Disentangling unisensory and multisensory components in audiovisual integration using a novel multifrequency fMRI spectral analysis
Disentangling unisensory and multisensory components in audiovisual integration using a novel multifrequency fMRI spectral analysis
复制标题
DOI：
10.1016/j.neuroimage.2010.04.186
复制
发表时间：
2010-08-15
期刊：
影响因子：
5.7
通讯作者：
Amedi, Amir
中科院分区：
文献类型：
--
作者：
Hertz, Uri;Amedi, Amir
世界上的事件是通过多个感觉输入来调节的，这些输入根据分工原则在特定的单一感觉区域分别进行处理，然后需要整合以产生统一的感知。如何做到这一点仍不清楚。例如，最近的证据表明，主要区域存在跨模式激活。我们开发了一种新的方法来研究多感觉整合，使用多频谱分析来研究多感觉背景下的音频和视频流的处理。在相同的实验条件下，听觉和视觉刺激分别以不同的呈现频率传递，因此可以通过在不同呈现频率下应用傅立叶谱分析来检测。研究发现，尽管存在多感官环境，初级听觉和视觉区域的耳蜗区和视网膜区的组织结构仍然完好无损。在楔前脑区也发现了听觉反应，提示它可能是一个对纯音刺激作出反应的新的听觉区域，并作为一种新的感觉偏好梯度的一端，该梯度从POG延伸到距骨沟。在感觉偏好梯度的中间区域和初级听觉区域都检测到了额外的视听区域会聚。有趣的是，听觉和视频流的输入/输出同步率产生了第三个交互频率，该频率可以独立分析以揭示更高阶的视听交互反应。这些结果是在一个紧凑和自然的多感官实验条件下检测的，与以前的方法相比有几个优点。该方法可以进一步被实现来研究任何类型的相互作用，在感觉模式内和跨感觉模式。(C)2010 Elsevier Inc.保留所有权利。
Events in the world are mediated through multiple sensory inputs which are processed separately in specific unisensory areas according to the division-of-labor principle, and then need to be integrated to create a unified percept. How this is done is still not clear. For instance, recent evidence showed crossmodal activation in primary areas. We developed a novel approach to study multisensory integration using multifrequency spectral analysis to investigate the processing of audio and visual streams in a multisensory context. Auditory and visual stimuli were delivered in the same experimental condition, each in different presentation frequencies, and thus could be detected by applying Fourier spectral analysis in their different presentation frequencies. The cochleotopic and retinotopic organization of primary auditory and visual areas were found to remain intact in spite of the multisensory context. Auditory responses were also found in the Precuneus, suggesting that it might be a new auditory area responsive to pure tone stimuli, and serving as one end of a novel sensory preference gradient stretching across POG to the calcarine sulcus. Additional audiovisual areal convergence was detected both in areas in the middle of sensory preference gradients, and in primary auditory areas. Interestingly, the in/out synchronization rate of the auditory and visual streams yielded a third interaction frequency, which could be analyzed independently to reveal higher-order audiovisual interaction responses. These results were detected in one compact and natural multisensory experimental condition, which has several advantages over previous approaches. The method can be further implemented to study any type of interaction, within and across sensory modalities. (C) 2010 Elsevier Inc. All rights reserved.