章节大纲

  • lesson content

    Case Study Conclusion: Fading Memory
    ::案例研究结论:消退记忆

    The illustration above shows some of the molecular and cellular changes that occur in Alzheimer’s disease (AD). Rosa was diagnosed with AD at the beginning of this chapter after experiencing memory problems and other changes in her cognitive functioning, mood, and personality. These abnormal changes in the brain include the development of amyloid plaques between brain cells and neurofibrillary tangles inside of neurons. These hallmark characteristics of AD are associated with the loss of synapses between neurons, and ultimately the death of neurons.
    ::以上插图显示了阿尔茨海默氏病(AD)中出现的一些分子和细胞变化。 罗莎在本章开始的时候被诊断为AD,当时她经历了记忆问题以及认知功能、情绪和个性方面的其他变化。 大脑中的这些异常变化包括脑细胞和神经元内神经纤维结壳之间的氨基甲状腺的发育。 AD的这些特征与神经元之间的突触和最终神经元的死亡有关。

    After reading this chapter, you should have a good appreciation for the importance of keeping neurons alive and communicating with each other at synapses. The nervous system coordinates all of the body’s voluntary and involuntary activities. It interprets information from the outside world through sensory systems, and makes appropriate responses through the motor system, through communication between the PNS and CNS. The brain directs the rest of the nervous system and controls everything from basic vital functions (such as heart rate and breathing) to high-level functions (such as problem solving and abstract thought). The nervous system can  perform these important functions by generating action potentials in neurons in response to stimulation and sending messages between cells at synapses, typically using chemical neurotransmitter molecules. When neurons are not functioning properly, lose their synapses, or die, they cannot carry out the signaling essential for the proper functioning of the nervous system.
    ::阅读本章之后, 您应该对保持神经元生命和在突触时相互沟通的重要性有很好的理解。 神经系统可以协调身体的所有自愿和非自愿活动。 它通过感官系统解释外部世界的信息,并通过运动系统做出适当的反应,通过PNS和CNS进行沟通。 大脑引导神经系统的其余部分,控制从基本关键功能(如心率和呼吸)到高层功能(如解决问题和抽象思维)的所有一切(如解决问题和抽象思维)的重要功能。 神经系统可以通过在神经元中产生行动潜力来发挥这些重要功能,对神经元的刺激作出反应,并在神经突触细胞之间发送信息,通常使用化学神经感应分子。 当神经元运转不正常,失去他们的突触或死亡时,他们无法执行神经系统正常运行所需的信号。

    AD is a progressive neurodegenerative disease, meaning that the damage to the brain becomes more extensive as time goes on. The picture illustrates how the damage progresses from before AD is diagnosed (preclinical AD), to mild and moderate AD, to severe AD.
    ::AD是一种累进性神经退化性疾病,这意味着对大脑的损害随着时间的流逝而变得更为广泛。 图片说明了在诊断AD之前的损害进展如何,从轻度和中度的AD到严重AD。

    lesson content

    Illustration showing the areas of the brain that become damaged as Alzheimer’s disease (AD) progresses. This is a side view along the middle of the brain, with the front of the brain shown to the left. Damaged areas are shown in blue.
    ::说明显示随着阿尔茨海默氏病(AD)的进化而受损的大脑区域。 这是大脑中间的侧面,左侧显示大脑前部。 受损区域以蓝色显示。

    You can see that the damage starts in a relatively small location toward the bottom of the brain. One of the earliest brain areas to be affected by AD is the hippocampus. As you have learned, the hippocampus is important for learning and memory, which explains why many of Rosa’s symptoms of mild AD involve deficits in memory, such as trouble remembering where she placed objects, recent conversations, and appointments.
    ::你可以看到,损害起源于大脑底部的相对小的地点。 受AD影响的最早的大脑区域之一是河马坎普斯。 正如你所了解的那样,河马坎普斯对于学习和记忆很重要,这解释了为什么罗莎的温和的AD症状中有许多与记忆不足有关,比如记不清她放置物体的地点、最近的对话和约会。

