球移动到该位置-提高对许多检测、辨别的感知性能 以及早期视觉中的本地化任务。我感兴趣的是外生性(非自愿)和内生性 (自愿)内隐注意影响PL的特征特异性，以及注意是否能与学习互动 为了克服这一限制，性能改进PL应运而生。我将使用视觉尺寸来 已经显示了PL的专一性和注意力的调节；例如，位置、方向和空间 频率研究与注意的影响相关的心理物理变化将导致 增加了对视觉系统可塑性的了解。是否以及如何以不同的形式 注意力增强成人大脑皮质的可塑性在理论上很重要，也有实际意义。普莱 可能是我们在职业和个人生活中视觉上做得最好的大部分基础，因此 巨大的基本利益和现实重要性。这个问题对于理解和 评估视觉系统受损后的康复潜力。我们自己对影响的研究 在目前的赠款期间对早期愿景的关注使我们处于独特的地位， 进行拟议的研究。初步研究表明，注意力在PL中扮演着一个关键且出人意料的角色。 我将描述每种类型的注意的影响，内源性的和外源性的，以实现以下目标： (1)跨视野视觉搜索的PL；(2)基本维度(例如，对比敏感度、方向)的PL 和空间分辨率)关于位置特异性，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) 学习和迁移的专一性；(4)意识缺失时的学习迁移。拟议的研究将利用 不同的心理物理程序有助于我们理解大脑可塑性如何改变视力 以及视觉处理如何与认知基础的其他大脑系统相互作用，在 特别的，注意。这些发现将具有理论上的相关性，并将有助于我们理解和 评估视觉系统受损后的康复潜力。

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.