Psychophysics & Neuroimaging Studies of the Multisensory Temporal Binding Window

描述（由申请人提供）：大脑结合传入的听觉和视觉刺激的能力主要取决于这种多感官信息的时间结构。具体地说，存在视听整合的时间窗口，在该时间窗口内刺激被绑定并因此被处理为单一的感知事件。虽然以前的工作已经表明，这种多感官的时间窗口是有点任务和上下文相关的，有普遍的协议，窗口的大小是几百毫秒的顺序。此外，最近的工作已经证明了这个时间窗口的延展性，表明重复呈现的异步视觉配对可以改变其边界。虽然这项工作强调了窗口可以及时移动以反映最近的感官体验，但没有研究检查窗口的大小是否可以改变。在目前的建议中，我们试图研究这个问题，它围绕着两个具体目标。首先，使用知觉训练范例，我们将寻求缩短多感觉时间窗的大小。其次，使用功能磁共振成像，我们将检查这个时间绑定过程的神经基础，以及如何识别的网络随着窗口大小的变化而变化。为了实现这些目标，我们将使用视听一致性任务来描绘时间窗口的大小。接下来，我们将开发一个一致性判断训练范例，其中每个判断都与其正确性的反馈配对。我们期望这种训练范式将导致时间绑定窗口的显着缩小，并且，也许更重要的是，这些效果将扩展到多感觉时间功能的其他测量（即，他们会概括的）。我们已经收集到了令人兴奋的初步数据，支持多感觉时间绑定窗口的显着缩小，以进行一致性判断。此外，这些影响似乎普遍适用于其他任务，并且是持久的。更重要的是，在一个初步的数据集中，我们已经突出显示了在多感官知觉训练后似乎发生改变的大脑区域。这些研究将有助于更好地定义成人多感觉时间过程的可塑性及其神经基础，我们希望这项工作将为未来针对神经生物学疾病的补救计划奠定基础（例如，阅读障碍，自闭症），其中有越来越多的证据表明，在多感官的时间功能中断。

DESCRIPTION (provided by applicant): The brain's ability to bind incoming auditory and visual stimuli depends critically on the temporal structure of this multisensory information. Specifically, there exists a temporal window of audiovisual integration within which stimuli are bound and consequently processed as a unitary perceptual event. Although previous work has shown that this multisensory temporal window is somewhat task-and context-dependent, there is general agreement that the size of the window is on the order of several hundred milliseconds. Furthermore, more recent work has demonstrated a malleability of this temporal window by showing that repeated presentations of asynchronous auditory-visual pairings can shift its boundaries. Although this work highlights that the window can be shifted in time to reflect recent sensory experience, no studies have examined whether the size of the window can be altered. In the current proposal, we seek to examine this issue, which is framed around two specific aims. First, using a perceptual training paradigm, we will seek to shorten the size of the multisensory temporal window. Second, using fMRI, we will examine the neural basis of this temporal binding process and how the identified networks change with changing window size. To accomplish these aims, we will use an audiovisual simultaneity task to delineate the size of the temporal window. Next, we will develop a simultaneity judgment training paradigm wherein each judgment is paired with feedback as to its correctness. It is our expectation that this training paradigm will result in a significant narrowing of the temporal binding window, and, perhaps more importantly, that these effects will extend to other measures of multisensory temporal function (i.e., they will generalize). We have already gathered exciting preliminary data in support of a significant narrowing of the multisensory temporal binding window for simultaneity judgments. In addition, these effects appear to generalize to other tasks and to be long-lasting. What's more, in a preliminary data set, we have highlighted brain areas that appear to be altered after multisensory perceptual training. These studies will help to better define the plastic capacity of multisensory temporal processes in adults and their neural underpinnings, work that we hope will form a foundation for future remediation programs targeted toward neurobiological disorders (e.g., dyslexia, autism) in which there is growing evidence of disruptions in multisensory temporal function.