    As AD progresses, more of the brain is affected, including areas involved in emotional regulation, social behavior, planning, language, spatial navigation, and higher-level thought. Rosa is beginning to show signs of problems in these areas, including irritability, lashing out at family members, getting lost in her neighborhood, problems finding the right words, putting objects in unusual locations, and difficulty in managing her finances. You can see that as AD progresses, damage spreads further across the cerebrum, which you now know controls conscious functions like  reasoning, language, and interpretation of sensory stimuli. You can also see how the frontal lobe — which controls executive functions such as planning, self-control, and abstract thought — becomes increasingly damaged.
    ::随着AD的发展,更多的大脑受到影响,包括情感调节、社会行为、规划、语言、语言、空间导航和高层思想等领域。 罗莎开始显示出这些领域存在问题的迹象,包括刺激性、对家庭成员的鞭打、在邻里迷路、寻找正确语言的问题、将物体置于异常地点以及管理其财务的困难。你可以看到,随着AD的进步,损害会进一步蔓延到大脑中,而现在你已经知道它控制着理性、语言和感官刺激的解读等有意识的功能。你还可以看到控制规划、自我控制和抽象思维等行政功能的正面叶子是如何越来越受到破坏的。

    Increasing damage to the brain causes corresponding deficits in functioning. In moderate AD, patients have increased memory, language, and cognitive deficits, compared to mild AD. They may not recognize their own family members, and may wander and get lost, engage in inappropriate behaviors, become easily agitated, and have trouble carrying out daily activities such as dressing. In severe AD, much of the brain is affected. Patients usually cannot recognize family members or communicate, and they are often fully dependent on others for their care. They begin to lose the ability to control their basic functions, such as bladder control, bowel control, and proper swallowing. Eventually, AD causes death, usually as a result of this loss of basic functions.
    ::脑部日益受损导致相应的功能缺陷。 在中度残疾中,病人的记忆、语言和认知缺陷比温度残疾增加。 他们可能不承认自己的家庭成员,可能游荡和迷路,从事不适当的行为,容易引起骚动,并难以开展日常活动,如衣着。在严重残疾中,大部分大脑受到影响。病人通常无法认识家庭成员或沟通,而且往往完全依赖他人来照顾他们。他们开始丧失控制基本功能的能力,如膀胱控制、肠管和适当的吞咽。 最终,反倾销通常导致死亡,通常是由于基本功能的丧失。

    For now, Rosa only has mild AD and is still able to function relatively well with care from her family. The medication her doctor gave her has helped improve some of her symptoms. It is a cholinesterase inhibitor, which blocks an enzyme that normally degrades the neurotransmitter acetylcholine. With more of the neurotransmitter available, more of it can bind to neurotransmitter receptors on postsynaptic cells. Therefore, this drug acts as an agonist for acetylcholine, which enhances communication between neurons in Rosa’s brain. This increase in neuronal communication can help restore some of the functions lost in early Alzheimer’s disease and may slow the progression of symptoms.
    ::目前,罗莎只有温和的AD,并且仍然能够通过家人的照顾来保持相对良好的功能。 她的医生给她的药物帮助改善了她的某些症状。 它是一种胆碱酯酶抑制剂,它堵塞了通常会降解神经转移剂乙酰胆碱的酶。 随着更多的神经转移剂的出现,更多的神经转移剂可以与后合成细胞上的神经传递剂受体结合。 因此,这种药物可以作为乙酰胆碱的抗药剂,可以增强罗莎大脑神经元之间的沟通。 这种神经通信的增加可以帮助恢复早期老年痴呆症中丧失的一些功能,并可能减缓症状的蔓延。

