Top-down control during selective listening in cocktail party situations

在日常生活中，听者经常面临由多个独立的声音流组成的复杂听觉环境。有选择地听这些流中的一个，同时不被竞争的听觉刺激分散注意力，这对我们的听觉系统来说是一个终极挑战。以前的工作已经令人信服地表明，注意过滤的信息发生在听觉系统内的感觉处理的不同层次，导致增加听觉皮层表示的关注流和抑制无关的信息。自愿控制注意力焦点和有选择地倾听任何感兴趣的声源的能力与额叶和顶叶大脑区域网络中的神经活动有关。然而，这两个处理水平在选择性听力过程中如何相互作用还没有完全了解。因此，在我计划在加拿大蒙特利尔的Robert Zatorre博士的实验室进行研究期间，我将研究听觉皮层中信息的注意门控与额顶叶注意网络在选择性听力过程中施加的目标导向自上而下控制之间的关系。脑磁图（MEG）将用于测量正常听众以及一组训练有素的专业音乐家在选择性听力任务期间的皮层活动。这些数据将在组水平上进行分析，并使用基于表现的受试者之间的方法来识别那些在具有挑战性的情况下成功选择性倾听所必需的大脑区域和功能连接。在第二步中，将使用高分辨率结构磁共振成像（MRI）和扩散张量成像（DTI）研究上级选择性听力能力的结构标记。

In daily life, listeners are often confronted with complex auditory environments consisting of multiple independent sound streams. Selectively listening to one of these streams, while not being distracted by the competing auditory stimulation, represents an ultimate challenge for our auditory system. Previous work has compellingly demonstrated that attentional filtering of information occurs at different levels of sensory processing within the auditory system, leading to both an increased auditory cortex representation of the attended stream and a suppression of irrelevant information. The ability to voluntarily control the focus of attention and to listen selectively to any sound source of interest has been linked to neural activity in a network of frontal and parietal brain regions. How these two processing levels interact during selective listening is however not fully understood. During my proposed research stay in the lab of Dr. Robert Zatorre in Montreal, Canada, I will therefore investigate the relationship between attentional gating of information in auditory cortex and goal-directed top-down control exerted by the fronto-parietal attention network during selective listening. Magnetoencephalography (MEG) will be used to measure cortical activity during a selective listening task in normal listeners as well as in a group of highly trained professional musicians. The data will be analyzed both on group-level and using performance-based between-subject approaches to identify those brain regions and functional connections essential for successful selective listening in challenging situations. In a second step, structural markers of superior selective listening abilities will be investigated using high resolution structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI).