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  • 中央神经系统

    The human brain . The "control center." What does it control?
    ::人脑,"控制中心" 它能控制什么?

    Practically everything. From and heartbeat to reasoning, memory, and language. And it is the main part of the central nervous system.
    ::几乎所有的东西,从心跳到理性、记忆和语言, 并且是中枢神经系统的主要部分。

    The Central Nervous System
    ::中央神经系统

    The central nervous system (CNS), which includes the brain and the spinal cord (see  Figure ), represents the largest part of the . The brain is the central control of the nervous system, and the spinal cord acts as a superhighway, carrying from the brain to the body and vice versa. Together with the (PNS), which includes all nervous tissue outside of the central nervous system, the CNS controls virtually every activity in the body. The brain is protected by the skull, and the spinal cord is protected by the vertebrae . 
    ::中枢神经系统(CNS)包括大脑和脊髓(见图),代表着中枢神经系统的最大部分。大脑是神经系统的中央控制,而脊髓作为高速公路,从大脑携带到身体,反之亦然。与包括中枢神经系统外所有神经组织在内的中枢神经系统(PNS)一起,中枢神经系统几乎控制着身体的每一项活动。大脑受头骨保护,脊髓由脊椎保护。

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    The two main divisions of the human nervous system are the central nervous system and the peripheral nervous system. The peripheral nervous system has additional divisions. The components of the central nervous system are shown on the right.
    ::人类神经系统的两个主要部分是中枢神经系统和外围神经系统,外围神经系统有其他部分,中枢神经系统的部件在右侧显示。

    The Brain
    ::大脑

    The brain is the most complex organ in the body. The brain contains about 100 billion neurons—each of which can be connected to tens of thousands of other within the brain. The brain is the source of what makes us human: the conscious mind. The mind is the set of cognitive processes related to perception, interpretation, imagination, memories, and language. Beyond cognitive functions, the brain regulates processes related to such as respiration and heartbeat. An average adult human brain weighs between 1 and 1.5 kg (3 lb). An adult brain uses about 20-25% of the total energy used by the body, while the developing brain of an infant consumes around 60% of the total energy used by the body.
    ::大脑是身体中最复杂的器官。 大脑包含大约1000亿个神经元, 每一个神经元都可以与大脑中的其他数万个神经元连接。 大脑是使我们成为人类的源头: 有意识的大脑。 大脑是认知、 理解、 想象、 记忆和语言的一套认知过程。 除了认知功能之外, 大脑调节与呼吸和心跳有关的过程。 成人大脑的平均重量在1至1.5公斤之间( 3磅)。 成人大脑使用身体使用的总能量的大约20- 25%, 而婴儿的大脑消耗身体使用的总能量的60%左右。

    The parts of the brain can be classified by the processes they control. The cerebrum generally controls conscious functions such as problem-solving and speech, while the midbrain and the brain stem are more involved with unconscious (autonomic) functions such as breathing, heartbeat, and temperature regulation. The cerebellum is involved in coordination and control of body movement . 
    ::大脑的各个部分可以按它们控制的过程分类。大脑一般控制有意识的功能,如解决问题和言语,而中脑和脑干则更多地涉及无意识(航空)功能,如呼吸、心跳和温度调节。小脑参与身体运动的协调和控制。

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    In this drawing, assume you are looking at the left side of the head. This is how the brain would appear if you could look underneath the skull.
    ::在这幅画中,假设你正在看头部的左侧。这是大脑的表情,如果你可以看头骨下面。

    Cerebrum
    ::脑叶

    The cerebrum is what most people would think of as the "brain." The cerebrum lies on top of the brainstem. It is made up of two cerebral hemispheres, which are shown in  Figure . The two cerebral hemispheres are connected to each other at the corpus callosum, the dark-colored, X-shaped structure in the center of the image. The corpus callosum is a wide, flat bundle of axons found deep inside the brain. Mammals (including humans) have the largest and most well-developed cerebrums among all .
    ::脑部是大多数人认为的“脑”。脑部位于大脑的顶部。脑部由两个脑半球组成,图中显示。两个脑半球在图中互相连接,在图中显示。两个脑半球在图中相连接,在图中中心是黑色的、X形结构,在图中,两个脑部相连接。电图是大脑深处发现的一个宽宽、平板的斧子包。哺乳动物(包括人类)拥有最大和最发达的大脑。

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    A magnetic resonance image (MRI) of the human brain in which the two hemispheres of the cerebrum can be seen.
    ::人类大脑的磁共振图像(MRI) 可以看到大脑的两个半球。

    Each hemisphere of the cerebrum can be divided into four parts, or lobes. These lobes are named thusly: the frontal lobe, the parietal lobe, the temporal lobe, and the occipital lobe. Researchers have identified a number of functional areas within each lobe, some of which are listed in  Table . Both hemispheres look identical, but there are functional differences between them. For example, between right- and left-handed people, there are differences between the centers of function for spatial awareness. Each cerebral hemisphere both receives sensory information from and controls muscle movements of the opposite side of the body. Therefore, the right hemisphere controls the left side of the body, and the left hemisphere controls the right side of the body.
    ::大脑的每个半球可以分为四个部分, 或叶。 这些叶叶可以这样命名: 前叶、 面叶、 时间叶、 叶。 研究人员已经确定了每个叶中的若干功能领域, 有些在表格中列出 。 两个半球看起来都是一样的, 但是在功能上存在差异 。 例如, 右手和左手之间, 空间意识功能中心之间存在差异 。 每个脑半球都接收身体对面的感官信息并控制其肌肉运动 。 因此, 右半球控制身体的左侧, 左半球控制身体的右侧 。