    But medication such as this is only a short-term measure, and does not halt the progression of the underlying disease. Ideally, the damaged or dead neurons would be replaced by new, functioning neurons. Why does this not happen automatically in the body? As you have learned, neurogenesis is very limited in adult humans, so once neurons in the brain die, they are not normally replaced to any significant extent. S cientists, however, are studying the ways in which neurogenesis might be increased in cases of disease or injury to the brain. T hey are also investigating the possibility of using stem cell transplants to replace damaged or dead neurons with new neurons. But this research is in very early stages and is not currently a treatment for AD.
    ::但这种药物只是短期措施,不能阻止基本疾病的发展。 理想的情况是,受损或死亡的神经元将被新的、功能正常的神经元所取代。 为什么这不会在身体中自动发生? 正如你所知道的,神经的产生在成年人中非常有限,因此一旦大脑中的神经元死亡,通常不会被严重取代。然而,科学家们正在研究神经产生在疾病或脑损伤情况下可能增加的方法。他们也在研究用干细胞移植取代受损或死亡的神经元的可能性。但这项研究还处于很早期的阶段,目前不是AD的治疗。

    One promising area of research is in the development of methods to allow earlier detection and treatment of AD, given that the changes in the brain may actually start ten to 20 years before diagnosis of AD. A  radiolabeled chemical called Pittsburgh Compound B (PiB) binds to amyloid plaques in the brain, and in the future, it may be used in conjunction with brain imaging techniques to detect early signs of AD. Scientists are also looking for biomarkers in bodily fluids (such as blood and cerebrospinal fluid) that might indicate the presence of AD before symptoms appear. Finally, researchers are also investigating possible early and subtle symptoms (such as changes in how people move or a loss of smell) to see whether they can be used to identify people who will go on to develop AD. This research is in the early stages, but the hope is that patients can be identified earlier, allowing for earlier and more effective treatment, as well as more planning time for families. 
    ::一个大有希望的研究领域是制定方法,以便及早发现和治疗AD,因为大脑的变化实际上可能在诊断AD之前10至20年就开始了。 一种被称为匹兹堡化合物B(PiB)的放射性标签化学品与大脑中的氨基甲状腺结合,今后,它可能与大脑成像技术结合使用,以探测AD的早期迹象。 科学家们还在寻找体液(如血液和脑脊髓液)中的生物标志,这些标志可能表明AD在出现症状之前就已经存在。 最后,研究人员还在调查可能的早期和微妙症状(如人们移动方式的变化或气味的丧失),以了解是否可以利用这些症状来确定将开发AD的人。 这项研究尚处于早期阶段,但希望能够更早地发现病人,以便更早和更有效的治疗,以及家庭有更多规划时间。

    Scientists are also still trying to fully understand the causes of AD, which affects more than five million Americans. Some genetic mutations have been identified as contributors , but environmental factors also appear to be important. With more research into the causes and mechanisms of AD, hopefully a cure can be found, and people like Rosa can live a longer and better life.
    ::科学家们还在努力充分理解反倾销的原因 — — 它影响到500多万美国人。 某些基因突变被确定为贡献者,但环境因素似乎也很重要。 如果对反倾销的原因和机制进行更多的研究,希望能够找到解药,而像罗莎这样的人可以活得更长、更好的生活。

    Chapter Summary
    ::章次摘要

    In this chapter, you learned about the human nervous system. Specifically, you learned that:
    ::在本章中,你学会了人类神经系统。

