The Mechanisms of Perceptual Learning

描述(由申请人提供)：大脑如何适应新的环境，同时保护其结构免受不必要信息的持续轰炸的修改？本提案的目的是阐明低水平感觉系统如何解决这种稳定性-可塑性难题。直到最近，人们还认为低水平的感觉系统是僵硬的，因此对环境变化具有抵抗力，只有持续并专注于原始特征，这些系统才能被修改。然而，最近的一系列研究表明，低水平的视觉系统比之前认为的更具可塑性。低于阈值的、与任务无关的特征的性能改进没有注意到该特征(Watanabe等人，2001、2002；Seitz&Watanabe，2003)。如果注意力不能打开学习的大门，那么是什么保护感觉系统免受不必要的修改呢？为了解决这个问题，我们提出了一系列心理物理实验来研究低水平感觉系统中的可塑性是如何被控制的。这些实验将探索早期感觉系统中学习和可塑性的不同方面；学习的关联性、学习所需的加工深度、学习的动力学、学习的干扰以及相同或不同的路径或感觉模式的学习。成功地阐明这些学习门控机制将极大地有助于我们理解在低水平视觉阶段稳定性-可塑性困境是如何解决的。

DESCRIPTION (provided by applicant): How can the brain adapt to new environments while protecting its architecture from modification from the continual bombardment of undesirable information? The goal of the present proposal is to clarify how low-level sensory systems solve this stability-plasticity dilemma. Until recently, it was thought that low-level sensory systems were rigid and, therefore, resistant to environmental changes, and that only with persistent and focused attention on primitive features can these systems be modified. However, recently a series of studies have indicated that the low-level visual system is significantly more plastic than previously thought. Performance improvement on a sub-threshold, task-irrelevant feature occurred without attention to that feature (Watanabe et al, 2001,2002; Seitz & Watanabe, 2003). If attention does not gate learning, then what protects the sensory systems from undesirable modification? To address this question, we propose a series of psychophysical experiments to investigate how plasticity is gated in low-level sensory systems. These experiments will explore different aspects of learning and plasticity in the early sensory systems; the associability of learning, depth of processing required for learning, dynamics of learning, interference of learning, and learning across the same or different pathways or sensory modalities. Successful clarification of these gating mechanisms for learning will greatly contribute to our understanding of how the stability-plasticity dilemma is solved in low-level visual stages.