Naghavi Hamid Reza, Eriksson Johan, Larsson Anne, Nyberg Lars
Tehran University of Medical Sciences, Tehran, Iran.
Neurosci Lett. 2007 Jul 5;422(1):77-80. doi: 10.1016/j.neulet.2007.06.009. Epub 2007 Jun 14.
The brain is able to create coherent percepts from multisensory input. This phenomenon, known as multisensory integration (MSI), is a ubiquitous feature of everyday life and has been found to be essential for a reliable interaction with the environment. Recent functional neuroimaging studies suggest that several different networks are engaged in various forms of MSI depending on the nature of information being integrated. However, little is known about the neural basis of a fundamental form of MSI in natural conditions; integration of common auditory and visual objects which are conceptually related, such as when we look at a cat and hear a meowing sound. Here we used event-related fMRI to compare the brain response to conceptually related and unrelated pairs of audio-visual stimuli denoting common objects. Our protocol was designed to preclude contamination of the results by cognitive processes additional to those needed for MSI. The results indicate that higher-order temporal and occipital areas respond to coincident sounds and pictures regardless of their semantic relationship; whereas, the right claustrum/insula region is differentially activated in association with multisensory integration of conceptually related common objects. This observation has important implications for understanding how multimodal information about common objects is represented in the brain.
大脑能够从多感官输入中创建连贯的感知。这种现象，即多感官整合（MSI），是日常生活中普遍存在的特征，并且已被发现对于与环境进行可靠交互至关重要。最近的功能神经成像研究表明，根据所整合信息的性质，几种不同的神经网络参与了各种形式的多感官整合。然而，对于自然条件下多感官整合的一种基本形式的神经基础知之甚少；即整合概念上相关的常见听觉和视觉对象，例如当我们看着一只猫并听到喵喵声时。在这里，我们使用事件相关功能磁共振成像来比较大脑对表示常见对象的概念相关和不相关视听刺激对的反应。我们的实验方案旨在排除除多感官整合所需的认知过程之外的其他认知过程对结果的干扰。结果表明，无论语义关系如何，高阶颞叶和枕叶区域都会对同时出现的声音和图片做出反应；然而，右侧屏状核/脑岛区域在与概念相关的常见对象的多感官整合相关时会有差异地被激活。这一观察结果对于理解大脑中如何表示关于常见对象的多模态信息具有重要意义。