    • The nervous system is the organ system that coordinates all of the body’s voluntary and involuntary actions by transmitting signals to and from different parts of the body. It has two major divisions: the central nervous system (CNS) and the peripheral nervous system (PNS).
      ::神经系统是协调身体所有自愿和非自愿行动的器官系统,通过向身体不同部分传送信号和从身体不同部分传送信号。 它有两大部分:中枢神经系统(CNS)和外围神经系统(PNS)。
      • The CNS includes the brain and spinal cord.
        ::CNS包括大脑和脊髓
      • The PNS consists mainly of nerves that connect the CNS with the rest of the body. It has two major divisions: the somatic nervous system and the autonomic nervous system. These divisions control different types of functions, and often interact with the CNS to carry out these functions.  The somatic system controls activities that are under voluntary control. The autonomic system controls activities that are involuntary.
        ::PNS主要由将CNS与身体其他部分连接在一起的神经组成,它有两大部分:体质神经系统和自主神经系统。这些部分控制着不同类型的功能,并经常与CNS互动以履行这些功能。体质系统控制着自愿控制的活动。自动系统控制着非自愿的活动。
        • The autonomic nervous system is further divided into the sympathetic division (which controls the fight-or-flight response), the parasympathetic division (which controls most routine involuntary responses), and the enteric division (which provides local control for digestive processes).
          ::自主神经系统进一步划分为同情分化(控制战斗或飞行反应)、寄生虫病分化(控制大多数例行非自愿反应)和肠道分化(对消化过程进行局部控制)。

