The Functional Electrical Neuroimaging Laboratory, Department of Clinical Neurosciences, Vaudois University Hospital Center and University of Lausanne, Lausanne, Switzerland.
Neuroimage. 2012 Sep;62(3):1478-88. doi: 10.1016/j.neuroimage.2012.05.027. Epub 2012 May 18.
Multisensory experiences influence subsequent memory performance and brain responses. Studies have thus far concentrated on semantically congruent pairings, leaving unresolved the influence of stimulus pairing and memory sub-types. Here, we paired images with unique, meaningless sounds during a continuous recognition task to determine if purely episodic, single-trial multisensory experiences can incidentally impact subsequent visual object discrimination. Psychophysics and electrical neuroimaging analyses of visual evoked potentials (VEPs) compared responses to repeated images either paired or not with a meaningless sound during initial encounters. Recognition accuracy was significantly impaired for images initially presented as multisensory pairs and could not be explained in terms of differential attention or transfer of effects from encoding to retrieval. VEP modulations occurred at 100-130 ms and 270-310 ms and stemmed from topographic differences indicative of network configuration changes within the brain. Distributed source estimations localized the earlier effect to regions of the right posterior temporal gyrus (STG) and the later effect to regions of the middle temporal gyrus (MTG). Responses in these regions were stronger for images previously encountered as multisensory pairs. Only the later effect correlated with performance such that greater MTG activity in response to repeated visual stimuli was linked with greater performance decrements. The present findings suggest that brain networks involved in this discrimination may critically depend on whether multisensory events facilitate or impair later visual memory performance. More generally, the data support models whereby effects of multisensory interactions persist to incidentally affect subsequent behavior as well as visual processing during its initial stages.
多感官体验会影响后续的记忆表现和大脑反应。迄今为止，研究主要集中在语义一致的配对上，而刺激配对和记忆亚型的影响仍未得到解决。在这里，我们在连续识别任务中使用独特的、无意义的声音来配对图像，以确定纯粹的情景、单次多感官体验是否会偶然影响后续的视觉物体辨别。视觉诱发电位（VEPs）的心理物理学和电神经影像学分析比较了在初始接触时，重复呈现的图像与无意义声音配对或不配对时的反应。对于最初呈现为多感官对的图像，识别准确性显著下降，并且不能用注意力差异或从编码到检索的效果转移来解释。VEP 调制发生在 100-130ms 和 270-310ms 之间，源自拓扑差异，表明大脑内网络配置发生变化。分布式源估计将早期效应定位到右侧颞上回（STG）的区域，而晚期效应定位到中颞回（MTG）的区域。在这些区域中，对于先前作为多感官对遇到的图像，响应更强。只有晚期效应与表现相关，即对重复视觉刺激的 MTG 活动越大，表现下降越大。本研究结果表明，参与这种辨别过程的大脑网络可能取决于多感官事件是促进还是损害后续的视觉记忆表现。更一般地，数据支持这样的模型，即多感官相互作用的影响持续存在，以偶然影响后续行为以及初始阶段的视觉处理。
