Neuronal Correlates of the Visual Modulation of Auditory Performance

描述（由申请人提供）：在自然环境中，大脑经常面临着解释在存在噪声的情况下发生的听觉信号的艰巨任务，这会使重要的听觉事件变得模糊和不那么突出。然而，在自然主义的情况下，这些听觉线索通常伴随着视觉信息，通常来自相同的事件。这种一致的视听线索的存在可以极大地放大感兴趣的刺激的显著性。然而，尽管许多研究已经说明了具有多感官的行为和感知益处（例如，视听）线索，以及越来越多的文献对神经编码过程的特点多感觉的相互作用，很少有研究能够链接多感觉神经的变化，他们的行为和感知相关。为了更牢固地建立这些联系，我们将训练恒河猴检测或定位目标声音（信号），并忽略正在进行或同时发生的非目标声音（噪音）。将改变信号和噪声之间的空间和时间关系，以评估它们对猴子检测或定位信号的影响。类似的实验将在添加视觉刺激的情况下进行，视觉刺激的位置和/或定时将变化，使得其有时匹配信号的位置和/或定时，有时匹配噪声的位置和/或定时。这将使我们能够评估非听觉（视觉）刺激对听觉行为表现的影响，并使我们能够评估多感觉整合的大脑机制。下丘和上级神经元的神经生理学记录有望揭示其在听觉和视听检测和定位行为中的不同作用。这项工作的翻译和临床相关性对于听力受损者和老年人来说非常高，因为听觉辅助设备在嘈杂的环境中通常表现不佳。更多地了解大脑如何在噪声中处理听觉信号，以及视觉信息如何在复杂环境中增强神经和行为表现，将有助于设计更好的技术来应对听力损失及其对生活质量的深远影响。

DESCRIPTION (provided by applicant): In the natural environment, the brain is often confronted with the daunting task of interpreting auditory signals that occur in the presence of noise, which can render important auditory events ambiguous and less salient. However, in naturalistic circumstances these auditory cues are typically accompanied by visual information, often from the same events. The presence of such coincident audiovisual cues can greatly amplify the salience of a stimulus of interest. However, although a number of studies have illustrated the behavioral and perceptual benefits of having multisensory (e.g., audiovisual) cues available, and a growing literature on the neural encoding processes that characterize multisensory interactions, very few studies have been able to link multisensory neural changes to their behavioral and perceptual correlates. To more firmly establish these links, we will train rhesus monkeys to detect or localize a target sound (signal), and ignore ongoing or simultaneously occurring non-target sounds (noise). The spatial and temporal relationships between the signal and noise will be varied, to evaluate their effects on how well the monkey detects or localizes the signal. Similar experiments will be performed with the addition of visual stimuli, whose location and/or timing will be varied such that it sometimes matches that of the signal, and sometimes that of the noise. This will allow us to assess the effects of non-auditory (visual) stimuli on auditory behavioral performance and allow us to evaluate brain mechanisms of multisensory integration. Neurophysiological recordings of neurons in the inferior and superior colliculi are expected to reveal their differential role in auditory and audiovisual detection and localization behaviors. The translational and clinical relevance of this work is very high for the hearing impaired and the elderly, in that auditory assistive devices often perform poorly in noisy environments. Greater knowledge of how the brain processes auditory signals within noise, and how visual information can enhance neural and behavior performance in complex environments, will be of great utility for the design of better technologies to deal with hearing loss and its profound impact on quality of life.