    Functions Controlled by the Cerebral Lobes
    Lobe Functions
    Frontal Speech, intellectual function (reasoning, abstract thought, etc.), and touch
    Parietal Speech, taste , and reading
    Temporal Hearing and smell
    Occipital

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    The lobes of the cerebral cortex—frontal, temporal, occipital, and parietal. In vertebrates, a gross division into three major parts is used.
    ::在脊椎动物中,大脑皮层叶叶——前部、时部、顶部和顶部。在脊椎动物中,使用三大部分的毛分法。

    The cerebral cortex is the highly-folded outer layer of the cerebrum that is between 2 mm and 4 mm thick. The many folds in the cortex allow for the large surface area of the brain to fit inside the skull. The four lobes that make up the cerebral cortex, shown in  Figure , are named after the skull that cover those areas of the brain. The cerebral cortex controls higher functions such as consciousness, reasoning, emotions, and language. It also controls sensory functions such as touch, taste, smell, and responses to external stimuli . In the cerebrum, and found below the cerebral cortex, is the white matter. White matter is made up of myelinated axons that act as “cables” that link up certain parts of the right and left hemispheres.
    ::大脑皮层是大脑的高度外层,在2毫米至4毫米厚之间。 皮层的很多折叠使得大脑的大面积表面可以嵌入头骨中。 图中显示的构成大脑皮层的四个叶以大脑这些部分的头骨命名。 大脑皮层控制了较高功能, 如意识、 推理、 情感和语言等。 它还控制感官功能, 如触摸、 口味、 嗅觉和对外部皮质的反应。 在大脑皮层下发现的大脑皮层是白色物质。 白物质由作为“ 可连接”左右和左半球某些部分的宫颈组成。

    Diencephalon
    ::脑脑发

    The diencephalon is the region of the brain that includes structures such as the thalamus, the hypothalamus , and a portion of the pituitary gland . The thalamus is believed to “translate” sensory signals for the cerebral cortex, and it plays an important role in regulating states of sleep and wakefulness. The hypothalamus gland controls certain metabolic processes and other autonomic activities such as body temperature, hunger, thirst, and circadian cycles. The hypothalamus also makes and releases neurotransmitters that control the action of the pituitary gland. The thalamus, hypothalamus, and hippocampus together are considered part of a set of structures called the limbic system. The limbic system is considered the “emotional center” of the brain.
    ::脑脑部是大脑的区域,包括诸如Telamus、下丘脑和一部分垂体腺等结构。 据认为,脑膜膜是大脑皮层的“传输”感官信号,在调节睡眠和觉醒状态方面起着重要作用。 脑下脑膜控制着某些新陈代谢过程和其他自主活动,如身体温度、饥饿、口渴和环形循环。 脑下脑膜还产生并释放出控制脑洞腺动作的神经传导器。 脑膜、下丘体和河马坎普斯合在一起被视为一套称为肢体系统的结构的一部分。 肢体系统被视为大脑的“情感中心 ” 。

    Brain Stem
    ::脑干

    Sometimes called the “lower brain,” the brain stem is the lower part of the brain that is joined to the spinal cord. There are three parts to the brainstem: the midbrain, the pons, and the medulla oblongata, which are shown in  Figure . The brain stem is primarily involved in unconscious, autonomic functions as well as several types of sensory information. It also helps coordinate large body movements such as walking and running. The midbrain deals with sight and sound information and translates these inputs before sending them to the forebrain. The pons relays messages to other parts of the brain (primarily the cerebrum and cerebellum) and helps regulate breathing. Some researchers have hypothesized that the pons plays a role in dreaming. Some of the functions of the pons are shared by the medulla oblongata, also called the medulla. The medulla controls several subconscious homeostatic functions such as breathing, heart and activity, swallowing, and digestion .
    ::脑干有时被称为“ 低层大脑 ” , 脑干是大脑的下部部分, 与脊髓连接。 脑部有三个部分: 脑部、 pons 和 medull oblona, 图中显示了这些部分。 脑干主要与无意识、 自动功能以及多种感官信息有关。 它也有助于协调大型身体运动, 如行走和运行。 中脑处理视觉和声音信息, 并在将它们送入前脑前翻译这些输入。 将信息传递到大脑的其他部分( 主要是脑部和小脑) , 并帮助调节呼吸。 一些研究人员假设说, 在做梦中扮演的角色。 松子的一些功能由脑部的 obloata 共享, 也称为 medlongata 。 中脊控制了数个次意识的内部功能, 如呼吸、 心脏与活动、 吞咽与消化等 。