        ::自主神经系统进一步划分为同情分化(控制战斗或飞行反应)、寄生虫病分化(控制大多数例行非自愿反应)和肠道分化(对消化过程进行局部控制)。

      ::PNS主要由神经组成,将CNS与身体的其余部分连接在一起。它有两大部分:体质神经系统和自动神经系统。这些部分控制着不同类型的功能,并经常与CNS互动以履行这些功能。体力系统控制着自愿控制下的活动。自动神经系统控制着非自愿的活动。自动神经系统进一步分为同情分工(控制战斗或飞行反应)、寄生虫分(控制大多数例行非自愿反应)和肠道分(对消化过程进行局部控制)。
    • Signals sent by the nervous system are electrical signals called nerve impulses. They are transmitted by special, electrically excitable cells called neurons, which are one of two major types of cells in the nervous system.
      ::神经系统发出的信号是被称为神经脉冲的电讯号,通过神经系统两大类细胞之一,即神经系统神经元,通过特别的、电动可刺激的细胞神经元传送。
    • Glial cells are the other major type of nervous system cells. There are many types of glial cells, and they have many specific functions. In general, glial cells function to support, protect, and nourish neurons.
      ::粘结细胞是神经系统细胞的另一种主要类型。 有很多类型的滑翔细胞,它们有许多特定的功能。 一般来说,滑翔细胞功能支持、保护和营养神经元。
    • The main parts of a neuron include the cell body, dendrites, and axon. The cell body contains the nucleus. Dendrites receive nerve impulses from other cells, and the axon transmits nerve impulses to other cells at axon terminals. A synapse is a complex membrane junction at the end of an axon terminal that transmits signals to another cell.
      ::神经元的主要部分包括细胞体、 dendrites 和 axon 。 细胞体包含核。 Dendrites 接收其他细胞的神经脉冲, 轴将神经脉冲传输到轴终端的其他细胞。 突触是一个复杂的膜交叉点, 位于轴终端的尾端, 将信号传输到另一个细胞 。
    • Axons are often wrapped in an electrically-insulating myelin sheath, which is produced by glial cells. Electrical impulses called action potentials occur at gaps in the myelin sheath, called nodes of Ranvier, which speeds the conduction of nerve impulses down the axon. 
      ::轴心往往被包裹在由滑翔细胞产生的电绝缘弥丁叶草丛中。 被称为行动潜力的电动脉冲发生在被称作Ranvier节点的弥叶林草丛的缝隙中,它加速了轴心下神经脉冲的传导。
    • Neurogenesis, or the formation of new neurons by cell division, may occur in a mature human brain — but only to a limited extent.
      ::神经起源,或细胞分裂形成新的神经元,可能发生在成熟的人类大脑中,但程度有限。
    • The nervous tissue in the brain and spinal cord consists of gray matter — which contains mainly unmyelinated cell bodies and dendrites of neurons — and white matter, which contains mainly myelinated axons of neurons. Nerves of the peripheral nervous system consist of long bundles of myelinated axons that extend throughout the body.
      ::大脑和脊髓的神经组织由灰质和白质组成,灰质主要包括无线细胞体和神经元的外形;白质主要包括神经元的近线轴;外围神经系统的神经神经系统由长串的近线轴组成,贯穿整个身体。
    • There are hundreds of types of neurons in the human nervous system, but many can be classified on the basis of the direction in which they carry nerve impulses. Sensory neurons carry nerve impulses away from the body and toward the central nervous system, motor neurons carry them away from the central nervous system and toward the body, and interneurons often carry them between sensory and motor neurons.
      ::人类神经系统有数百种神经元,但许多神经元可以按照携带神经脉冲的方向进行分类。 感官神经元携带神经脉冲离开身体,进入中枢神经系统,动脉神经元携带神经脉冲离开中枢神经系统,动脉神经元将神经神经元从中枢神经系统和身体转移到中枢神经系统,而中中枢经常携带神经神经元和运动神经元。
    • A nerve impulse is an electrical phenomenon that occurs because of a difference in electrical charge across the plasma membrane of a neuron.
      ::神经冲动是一种电子现象,由于神经元等离子膜的电荷差异而出现。
    • The sodium-potassium pump maintains an electrical gradient across the plasma membrane of a neuron when it is not actively transmitting a nerve impulse. This gradient is called the resting potential of the neuron.
      ::钠-钾泵在神经元的等离子膜上保持电子梯度,当它不积极传播神经脉冲时。这个梯度被称为神经元的休息潜力。
    • An action potential is a sudden reversal of the electrical gradient across the plasma membrane of a resting neuron. It begins when the neuron receives a chemical signal from another cell or some other type of stimulus. The action potential travels rapidly down the neuron’s axon as an electric current.
      ::行动潜力是休息神经元等离子膜的电梯度突如其来的逆转。 当神经元从另一个细胞或某种其他类型的刺激中收到化学信号时,行动潜力就开始了。 行动潜力会以电流的形式迅速从神经元的斧子上流下来。
    • A nerve impulse is transmitted to another cell at either an electrical or a chemical synapse. At a chemical synapse, neurotransmitter chemicals are released from the presynaptic cell into the synaptic cleft between cells. The chemicals travel across the cleft to the postsynaptic cell and bind to receptors embedded in its membrane.
      ::神经脉冲在电气或化学突触时被传送到另一个细胞,在化学突触时,神经传感化学物质从预先合成细胞释放到细胞之间的合成裂缝中,化学品穿过裂缝进入后合成细胞,并与嵌入其膜内的受体捆绑在一起。
    • There are many different types of neurotransmitters. Their effects on the postsynaptic cell generally depend on the type of receptor they bind to. The effects may be excitatory, inhibitory, or modulatory in more complex ways. Both physical and mental disorders may occur if there are problems with neurotransmitters or their receptors.
      ::神经传导器种类多种多样,对后合成细胞的影响一般取决于它们所捆绑的受体类型,其影响可能是刺激性、抑制性或调节性更复杂,如果神经传导器或其受体有问题,则可能出现身体和精神紊乱。
    • The CNS includes the brain and spinal cord. It is physically protected by bones, meninges, and cerebrospinal fluid. It is chemically protected by the blood-brain barrier.
      ::CNS包括大脑和脊髓,由骨头、脑膜和脑脊髓液进行物理保护,由血脑屏障进行化学保护。
    • The brain is the control center of the nervous system and of the entire organism. The brain uses a relatively large proportion of the body’s energy, primarily in the form of glucose.
      ::大脑是神经系统和整个生物体的控制中心。 大脑使用身体能量的相对较大比例,主要是葡萄糖。
      • The brain is divided into three major parts, each with different functions: brain stem, cerebellum, and cerebrum. The cerebrum is further divided into left and right hemispheres. Each hemisphere has four lobes: frontal, parietal, temporal, and occipital. Each lobe is associated with specific senses or other functions.
        ::大脑分为三个主要部分,每个部分的功能不同:脑干、小脑和大脑。大脑进一步分为左半球和右半球。每个半球有四个叶子:前叶、双叶、时间叶和食堂。每个叶子都与特定感官或其他功能有关。
      • The cerebrum has a thin outer layer called the cerebral cortex. Its many folds give it a large surface area. This is where most information processing takes place.
        ::大脑外层薄薄,叫做脑皮层。它的很多折叠给它提供了大面积的表面积。这是大部分信息处理的地方。
      • Inner structures of the brain include the hypothalamus (which controls the endocrine system via the pituitary gland) and the thalamus (which has several involuntary functions).
        ::大脑的内部结构包括下脑膜(通过垂体腺控制内分泌系统)和大脑(具有若干非自愿功能)。

