Physiological Correlates And Neural Mechanisms Of Vocal

Z01 HD 001123 LCE和Z01 HD 001124 LCE是共同研究灵长类听觉交流的伙伴项目。这些研究的总体目标是从发育、神经机制、内分泌因素和社会背景等方面全面了解灵长类听觉交流。两种非人类灵长类动物，松鼠猴和普通绒猴是主要的研究对象，并在适当的情况下从其他物种收集额外的数据。该项目先前的工作表明，婴儿哭声的功能和声学等价物的产生是由位于大脑皮层额叶前中线的边缘皮质调节的，听觉皮质中的单个神经元件(颞上回)对物种特定发声的声学结构中的细微差异特别敏感，这表明在调节个体差异(声音特征)方面发挥着重要作用。今年的新发现：c-fos基因及其蛋白产物Fos被用来标记在一段时间的强烈行为活动后活动增加的神经区域。对c-fos在成年松鼠猴脑中的表达进行了研究。这一范式包括将个体分开30分钟，记录隔离呼叫？在分离过程中，将它们放回家笼子里1小时，然后对它们实施安乐死，并使用免疫细胞化学对它们固定的大脑进行Fos处理。使用了6个人，3个发声良好的人和3个发声不佳的人(30分钟内呼叫少于10次)。200倍的显微照片被数字化，然后对标记的细胞进行计数。我们比较了发声能力好和发声能力差的人的3个脑区的视野。这3个区域分别是扣带回前部、脑室旁/中脑导水管周围灰质和丘脑背内侧。前两个是在一项使用大脑损伤的研究中发现的，它与分离的松鼠猴子的叫声表达有关；最后一个已知是前扣带回的投射区域，但没有包括在早期的研究中。发声能力好的和发声能力差的人的大脑三个区域的标记细胞计数有显著差异。在所有情况下，发声好的人的数量都更高。这些结果表明，c-fos免疫细胞化学是一种有效的替代方法，可以显示灵长类动物发声所涉及的脑区的功能，并且具有在单个动物中标记整个神经轴的结构的优势，而更古老的技术，如损伤，需要更多的动物才能给出明确的结果。在第二项研究中，开发了一种创建大脑示意图的新方法，作为为普通绒猴创建脑图谱的一部分。使用Adobe Photoshop将一只成年雌性绒猴的额部数字照片设置为标准尺寸。这些图像随后被导入到美国国立卫生研究院开发的程序ImageJ中。通过反转图像并使用？查找边？工具，创建了图像的轮廓版本。这些示意图图像的内部结构仍然可以被识别和标记。这允许保留原始数字照片，而不会分散任何附加标签的注意力。与此同时，可以在示意图中识别大脑部分内的个别结构，使未来的图集用户能够在给定的大脑部分找到自己的路。这项工作是由蒙哥马利布莱尔高中的学生雷切尔·贝尔女士在UNE和NINDS的Afonso Silva博士的合作下完成的。

Z01 HD 001123 LCE and Z01 HD 001124 LCE are companion projects that together investigate auditory communication in primates. The overall goal of these studies is to provide a comprehensive understanding of primate auditory communication in terms of development, neural mechanisms, endocrine factors, and social context. Two non-human primates, the squirrel monkey and common marmoset, are the main subjects of study, with additional data collected from other species where appropriate. Prior work in this project has shown that production of sounds that are the functional and acoustic equivalents of cry sounds in human infants are mediated by limbic cortex located along the anterior midline of the frontal lobe of the cerebral cortex, and that single neural elements in the auditory cortex (superior temporal gyrus) are particularly responsive to subtle differences in the acoustic structure of species-specific vocalizations, suggesting an important role in mediating individual differences (vocal signatures). New findings this year: The gene c-fos and its protein product Fos, have been used to mark neural regions of increased activity following a period of robust behavioral activity. A study of c-fos expression in adult squirrel monkey brains was conducted. The paradigm involved separating individuals for 30 minutes, recording the ?isolation calls? made during this separation, returning them to their home cage for 1 hour, then euthanizing them and processing their fixed brains for Fos using immunocytochemistry. Six individuals were used, 3 good vocalizers and 3 poor vocalizers (less than 10 calls in 30 minutes). Microphotographs at 200 magnifications were digitized, then labelled cells counted. Fields from 3 brain areas were compared between good vocalizers and poor vocalizers. The 3 areas were the anterior cingulate gyrus, the perventricular/periaqueductal gray, and the dorsomedial thalamus. The first 2 were found in a study using brain lesioning to be involved in expression of calls in separated squirrel monkeys; the last is known to be a projection area to the anterior cingulate, but was not included in the earlier study. Counts of labelled cells were significantly different between all 3 areas in the brains of good and poor vocalizers. In all cases, counts were higher in the good vocalizers. These results indicate that c-fos immunocytochemistry is a valid alternative to demonstrating the functional involvement of primate brain regions involved in vocalizing, and has the advantage of labelling structures throughout the neuraxis in a single animal, whereas older techniques such as lesioning require many more animals to give a clear result. In a second study, a new method for creating schematic brain images was developed as part of the creation of a brain atlas for the common marmoset. Digital photographs of frontal sections from an adult female marmoset were set to a standard size using Adobe Photoshop. The images were then imported into ImageJ, a program developed at the NIH. By inverting the image and using the ?find edges? tool, an outline version of the image was created. The internal structure of these schematic images could still be discerned and labelled. This permitted retention of the original digital photograph, without the distraction of any added labels. At the same time, individual structures within the brain section could be identified in the schematic image, allowing future users of the atlas to find their way around a given brain section. This work was done by Ms. Rachel Bell, a student at Montgomery Blair High School, in a collaboration between the UNE and Dr. Afonso Silva of the NINDS.