Processing Streams in the Cerebral Cortex

描述(申请人提供)：近年来，在理解涉及听觉感知和认知的皮质区域方面取得了很大进展。我们实验室和其他许多实验室的工作已经证明，在人类和非人类动物中都存在功能专门的加工流(参见Rauscheck ker，2012，以供审查)。腹侧的“What”流被证明参与了复杂声音的识别；背侧的“where”流被定义为专门处理空间和运动。上一个供资期间的工作集中于了解腹侧流的处理原理，并取得了许多成果(见进度报告)。即将到来的供资周期的工作重点将放在回流上。特别是，我们建议研究清醒恒河猴后上颞叶皮质(PST)内的听觉区域以及顶叶和运动前皮质中的听觉相关区域。根据先前的结果，我们预测PST和顶叶皮质的背侧流区域对空间位置具有特别的选择性。此外，还提出了背流功能在音频-运动控制和整合中的新的、更广泛的作用(Rauscheck ker，2011)。我们将通过训练猴子在一种特殊的行为设备(“猴子钢琴”)上产生声音序列来检验这一假设。然后，这些序列以及未经训练的控制序列将被用作功能磁共振成像(FMRI)研究中的听觉刺激，以及来自相同猴子的单/多单元记录。这项研究分为三个具体目标：目标1将使用功能磁共振成像和单/多单元记录研究尾带和副脑带(CB/CPB)区域的空间和时间特性的调节。空间运动的专门化将通过呈现模仿隐约可见的物体的刺激来测试。目标2和目标3将研究新提出的背侧流在音频-运动控制和整合中的作用：目标2将结合行为训练使用功能磁共振成像；目标3将使用来自多个站点的并行记录 多电极阵列(MEA)。通过测试与空间和音频-运动功能相关的特征在背流区的相对表征，我们将确定这些功能是在流的两个分支中相对独立地完成的，还是它们组合成一条整合的音频-空间-运动加工路径。我们的研究使用在行为任务中训练的警觉猴子，将有助于理解跨感觉系统的皮质功能的统一原则。它们将进一步加深我们对中风或阿尔茨海默病导致的人类感知和认知缺陷的理解，这些缺陷会导致视觉和听觉失认以及空间定向丧失。这些研究也与阅读障碍和自闭症等障碍有关，这些障碍包括语言理解或社交能力方面的问题。最后，了解颞叶和顶叶网络及其与额叶皮质的大量联系将为更高的神经和精神功能障碍，如注意力缺陷障碍和精神分裂症提供重要线索。

DESCRIPTION (provided by applicant): In recent years, great progress has been made in understanding cortical areas involved in auditory perception and cognition. Work from our laboratory as well as many others has demonstrated the existence of functionally specialized processing streams in both humans and nonhuman animals (see Rauschecker, 2012, for review). A ventral "what"-stream was shown to be involved in the identification of complex sounds; a dorsal "where"- stream was defined as specialized in processing space and motion. Work in the previous funding period has concentrated on understanding processing principles in the ventral stream and has produced numerous results (see Progress Report). Work in the upcoming funding cycle will focus on the dorsal stream. In particular, we propose to study auditory areas within posterior superior temporal cortex (pST) and auditory-related areas in parietal and premotor cortex of awake rhesus monkeys. Building on prior results, we predict that areas of the dorsal stream in pST and parietal cortex are particularly selective for spatial location. In addition, a new, expanded role for dorsal-stream function in audio-motor control and integration has been proposed (Rauschecker, 2011). We will test this hypothesis by training monkeys to produce sound sequences on a special-built behavioral apparatus ("monkey piano"). These sequences as well as untrained control sequences will then be used as auditory stimuli in functional magnetic resonance imaging (fMRI) studies and single-/multi- unit recordings from the same monkeys. The study is divided into three specific aims: Aim 1 will investigate tuning for spatial and temporal properties in areas of the caudal belt and parabelt (CB/CPB) using fMRI and single-/multi-unit recording. Specialization for motion-in-space will be tested by presenting stimuli mimicking looming objects. Aims 2 and 3 will study the newly proposed role of the dorsal stream in audio-motor control and integration: Aim 2 will utilize fMRI in combination with behavioral training; Aim 3 will use parallel recording from multiple sites with multi-electrode arrays (MEAs). By testing how features relevant to spatial and audio- motor functions are represented relative to each other in dorsal-stream areas, we will determine whether these functions are accomplished relatively independently in two branches of the stream, or whether they are combined into one integrated audio-spatio-motor processing pathway. Our studies, using alert monkeys trained in a behavioral task, will contribute to the understanding of unified principles of cortical function across sensory systems. They will further our understanding of deficits in human perception and cognition from stroke or Alzheimer's disease, which result in visual and auditory agnosia as well as loss of spatial orientation. The studies are also relevant for disorders such as dyslexia and autism, which include problems in language comprehension or ability for social communication. Finally, understanding temporal and parietal networks with their massive connections to frontal cortex will yield important clues about higher neurological and mental dysfunctions, such as attention-deficit disorder and schizophrenia.