      ::大脑分为三个主要部分, 每个部分有不同的功能: 大脑干、 脑脑和脑。 大脑进一步分为左半球和右半球。 每个半球有四个叶子: 前部、 等子体、 时空 和 食堂。 每个叶子都与特定的感官或其他功能相关。 大脑有一个薄的外层, 叫做大脑皮层。 它的许多折叠给它一个大面积的表面积。 这是大部分信息处理工作的地方。 大脑的内部结构包括下脑( 它通过水下腺控制内分泌系统) 和地中海( 它有一些非自愿的功能 ) 。
    • The spinal cord is a tubular bundle of nervous tissues that extends from the head down the middle of the back to the pelvis. It functions mainly to connect the brain with the PNS. It also controls certain rapid responses called reflexes without input from the brain.
      ::脊髓是由神经组织组成的管状捆绑,从头部向下从背部中间延伸至骨盆,主要功能是连接大脑和PNS。它还控制着一些叫作反射的快速反应,而没有大脑输入。
      • A spinal cord injury may lead to paralysis (loss of sensation and movement) of the body below the level of the injury, because nerve impulses can no longer travel up and down the spinal cord beyond that point.
        ::脊髓损伤可能导致身体瘫痪(失去感觉和运动),低于受伤水平,因为神经脉冲不能再在脊髓上下移动超过该点。

      ::脊髓损伤可能导致身体瘫痪(失去感觉和运动),低于受伤水平,因为神经脉冲不能再在脊髓上下移动超过该点。
    • The PNS consists of all the nervous tissue that lies outside of the CNS. Its main function is to connect the CNS to the rest of the organism.
      ::PNS由CNS以外的所有神经组织组成,其主要功能是将CNS与生物体的其他部分连接起来。
      • The tissues that make up the PNS are nerves and ganglia. Nerves are bundles of axons and ganglia are groups of cell bodies.  Nerves are classified as sensory, motor, or a mix of the two.
        ::构成PNS的组织是神经和帮派的。神经是斧子的捆绑,而帮派是细胞身体的组合。神经被归类为感官、马达或两者的混合。
      • The PNS is not as well protected physically or chemically as the CNS, so it is more prone to injury and disease. PNS problems include injury from diabetes, shingles, and heavy metal poisoning. Two disorders of the PNS are Guillain-Barre syndrome and Charcot-Marie-Tooth disease.
        ::PNS在身体或化学上没有像CNS那样受到良好的保护,因此更容易受伤和患病。 PNS的问题包括糖尿病、发青和重金属中毒造成的伤害。 PNS的两种疾病是Gelain-Barre综合症和Charcot-Marie-Tooth病。