    One of the brain stem’s most important roles is that of an “information highway.” That is, all of the information coming from the body to the brain and the information from the cerebrum to the body go through the brain stem. Sensory pathways for such things as pain, temperature, touch, and pressure sensation go upward to the cerebrum, and motor pathways for movement and other body processes go downward to the spinal cord. Most of the axons in the motor pathways cross from one side of the CNS to the other as they pass through the medulla oblongata. As a result, the right side of the brain controls much of the movement in the left side of the body, and the left side of the brain controls much of the movement in the right side of the body.
    ::脑干最重要的作用之一是“信息高速公路 ” 。 也就是说,从身体到大脑的所有信息以及从大脑到身体的信息都通过脑干。 疼痛、温度、触摸和压力感觉等的感官途径向上传到大脑,运动和其他身体过程的动脉路径向下传到脊髓。 运动通道中的大多数斧子从CNS的一侧交叉到另一侧,当它们穿过脑膜蒙隆加时。 结果,大脑的右侧控制着身体左侧的大部分运动,而大脑左侧控制着身体右侧的许多运动。

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    The locations of the brainstem and cerebellum. The brainstem is in the center of this image. It is made up of the pons, medulla oblongata, and the midbrain. The cerebellum is the red structure to the right of the brainstem.
    ::脑电图和小脑电图的位置。 脑电图位于此图像的中心。 它由松子、 中脑和中脑组成。 脑电图是脑电图右侧的红结构 。

    Cerebellum
    ::

    The cerebellum is found just below the occipital lobe of the cerebrum. It plays an important role in coordination and the control of body movements. Many nerve pathways link the cerebellum with motor neurons . These neurons send information regarding when and where to move; they also transmit information on the position of the body in space. The cerebellum processes this information and uses the feedback on body position to fine-tune body movements. Hand-eye coordination is an example of such a function. Damage to the cerebellum does not cause paralysis, but the fine movements of the body, such as hand-eye coordination, balance , posture, and the ability to learn new motor skills, will be negatively affected. The cerebellum is the purple structure in Figure . A section of the cerebellum is shown in  Figure .
    ::脑膜下方的脑膜叶下方有脑膜,在协调和控制身体运动方面起着重要作用。许多神经路径将小脑与运动神经元连接起来。这些神经元发送有关运动时间和地点的信息;它们还传递关于身体在空间位置的信息。小脑处理这些信息,并利用身体位置的反馈微调身体运动。手心协调是这种功能的一个实例。小脑的损害不会造成瘫痪,但身体的细微移动,如手眼协调、平衡、姿态和学习新运动技能的能力,将受到负面影响。小脑是图中的紫形结构。小脑的一个部分在图中显示。

    Spinal Cord
    ::脊柱状

    The spinal cord, which is protected by the spinal vertebrae, is a thin, tubular bundle of nervous tissue that extends from the medulla oblongata and continues to the lower back, where it ends in a group of fibrous extensions. The main function of the spinal cord is as an information superhighway that links the sensory messages from the body to the brain. The outer cortex of the cord contains white matter (myelinated sensory and motor neurons). The central region, the gray matter, is made up of unmyelinated neurons. A cross section of the spinal cord is shown in Figure .
    ::脊椎脊椎脊椎保护的脊髓脊髓是一个薄的、管状的神经组织捆绑,它从脑膜上伸展到脑下部,一直到下部,以一组纤维扩展结束。脊髓的主要功能是将身体的感官信息与大脑连接起来的一条信息高速公路。脊髓的外皮皮层含有白色物质(感知和运动神经元)。中央区域是灰质,由未受记忆的神经元组成。脊髓的横截部分在图中显示。

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    Humanoid Robot Brains
    ::人体机器人脑

    The smartest people in the world have spent millions of dollars on developing high-tech robots. But even though technology has come a long way, these humanoid robots are nowhere close to having the "brain" and motor control of a human. Why is that? 
    ::世界上最聪明的人花费了数百万美元开发高科技机器人。 但尽管科技已经取得了长足进步,但这些人造机器人离拥有人类的“脑”和运动控制还差得远。 为什么呢?

     

     

    Summary
    ::摘要

    • The Central Nervous System consists of two parts: the brain and the spinal cord.
      ::中央神经系统由两部分组成:大脑和脊髓。
    • The spinal cord brings both sensory information from the body to the brain and instructions from the brain to the body.
      ::脊髓将感官信息从身体传到大脑 将指令从大脑传到身体
    • The brain stem is the lower part of the brain that directs subconscious homeostatic actions.
      ::脑干是大脑的下部部分 引导潜意识下自制动作
    • The cerebrum has four lobes: frontal, parietal, occipital, and temporal. It is in these four lobes that our conscious thoughts occur.
      ::脑部有四个叶子:前叶、前叶、顶叶、食堂和时间。正是在这四个叶子中,我们有意识地思考。

    Review
    ::回顾

    1. What is the Central Nervous System?
      ::什么是中央神经系统?
    2. Select five parts of the brain and explain what they do.
      ::选择大脑的五个部位, 并解释它们的工作 。

    Explore More
    ::探索更多