Effects of Emotion on Neural Encoding of Sound

描述（由申请人提供）：脑干的传统观点在将听觉信号传递到大脑的更高区域方面承担了静态和被动的角色，但最近的证据表明系统比以前认为的更具动态性和可塑性。在视觉系统中，有大量证据表明，面孔识别过程中存在平行的通路，大脑皮层中有一个高分辨率的系统，处理细粒度的数据，还有一个快速进化的古老通路，通往边缘系统，传递空间粗糙但高度生物相关的信息，如面部表情。在解剖学上，听觉脑干和边缘系统之间也存在着直接而广泛的联系，这些联系在啮齿动物和灵长类动物中也有解剖学上的特征。然而，这些连接没有功能特征。我们研究的重点是了解在听觉处理流的最早阶段，声音的神经表征如何受到情绪刺激（如唤起情绪的图像）的影响，并定义整个听觉通路中这种相互作用的增长和转变。我们感兴趣的是如何确定一个听众的情绪状态，引起情绪唤起视觉刺激，影响听众的生理反应的讲话。为此，在使用来自情绪视觉刺激的标准化数据库的图像在听者中诱导三种情绪状态（包括“中性”状态）之后测量对听觉语音的生理反应。远场和近场记录（分别为脑干和皮层反应）将评估皮层下和皮层过程对两种输入模式相互作用的相对贡献，并阐明相互作用的时间。我们的初步数据显示，情绪状况之间存在统计学上的显著差异。我们目前知道，脑干的可塑性比以前想象的要大得多，这为治疗疾病的潜在效果以及增强语言和音乐学习的潜力提供了希望，但这种可塑性还有其他方面。众所周知，焦虑症与抑郁症有很高的共病率，情绪健康与一般心理健康有很大的互动性。如果脑干在小时的时间尺度上是可塑的，那么我们就有理由相信焦虑症不仅会影响一个人的情绪健康，还会在非常基本的水平上对感觉处理产生不利影响。

DESCRIPTION (provided by applicant): Traditional views of the brainstem have assumed a static and passive role in relaying the auditory signal to higher regions of the brain, but recent evidence indicates a far more dynamic and malleable system than previously thought. In the visual system, there is a plethora of evidence pointing to parallel pathways in the recognition of faces, a high-resolution system in the cortex that processes fine-grained data, and a fast, evolutionary ancient pathway to the limbic system that relays spatially coarse but highly biologically relevant information like facial expression. Anatomically, there is known to be direct and widespread connections between the auditory brainstem and the limbic system as well, and these have been characterized, anatomically, in rodents and primates. However, these connections have not been functionally characterized. The focus of our research is to understand how the neural representation of sounds is affected by emotional stimuli, such as emotion-evoking images, at the earliest stages of the auditory processing stream and to define the growth and transformation of this interaction throughout the auditory pathway. We are interested in determining how a listener's emotional state, induced by emotion-evoking visual stimuli, influences the listener's physiological response to speech. To do this, physiological responses to auditory speech are measured after inducing three emotional states (including a "neutral" state) in the listener with the use of images from a standardized database of emotional visual stimuli. Far-field and near-field recordings (brainstem and cortical responses, respectively) will assess the relative contributions of subcortical and cortical processes to the interaction of the two input modes and illuminate timing of the interactions. Our preliminary data show statistically significant differences between emotional conditions. We currently know that the brainstem is far more malleable than previously thought, which gives promise to the potential effects of therapies for disorders as well as the potential to enhance the learning of language and music, but there are other aspects to this malleability as well. It is known that anxiety disorders have a high comorbidity with depression, and that emotional health is hugely interactive with general mental health. If the brainstem is malleable on the time-scale of hours, it is reasonable to believe that anxiety disorders not only influence one's emotional health, it can also adversely affect sensory processing at a very basic level.