Supramodal human brain networks for temporal frequency processing

项目摘要/摘要 时间频率是对我们如何通信至关重要的基本感觉域(例如， 通过听觉进行语音处理)，并与我们环境中的对象进行交互(通过触摸进行纹理处理)。我们的 听觉和触觉感觉冗余地向时间频率发出信号，每个周期跨越数十到数百个周期 第二。这种重叠使试听和触摸能够互动，这可能是有益的，因为信息 通过组合独立的感官提示提供的信息比通过单一的 感官提示。尽管有这样的背景，但我们对两者之间的关系并没有清楚的认识 听觉和触觉频率处理机制。神经基质的研究进展 传统上，支持试听和触摸都集中在单一的感官通道上。在这里我们将测试 假设共同的大脑区域和神经机制，称为超模式，支持听觉和 触觉频率处理。我们将开发一个感觉神经元如何结合的计算模型 听觉和触觉频率信息，以及这些神经元如何通过适应而改变。我们会 将该模型的预测与人类心理物理实验中获得的行为数据进行比较。vbl.使用 血氧水平依赖功能磁共振成像(BOLD FMRI)和感觉适应， 我们将定位反应模式与神经适应一致的大脑区域，我们将使用 这种测试大脑区域是否同时代表(即，适应)听觉和触觉频率的方法 信息。使用功能磁共振成像和多变量模式分析(MVPA)，我们将识别大脑中 可以对听觉和触觉频率信息进行解码。我们将确定各地区是否支持 两种感官的可解码频率表示法。我们的初步建模、心理物理学和成像 结果表明，坐骨神经周围皮质的多个区域，包括经典定义为单峰的区域， 显示对听觉和触觉刺激的频率选择性反应。这一模式表明 周边区可以作为频率处理的超模式网络。我们假设人们的注意力 振动频率增强了该频率网络中的功能连通性。我们将进行因果调查 经颅磁联合体感皮层与听觉皮层的功能连接 FMRI刺激(TMS)(同时进行TMS-fMRI实验)和行为(在心理物理实验中 实验)。根据我们的假设，我们预测躯体感觉TMS引起的神经变化 当受试者注意到振动频率时，皮层应该传播到听觉皮质。这一传播 应该调节听觉皮质活动和听觉知觉。这些预测结果将支持 经典定义的躯体感觉和听觉区域协同处理时间频率的概念 信息是一种超模式网络。超模式网络可能支持其他基本感觉 形状和动作处理等操作。

PROJECT SUMMARY/ABSTRACT Temporal frequency is a fundamental sensory domain that is critically important to how we communicate (e.g., speech processing by audition) and interact with objects in our environment (texture processing by touch). Our auditory and tactile senses redundantly signal temporal frequencies spanning tens to hundreds of cycles per second. This overlap enables audition and touch to interact, which can be beneficial because the information available by combining across independent sensory cues is more accurate than that provided by a single sensory cue. Despite this background, we do not have a clear understanding of the relationship between auditory and tactile frequency processing mechanisms. Previous investigations of the neural substrates supporting audition and touch have traditionally focused on a single sensory modality. Here we will test the hypothesis that common brain regions and neural mechanisms, termed supramodal, support auditory and tactile frequency processing. We will develop a computational model of how sensory neurons may combine auditory and tactile frequency information and how these neurons may be changed by adaptation. We will compare the model's predictions to behavioral data acquired in human psychophysical experiments. Using blood oxygen-level dependent functional magnetic resonance imaging (BOLD fMRI) and sensory adaptation, we will localize brain regions whose response patterns are consistent with neural adaptation, and we will use this approach to test whether brain regions represent (i.e., adapt to) both auditory and tactile frequency information. Using fMRI and multivariate pattern analysis (MVPA), we will identify the brain regions from which auditory and tactile frequency information can be decoded. We will determine whether regions support decodable frequency representations for both senses. Our preliminary modeling, psychophysics, and imaging results suggest that multiple regions in perisylvian cortex, including areas classically defined as unimodal, display frequency-selective responses to both auditory and tactile stimulation. This pattern suggests that perisylvian areas may serve as a supramodal network for frequency processing. We hypothesize that attention to vibration frequency enhances the functional connectivity in this frequency network. We will causally probe functional connectivity between somatosensory cortex and auditory cortex by combining transcranial magnetic stimulation (TMS) with fMRI (in concurrent TMS-fMRI experiments) and behavior (in psychophysical experiments). According to our hypothesis, we predict that neural changes caused by TMS of somatosensory cortex should propagate to auditory cortex when subjects attend to vibration frequency. This propagation should modulate auditory cortex activity and auditory perception. These predicted results would support the notion that classically defined somatosensory and auditory areas collaborate to process temporal frequency information as a supramodal network. Supramodal networks may support other fundamental sensory operations like shape and motion processing.