Multisensory perception: Audiovisual interactions under dynamic conditions

项目摘要 本研究探讨了听觉刺激对大脑皮层的影响的感觉间机制， 视觉感知单细胞神经生理学、事件相关脑电位和功能性 磁共振成像表明，大脑皮层中曾经被认为是单一感觉的神经元可以被刺激所驱动 从多种形式。此外，多传感器驱动的活动的时间是这样的，它不太可能是 这仅仅是因为来自解剖学上较晚的皮层区域的反馈。一组最近报道的行为效应 显示了从信息无关但伴随呈现的视觉感知的增强 听觉刺激似乎是这些多感觉机制的表现。然而，迄今为止，这些 还没有从任何共同的感觉间机制的角度来理解这些效应。 这项研究测试了视听时间封装假说，该假说认为， 瞬时听觉刺激定义了一个时间窗口，在该时间窗口内， 出现在该时间窗口中的视觉信息与时间上围绕的视觉信息的相互作用相隔离。这 该假设可以解释上述所有影响，并提出了超越这些影响的新预测， 这是本提案的重点。值得注意的是，已经报道的感觉间效应， 文献主要是伴随听觉刺激的视觉促进的例子。新的预测 我们从视听时间封装假说中得出的结论是视觉受损的例子， 感知伴随听觉刺激，这使得他们特别强大的检验假设。 总的想法是，如果视觉信息被伴随的听觉刺激所封装，那么它就跟随着 这些任务需要将封装的视觉信息与 不同的时间会受到影响。这一想法将在三个具体目标中得到检验。具体目标1测试的影响 视觉整合任务中的听觉刺激。具体目标2测试听觉刺激对过程的影响 通过该方法，运动刺激的可见余辉被有效地抑制，称为运动去模糊。具体 目的3测试听觉刺激对视觉信息被抑制的过程的影响， 眼球运动，称为扫视抑制。 如果得到证实，视听时间封装假说可以解释为什么人们容易受到影响， 当从事主要是视觉任务时听觉分心（例如，驾驶）。而且 封装过程可能是一种机制，在受损状态下，由于药物、酒精 或者疾病它也可能是一种随年龄增长而下降的机制。

PROJECT SUMMARY This research investigates intersensory mechanisms that underlie the influence of auditory stimuli on visual perception. Findings from single-cell neurophysiology, event-related brain potentials, and functional MRI indicate that neurons in cortical areas that were once thought to be unisensory can be driven by stimuli from multiple modalities. Moreover, the timing of multisensory-driven activity is such that it is unlikely to be due to just to feedback from anatomically later cortical areas. A set of recently reported behavioral effects showing the enhancement of visual perception from informationally unrelated but concomitantly presented auditory stimuli seem to be manifestations of these multisensory mechanisms. To date, however, these effects have not been understood in terms of any common intersensory mechanism. This research tests the audiovisual temporal-encapsulation hypothesis which states that an abrupt transient auditory stimulus defines a temporal window within which the representation of visual stimuli that appear in that time window are isolated from interaction with temporally surrounding visual information. This hypothesis can account for all of the effects reviewed above and it makes novel predictions beyond these, which are the focus of the present proposal. Significantly, the intersensory effects that have been reported in the literature are primarily examples of visual facilitation by concomitant auditory stimuli. The new predictions that we have derived from the audiovisual temporal encapsulation hypothesis are examples of impaired visual perception by concomitant auditory stimuli, which make them especially powerful for testing the hypothesis. The general idea is that if visual information is encapsulated by concomitant auditory stimuli, then it follows that tasks that require integration of that encapsulated visual information with information sampled at a different time will be impaired. This idea will be tested in three specific aims. Specific Aim 1 tests the effects of auditory stimuli in a visual integration task. Specific Aim 2 tests the effects of auditory stimuli on the processes by which visible persistence for moving stimuli is actively suppressed known, as motion deblurring. Specific Aim 3 tests the effects of auditory stimuli on the processes by which visual information is suppressed during eye movements, known as saccadic suppression. If confirmed, the audiovisual temporal-encapsulation hypothesis could explain why people are susceptible to auditory distraction when engaged in what are primarily visual tasks (e.g., driving). Moreover, the encapsulation process might be a mechanism that is subject to failure in impaired states due to drugs, alcohol or disease. It may also be a mechanism that is subject to decline with age.