Multisensory perception: Audiovisual interactions under dynamic conditions

描述(由申请人提供)：这项研究调查了听觉刺激对视觉知觉的影响所依据的感觉间机制。单细胞神经生理学、事件相关脑电位和功能磁共振的研究结果表明，曾经被认为是单一感觉的皮质区域的神经元可以受到来自多种形式的刺激的驱动。此外，多感官驱动活动的时机是这样的，它不太可能仅仅是由于来自解剖学上较晚的皮质区域的反馈。最近报道的一系列行为效应表明，与信息无关但伴随出现的听觉刺激可以增强视觉感知，这似乎是这些多感觉机制的表现。然而，到目前为止，这些影响还没有从任何常见的感觉间机制的角度被理解。这项研究测试了视听时间封装假说，该假说认为，突然的瞬时听觉刺激定义了一个时间窗口，在该时间窗口中出现的视觉刺激的表征与时间周围的视觉信息的相互作用是分开的。这一假设可以解释上述审查的所有影响，并做出了超出这些的新预测，这是本提案的重点。值得注意的是，文献中报道的感觉间效应主要是伴随听觉刺激促进视觉的例子。我们从视听时间封装假说中得到的新预测是伴随的听觉刺激导致的视觉知觉受损的例子，这使得它们对于检验该假说特别有效。一般的想法是，如果视觉信息被伴随的听觉刺激封装，那么需要将封装的视觉信息与在不同时间采样的信息进行整合的任务将受到损害。这一想法将在三个具体目标上得到检验。特定目标1测试视觉整合任务中听觉刺激的效果。《特定目标2》测试了听觉刺激的效果，通过这一过程，运动刺激的视觉持续性被主动抑制，称为运动去模糊。《特定目标3》测试了听觉刺激对视觉信息在眼动过程中被抑制的影响，这种过程被称为扫视抑制。如果得到证实，视听时间封装假说可以解释为什么人们在从事主要是视觉任务(如驾驶)时容易受到听觉干扰的影响。此外，包裹过程可能是一种机制，在受损状态下容易因药物、酒精或疾病而失败。这也可能是一种随年龄增长而衰退的机制。

DESCRIPTION (provided by applicant): 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 o 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 stimulion 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.