Neurophysiological Correlates of Information Processing

本研究的主要目的是对听觉感知的刺激驱动过程提供更详细的了解。我们将使用事件相关电位（ERPs）的高时间分辨率，结合行为方法，在不同的实验条件下，比较刺激驱动的听觉过程的结果与注意处理相同声音所产生的感知。这将使我们能够评估感觉输入和行为反应之间的处理阶段。这项提议有三个主要目的。一是确定无人值守声学信息的处理程度。四个实验解决了这个问题。其中一个测试的是对无人看管声音的处理能力。另一个决定了听觉特征整合的过程是否需要注意。第三个测试的假设是，当注意力集中在一个单一的声源上时，听觉系统会组织来自多个无人看管的声源的信息。第四部分研究刺激情境对听觉事件形成的影响。第二个目标是了解注意力和刺激驱动的过程是如何相互作用的。两个实验解决了这个问题。一项研究知觉与刺激驱动的听觉事件形成的关系，另一项研究注意在听觉流形成中的作用。第三个目的是研究注意力对早期感觉分组过程的影响。一个实验将检验自上而下的加工可以改变刺激驱动的声音组织的假设。中央听觉处理缺陷被认为在许多认知障碍（如自闭症或阅读障碍）中起着关键作用。使用电生理测量，结合行为方法，来描述刺激驱动的过程，有助于听觉感知，这有助于提高我们对受损加工的理解，这对发展康复治疗至关重要。此外，由于受试者的反应不需要获得ERP成分（如N1和MMN），因此该方法有可能成为诊断导致认知受损的中枢性听觉加工缺陷的重要非侵入性工具。

The broad objective of the proposed research is to provide a more detailed understanding of the stimulus-driven processes that contribute to auditory perception. We will use the high temporal resolution of event-related potentials (ERPs) in conjunction with behavioral methods to compare the outcome of stimulus-driven auditory processes with the perception resulting from attentive processing of the same sounds, across various experimental conditions. This will allow us to evaluate the processing stages between sensory input and behavioral response. There are three main aims of the proposal. One is to determine the extent of processing of unattended acoustic information. Four experiments address this aim. One tests the processing capacity for unattended sounds. Another determines whether the process of auditory feature integration requires attention. A third tests the hypothesis that the auditory system organizes information from multiple unattended sources when attention is directed to a single acoustic source. The fourth investigates stimulus context effects on auditory event formation. A second aim is to understand how attention and stimulus-driven processes interact. Two experiments address this aim. One investigates how perception relates to stimulus-driven auditory event formation and another, the role of attention in auditory stream formation. The third aim is to investigate effects of attention on early sensory grouping processes. One experiment will test the hypothesis that top-down processing can modify the stimulus- driven sound organization. Deficits in central auditory processing are thought to play a key role in many cognitive disorders (e.g., autism or dyslexia). Using electrophysiological measures, in conjunction with behavioral methods, to delineate the stimulus-driven processes that contribute to auditory perception can help advance our understanding of impaired processing, which is essential for developing rehabilitative treatments. Furthermore, because subject response is not needed for obtaining the ERP components (such as N1 and MMN), this methodology has the potential to be an important non-invasive tool for diagnosis of central auditory processing deficits that contribute to impaired cognition.