Attentional Mechanisms in Multisensory Environments

描述（由申请人提供）：我们生活在一个多感官的世界，这需要我们不断地，动态地，有效地处理来自各种感官形式的刺激。为了成功地做到这一点，我们需要将相应的单感官刺激成分整合在一起，以感知连贯的多感官对象，同时也要适当地隔离并发的非对应刺激。在下一个阶段的补助金，我们提出了一套新的研究，继续我们的机制，注意力和相关的认知因素，促进在复杂的多感官环境中的有效运作的程序调查。在 特别是，我们将研究这些机制的三个基本方面。首先，我们将研究空间注意和奖赏前景的自上而下的认知因素对多感觉（听觉/视觉）整合和分离过程的影响。其次，我们将研究复杂刺激环境中快速注意目标搜索过程的机制在听觉和视觉模态中的共性，包括这种注意过程的跨模态耦合。第三，我们将调查多感觉整合和分离过程时，从一个特定的通道输入是相关的，但有冲突的并发输入从第二个通道，我们还将比较这些跨通道的过程中调用的冲突输入从同一个通道。 和以前一样，我们将使用行为测量、振荡脑电图（EEG）、事件相关电位（ERP）和功能性MRI（fMRI）的组合来进行这些研究，目的是描绘潜在神经过程的时间、顺序和位置。此外，我们将获得脑电图和功能磁共振成像测量大脑活动的同时，为几个拟议的实验使用我们的新的MR兼容脑电图系统购买通过补充从这个项目。这种方法将使我们能够对EEG和fMRI数据模式进行试验到试验的协变分析，提供强大的新方法将高时间分辨率EEG信号与fMRI中测量的相关皮层发生器联系起来。此外，同步记录还将使我们能够检查对皮质EEG的调节影响，这些皮质下脑区涉及注意力、奖励和多感觉整合，但其影响无法单独用EEG评估。因此，这些实验将以前所未有的精确度描绘出神经机制，通过这些机制，注意力和相关的认知功能能够成功地导航我们复杂的多感官世界。

DESCRIPTION (provided by applicant): We live in a multisensory world, which requires us to continually, dynamically, and effectively process stimuli from across the sensory modalities. To do so successfully, we need to integrate corresponding unisensory stimulus components together to perceive coherent multisensory objects, while also appropriately segregating out concurrent non-corresponding stimuli. In the next period of this grant, we propose a new set of studies to continue our programmatic investigation of the mechanisms by which attention and related cognitive factors facilitate effective functioning in complex multisensory environments. In particular, we will investigate three fundamental facets of these mechanisms. First, we will study the influence of the top-down cognitive factors of spatial attention and reward prospect on multisensory (auditory/visual) integration and segregation processes. Second, we will examine the commonality across the auditory and visual modalities of the mechanisms underlying rapid attentional target-search processes in complex stimulus environments, including the cross- modality coupling of such attentional processes. Third, we will investigate the multisensory integration and segregation processes when input from one particular modality is relevant, but there is conflicting concurrent input from a second modality; we will also compare these crossmodal processes to those invoked in response to conflicting input from within the same modality. As before, we will use a combination of behavioral measures, oscillatory electroencephalography (EEG), event-related potentials (ERPs), and functional MRI (fMRI) to perform these studies, with the aim to delineate the timing, sequence, and location of underlying neural processes. Additionally, we will acquire EEG and fMRI measures of brain activity simultaneously for several of the proposed experiments using our new MR- compatible EEG system purchased via a supplement from this project. Such an approach will enable us to perform trial-to-trial covariational analyses on the EEG and fMRI data patterns, providing powerful new ways to link the high-temporal-resolution EEG signals to the associated cortical generators measured in the fMRI. Moreover, the simultaneous recording will also allow us to examine the modulating influence on the cortical EEG of the subcortical brain regions involved in attention, reward, and multisensory integration but whose influence cannot be assessed with EEG alone. Thus, these experiments will delineate with unprecedented precision the neural mechanisms by which attention and related cognitive functions enable successful navigation of our complex multisensory world.