Distinguishing excitatory and inhibitory transcallosal interactions.

区分兴奋性和抑制性经胼胝体相互作用。

• 批准号: RGPIN-2019-06515
• 负责人: Meltzer, Jed
• 金额: $ 2.04万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=764260
• 关键词: Distinguishing; excitatory; inhibitory; transcallosal; interactions.

The human brain is divided into two halves, or hemispheres, which interact with each other to process information and control the body. A large amount of research has characterized the ways in which the two hemispheres are specialized. For example, the left hemisphere is dominant for language functions, while the right is superior at spatial judgments. However, most human cognition requires contributions from both hemispheres, and they communicate with each other in ways that are partially cooperative and partially competitive. Understanding how this communication happens between hemispheres is critical for the development of new methods to modulate brain activity in beneficial ways, such as through noninvasive brain stimulation. Recently, many new methods have been developed to detect the brain's electrical activity with a machine called magnetoencephalography (MEG). MEG records the electromagnetic waves generated by neurons with high spatial and temporal precision. By analyzing the activity in two brain regions simultaneously, researchers can examine the degree to which information is transferred between them at different times, and in which direction. Our laboratory's studies have suggested that it may be possible to distinguish cooperative and competitive interactions, which may manifest in different brain signals. To validate the analysis of these signals, we will take advantage of some well-known asymmetries of the brain, in which information is transferred from brain hemisphere to the other (a cooperative interaction), and in which one hemisphere suppresses the other (competition). For example, the left motor cortex controls the right side of the body, and the right motor cortex controls the left side of the body. When someone moves their right hand, their left motor cortex sends an excitatory signal to the right hand via the spinal cord, but also sends an inhibitory signal to the right motor cortex to prevent it from interfering. By measuring electrical activity during hand movements, and comparing it with other known measures of competition, we will validate the use of new techniques to detect competitive interactions. Another asymmetry occurs with peripheral vision. The left side of the brain receives visual information from the right visual field, and vice versa. Because the left hemisphere is dominant for language, information about words presented in the left visual field (to the right hemisphere) must be transferred to the left hemisphere, but the reverse occurs much less. On the other hand, the right hemisphere is dominant for making decisions about faces, so information about faces presented to the right visual field (left hemisphere) is differentially routed to the right hemisphere. By comparing interactions for words and faces, we will validate the use of new techniques to detect asymmetrical transfer of information between the hemispheres.

人脑分为两个半球，它们相互作用来处理信息并控制身体。大量研究已经描述了两个半球的专门化方式。例如，左半球在语言功能方面占主导地位，而右半球在空间判断方面占优势。然而，大多数人类认知需要两个半球的贡献，并且它们以部分合作、部分竞争的方式相互交流。了解半球之间的这种交流如何发生对于开发以有益的方式调节大脑活动的新方法至关重要，例如通过非侵入性大脑刺激。 最近，人们开发了许多新方法来使用脑磁图（MEG）机器来检测大脑的电活动。 MEG 以高空间和时间精度记录神经元产生的电磁波。通过同时分析两个大脑区域的活动，研究人员可以检查不同时间信息在它们之间传输的程度和方向。我们实验室的研究表明，区分合作性和竞争性互动是可能的，这可能体现在不同的大脑信号中。 为了验证这些信号的分析，我们将利用一些众所周知的大脑不对称性，其中信息从大脑半球转移到另一个半球（合作交互），并且其中一个半球抑制另一个半球（竞争）。例如，左运动皮层控制身体的右侧，右运动皮层控制身体的左侧。当有人移动右手时，左运动皮层会通过脊髓向右手发送兴奋信号，同时也会向右运动皮层发送抑制信号以防止其干扰。通过测量手部运动期间的电活动，并将其与其他已知的竞争措施进行比较，我们将验证新技术的使用来检测竞争性相互作用。 另一种不对称现象发生在周边视觉上。大脑的左侧从右侧视野接收视觉信息，反之亦然。由于左半球在语言方面占主导地位，因此左视野（右半球）中呈现的单词信息必须转移到左半球，但相反的情况则少得多。另一方面，右半球在做出有关面部的决策时占主导地位，因此呈现给右视野（左半球）的有关面部的信息会被不同地路由到右半球。通过比较单词和面部的交互，我们将验证新技术的使用来检测半球之间的不对称信息传输。