Attention and Auditory Scene Analysis

听觉场景分析(ASA)是认知神经科学中的一个研究领域，它试图了解我们如何从到达我们耳朵的声音场景(即混合的声音波形)中感知和识别环境中的声音对象。到目前为止，ASA的研究主要集中在使用各种纯音配置的低水平特征驱动的过程上，而先验知识对ASA的影响相对较少受到关注。这给我们对听觉特征的理解留下了很大的空白，因为虽然我们可能怀疑图式驱动的过程在日常听觉环境的感知中发挥着重要作用，但我们还不知道先前的知识(即听觉图式)如何影响声音特征的分组。模式驱动的流程在什么情况下会影响功能驱动的流程？大脑如何处理不受注意的声音物体，这取决于先前的经验或预期吗？这些只是其中的几个问题，一旦得到回答，就会推动理论和培训计划，努力提高在不利听力条件下的听力技能。这项全面的研究计划包括一系列关于听觉注意和听觉感知的实验，重点是特征驱动的和图式驱动的视觉感知在音景感知过程中如何相互作用。我的工作假设是，图式驱动而不是特征驱动的ASA是音景知觉的主要决定因素。本研究的具体目标是：(I)表征特征驱动和图式驱动的声场效应之间的相互作用；(Ii)确定在什么条件下，当我们感知、注意到变化和识别先前听到的声景时，我们使用声景的局部和全局特性；(Iii)考察内隐学习对注意和声场效应的影响；(Iv)评估非自愿注意捕获如何影响特征和图式驱动的声场。所有研究将包括听力正常的成年人和神经电脑活动的测量，而参与者则被呈现在一个虚拟的听觉环境中。我们将使用熟悉和陌生的材料，并将操纵任务指令和声学参数，如音色和位置，以影响分离和识别不同的声音对象。这项研究将通过揭示图式驱动的ASA在什么条件下影响声音的频谱和时间属性如何结合在一起形成声音对象表征来促进注意理论和ASA理论的发展。确定特征驱动和图式驱动的ASA之间的平衡将有助于制定培训计划，以提高正常听力以及患有脑损伤、听力损失和其他医疗条件(如注意力调节和执行功能缺陷)的个人的听力技能。最后，这项研究将是变革性的，它证明了音景感知首先是由自上而下的过程指导的。

Auditory scene analysis (ASA) is an area of study in cognitive neuroscience that seeks to understand how we perceive and identify sound objects in the environment from the soundscape (i.e., a mixture of sound waveforms) that reaches our ears. To date, ASA research has primarily focused on low-level feature-driven processes using a wide range of pure tone configurations, whereas the influence of prior knowledge on ASA has received relatively little attention. This leaves a large gap in our understanding of ASA because, while we may suspect that schema-driven processes play a major role in perception of everyday auditory environments, we do not yet understand how prior knowledge (i.e., auditory schema) impacts the grouping of sound features. Under what conditions do schema-driven processes influence feature-driven processes? How does the brain deal with sound objects that fall outside of attention, and does this depend on prior experience or expectation? These are just a few of the questions that, when answered, will advance theories and training programs that strive to improve listening skills in adverse listening conditions. This comprehensive research program includes a series of experiments on auditory attention and ASA with an emphasis on how feature- and schema-driven ASA interact during soundscape perception. My working hypothesis is that schema-driven rather than feature-driven ASA is the primary determinant of soundscape perception. The specific aims of this research program are to: (i)characterize the interaction between feature- and schema-driven ASA; (ii)determine under which conditions we use local vs. global properties of a soundscape when we perceive, notice changes, and recognize previously heard soundscapes; (iii)examine the effect of implicit learning on attention and ASA; (iv)assess how involuntary attentional capture influences feature- and schema-driven ASA. All studies will include adults with normal hearing and measurements of neuroelectric brain activity while participants are presented with a virtual auditory environment. We will use familiar and unfamiliar material and will manipulate task instructions and acoustic parameters such as timbre and location to influence the separation and identification of distinct sound objects. The proposed research will advance theories of attention and ASA by revealing under what conditions schema-driven ASA influences how spectral and temporal properties of sounds are bound together into sound object representations. Determining the balance between feature- and schema-driven ASA will help to develop training programs targeted towards improving listening skills in normal hearing as well as individuals with brain damage, hearing loss, and other medical conditions such as deficits in attentional regulation and executive functions. Lastly, this research will be transformative by demonstrating that soundscape perception is first and foremost guided by top-down processes.