Audio-visual synchrony modulates the ventriloquist illusion and its neural/spatial representation in the auditory cortex
Audio-visual synchrony modulates the ventriloquist illusion and its neural/spatial representation in the auditory cortex
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DOI：
10.1016/j.neuroimage.2014.04.077
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发表时间：
2014-09-01
期刊：
影响因子：
5.7
通讯作者：
Hillyard, Steven A.
中科院分区：
文献类型：
--
作者：
Bonath, Bjoern;Noesselt, Toemme;Hillyard, Steven A.
我们感知系统的一项基本任务是将单个对象和事件的独特特征结合在一起形成统一的感知，即使这些特征以不同的感觉方式记录。在听觉和视觉输入在空间上不一致的情况下，它们仍然可能被感知为属于视觉刺激位置处的单个事件——这种现象被称为“口技幻觉”。本研究探讨了视听时间一致性如何影响口技幻觉，并通过功能磁共振成像（fMRI）表征其神经基础。根据之前的报告，在行为上，异步视听刺激与同步视听刺激相比，口技幻觉有所减少。在颞平面 (PT) 中一致观察到与口技效应相关的神经活动模式，外周感知的中枢声音的视觉刺激同侧的错觉相关 fMRI 信号减少，而中枢感知的外周声音的错觉相关 fMRI 信号对侧增加。此外，研究发现，同步和异步视听刺激产生的口技幻觉会优先激活 PT 内独立但相邻的区域。我们得出的结论是，PT 中神经活动的左右平衡代表了腹语幻觉背后的神经代码，在感知声音位置移动方向的对侧大脑半球有更大的活动。 (C) 2014 Elsevier Inc. 保留所有权利。
An essential task of our perceptual systems is to bind together the distinctive features of single objects and events into unitary percepts, even when those features are registered in different sensory modalities. In cases where auditory and visual inputs are spatially incongruent, they may still be perceived as belonging to a single event at the location of the visual stimulus - a phenomenon known as the 'ventriloquist illusion'. The present study examined how audio-visual temporal congruence influences the ventriloquist illusion and characterized its neural underpinnings with functional magnetic resonance imaging (fMRI). Behaviorally, the ventriloquist illusion was reduced for asynchronous versus synchronous audio-visual stimuli, in accordance with previous reports. Neural activity patterns associated with the ventriloquist effect were consistently observed in the planum temporale (PT), with a reduction in illusion-related fMRI-signals ipsilateral to visual stimulation for central sounds perceived peripherally and a contralateral increase in illusion-related fMRI-signals for peripheral sounds perceived centrally. Moreover, it was found that separate but adjacent regions within the PT were preferentially activated for ventriloquist illusions produced by synchronous and asynchronous audio-visual stimulation. We conclude that the left-right balance of neural activity in the PT represents the neural code that underlies the ventriloquist illusion, with greater activity in the cerebral hemisphere contralateral to the direction of the perceived shift of sound location. (C) 2014 Elsevier Inc. All rights reserved.