Does the brain speed up when we move?

传统上，大脑被分为感觉部分和运动部分。感官部分--与视觉、听觉或触觉有关--向动物提供有关外部世界的信息。马达部分控制肌肉，并允许动物在那个世界中移动。然而，令人惊讶的是，现在很明显，大脑感觉部分的活动也可以受到自我运动的影响。这些感觉活动变化的目的尚不清楚。在这个提案中，我们将检验这样一个假设，即这些变化允许在自我运动过程中更好、更快地处理感觉信号。与静坐时相比，自我运动改变了提供给大脑的感觉输入的模式。例如，过马路会导致光线照射眼睛的模式发生巨大而频繁的变化。因此，在自我运动过程中，大脑必须应对感觉信号变化速度加快的问题。感觉通路如何能够适应这种增加的比率是未知的，也是我们研究计划的重点。我们将通过测量大脑视觉通路中的视觉反应来回答这个问题。我们将使用啮齿动物(老鼠)作为模型系统，在那里所需的实验技术已经建立得很好。我们将在动物静止和进行自我运动时测量视觉反应。我们将描述大脑活动的幅度和动态，在单个神经细胞水平上，在局部大脑回路水平上，在大脑系统水平上。利用我们帮助开创的实验和计算技术的最新进展，我们将测量眼睛输出的活动，眼睛的两个主要目标，以及大脑皮层处理视觉信号的主要区域。因此，我们的测量将显示自我运动如何改变神经细胞对视觉输入的反应速度，它如何改变视觉大脑区域之间的交流，以及这些神经变化如何帮助动物看到快速变化的视觉场景。这一建议很重要，因为现代生活方式与减少体力活动和增加久坐行为有关。众所周知，积极的生活方式可以改善正常衰老，并对大脑功能和心理健康产生积极影响，包括提高注意力和降低抑郁症的发生率。之前的大多数研究都集中在体力活动如何导致大脑结构的变化上，尚不清楚自我运动是否也有益于大脑功能。除了揭示感觉通路中与运动相关的活动的目的外，拟议的工作还可能有助于全面理解体育活动如何以及为什么影响大脑功能，并有助于终身健康。它还可能指导开发新的方法来改善视力障碍患者的功能，或改善治疗。

The brain is traditionally divided into sensory and motor parts. The sensory parts - concerned with sight, hearing, or touch - inform an animal about the outside world. The motor parts control the muscles, and allow the animal to move through that world. Surprisingly, however, it is now clear that activity in sensory parts of the brain can also be influenced by self-movement. The purpose of these changes in sensory activity is not known. In this proposal we will test the hypothesis that these changes allow better and faster processing of sensory signals during self-movement. Self-movement changes the patterns of sensory inputs provided to the brain compared to when sitting still. For example, crossing the road induces large and frequent changes in the patterns of light hitting the eye. During self-movement, therefore, the brain must contend with an increased rate of change in sensory signals. How sensory pathways are able to adapt to this increased rate is unknown, and is the focus of our research proposal.We will answer this question by measuring visual responses in the visual pathway of the brain. We will use rodents (mice) as a model system, where the required experimental techniques are well-established. We will measure visual responses while the animal is still, and while it is engaging in self-movement. We will characterise the amplitude and dynamics of brain activity, at the level of single nerve cells, at the level of local brain circuits, and at the level of brain systems. Exploiting recent advances in experimental and computational techniques, which we have helped pioneer, we will measure activity in the output of the eye, the two major targets of the eye, and major areas in the cerebral cortex that process visual signals. Our measurements will therefore show how self-movement changes the speed at which nerve cells react to visual input, how it changes the communication between visual brain areas, and how these neural changes help an animal to see rapidly changing visual scenes. This proposal is important because modern lifestyles are associated with decreased physical activity and increased sedentary behaviour. Active lifestyles are known to improve normal ageing, and have a positive impact on brain function and mental health, including increased attentional capacity and lower incidence of depression. Most previous research has focused on how physical activity leads to changes in the structure of the brain, and it is not known if self-movement also benefits brain function. As well as shedding light on the purpose of movement-related activity in sensory pathways, the proposed work may also help the general understanding of how and why physical activity influences brain function, and contributes to lifelong health. It may also guide the development of new approaches to improving function, or improving therapy, for people with visual disorders.