A new laboratory to study brain dynamics of soundscape in virtual environment

我们的听觉环境是由许多声源组成的（例如风吹动附近树叶的声音、狗叫声和汽车驶过的声音）。来自我们周围每一个声源的声能加在一起形成一个单一的声波进入耳朵。大脑是如何设法理解这一单一的复合波的，这样我们就可以解构它，感知和识别这三个独立的听觉对象？从完形心理学中借用的一个突出理论是听觉场景分析：音调和位置相似的声音，并且一起“移动”，可能来自同一个物理对象。虽然这一理论在实验室中预测非常简单的声音的结果时效果相当不错，但它尚未在更复杂和真实的声音环境中进行测试。先前的知识已被证明有助于在不利的嘈杂环境中感知和识别熟悉的声音或旋律。先验知识如何影响基于声学线索的分组？在听觉场景分析中，先验知识、注意力和自动化过程是如何相互作用的？这些问题的提出将促进听觉感知理论和训练计划，以提高听力技能在不利的听力条件下，特别是对听力困难的人群。 我们希望通过使用更符合生态学的刺激来收集数据，以测试当前听觉感知理论的局限性。为了实现这一点，我们需要一个工作站，可以操作几个音频通道，允许用户混合不同的环境声音，并以数字方式创建不同声波的混合物（即，音景）的特定环境（例如，多伦多的环境城市音景）。这个工作站将允许Baycrest中心的大脑健康和衰老专家在一个控制良好的实验室环境中使用沉浸式虚拟技术来拼凑大脑如何计算音景。 这样一个新颖的工作站，能够创造受控的，但更生态有效的听觉环境将（1）进一步加强在Baycrest中心的听觉认知研究的势头;（2）支持正在进行的和未来的合作，在听觉场景分析领域，（3）最终推进我们对听力之间的联系的理解，我们如何理解和与我们的环境互动。这项新兴技术将为学生提供特殊和独特的培训机会。在实验室工作的学员将获得一套适用于认知神经科学和实验心理学等领域的学术职业或私营部门的职业生涯（如声音工程和虚拟/增强现实）的市场技能（如编码，批判性思维，写作，公开演讲）。

Our auditory environment is comprised of many sound sources (such as the wind rustling the leaves of the trees nearby, a dog barking, and a car driving by). Acoustic energy from every sound source in our surroundings sum together to form a single soundwave that enters the ear. How does the brain manage to make sense of that single composite wave, such that we can deconstruct it and perceive and identify these three separate auditory objects? One prominent theory borrowed from Gestalt psychology is that of auditory scene analysis: sounds that are similar in pitch and location, and that “move” together, are likely to originate from the same physical object. While this theory works reasonably well in predicting the outcome of very simple sounds in the laboratory, it has not been tested in more complex and real-world sound settings. Prior knowledge has been shown to facilitate the perception and recognition of a familiar voice or melody in adverse noisy environments. How does prior knowledge impact the grouping based on acoustic cues? How does prior knowledge, attention, and automatic processes interact with one another during auditory scene analysis? Answering these questions will advance theories of auditory perception and training programs for improving listening skills in adverse listening conditions, especially for populations with hearing difficulties. We want to test the limits of current theories of auditory perception by collecting data using more ecologically valid stimuli. To accomplish this, we need a workstation that can operate several audio channels, allowing users to mix different environmental sounds and to digitally create a mixture of different soundwaves (i.e., soundscapes) of a particular environment (e.g., ambient city soundscapes in Toronto). This workstation will allow brain health and aging experts at Baycrest Centre to use immersive virtual technology in a well-controlled lab setting to piece together how the brain figures out soundscapes. Such a novel workstation capable of creating controlled yet more ecologically valid auditory environments will (1) further enhance the momentum of auditory cognitive research at Baycrest Centre; (2) support ongoing and future collaborations in the area of auditory scene analysis, and (3) ultimately advance our understanding of links between hearing and how we understand and interact with our environment. This new and emerging technology will provide exceptional and unique training opportunities for students. Trainees working in the lab will gain a set of marketable skills (such as coding, critical thinking, writing, public speaking) applicable for academic careers in fields such as cognitive neuroscience and experimental psychology, or careers in the private sector such as in sound engineering and virtual/augmented reality.