      ::构成PNS的组织是神经和帮派的。Nerves是一群斧子和帮派的细胞体。Nerves被归类为感官、马达或两者的混合体。PNS没有像CNS那样受到身体或化学的保护,因此更容易受伤和患病。PNS的问题包括糖尿病、发烧和重金属中毒造成的伤害。PNS的两种疾病是Guillain-Barre综合症和Charcot-Marie-Tooth病。
    • The human body has two major types of senses: special senses and general senses. Special senses have specialized sense organs and include vision (eyes), hearing (ears), balance (ears), taste (tongue), and smell (nasal passages). General senses are all associated with touch and lack special sense organs. Touch receptors are found throughout the body but particularly in the skin.
      ::人体有两种主要的感官类型:特殊感官和一般感官。特殊感官有专门的感官器官,包括视力(眼睛)、听力(耳)、平衡(耳)、口感(舌头)和嗅觉(鼻孔 ) 。一般感官都与触摸有关,缺乏特殊感官器官。触摸感应器存在于全身,特别是在皮肤中。
    • All senses depend on sensory receptor cells to detect sensory stimuli and transform them into nerve impulses. Types of sensory receptors include mechanoreceptors (mechanical forces), thermoreceptors (temperature), nociceptors (pain), photoreceptors (light), and chemoreceptors (chemicals).
      ::所有感官都依赖感官受体细胞来检测感官刺激,并将其转化为神经脉冲。 感官受体的类型包括机械感官(机械力 ) 、 热受体( 温度 ) 、 鼻受体( 帕因 ) 、 光受体( 灯光 ) 和 电机受体( 化学 ) 。
      • Touch includes the ability to sense pressure, vibration, temperature, pain, and other tactile stimuli. The skin includes several different types of touch receptor cells.
        ::触摸包括感应压力、振动、温度、疼痛和其他触觉刺激。皮肤包括几种不同类型的触摸受体细胞。
      • Vision is the ability to sense light and see. The eye is the special sensory organ that collects and focuses light, forms images, and changes them to nerve impulses. Optic nerves send information from the eyes to the brain, which processes the visual information and “tells” us what we are seeing.
        ::视觉是感知光和视觉的能力。 眼睛是特殊的感官器官,收集和聚焦光,形成图像,将其改变为神经冲动。 光神经将信息从眼睛传递到大脑,它处理视觉信息和我们所看到的“言语 ” 。
        • Common vision problems include myopia (nearsightedness), hyperopia (farsightedness), and presbyopia (age-related decline in close vision).
          ::常见的视力问题包括近视(近视)、高视(远视)和远视(近视与年龄有关的下降)。

        ::常见的视力问题包括近视(近视)、高视(远视)和远视(近视与年龄有关的下降)。
      • Hearing is the ability to sense sound waves, and the ear is the organ that senses sound. It changes sound waves to vibrations that trigger nerve impulses, which travel to the brain through the auditory nerve. The brain processes the information and “tells” us what we are hearing.
        ::听力是感知声波的能力,耳是感知声音的器官。 它将声波改变为触发神经脉冲的震动,神经脉冲通过听力神经进入大脑。 大脑处理我们听到的信息和“声音 ” 。
      • The ear is also the organ responsible for the sense of balance, which is the ability to sense and maintain an appropriate body position. The ears send impulses on head position to the brain, which sends messages to skeletal muscle via the peripheral nervous system. The muscles respond by contracting to maintain balance.
        ::耳朵也是负责平衡感的器官,即感知和保持适当身体姿势的能力; 耳朵向大脑发出头部姿势的脉冲,脑部通过边缘神经系统向骨骼肌肉发出信息; 肌肉通过接触保持平衡作出反应。
      • Taste and smell are both abilities to sense chemicals. Taste receptors in taste buds on the tongue sense chemicals in food, and olfactory receptors in the nasal passages sense chemicals in the air. The sense of smell contributes significantly to the sense of taste.
        ::口味和嗅觉都是感知化学物质的能力。 口语感化学物质在食物中的味蕾和鼻孔中的嗅觉受体在空气中感知化学物质。 嗅觉感能极大地促进品味感。

      ::触摸触摸包括感应、 振动、 温度、 疼痛和其他触觉刺激的能力。 皮肤包括几种不同的触摸受体细胞。 视觉是感知光和视觉的能力。 视觉是感知光和视觉的能力。 眼睛是收集和聚焦光、 形状图像和将其改变为神经冲动的特殊感官器官。 光神经从眼睛向大脑传递信息, 处理视觉信息和我们所看到的“ 触觉” 。 常见的视觉问题包括近视( 视力)、 超视( 视力) 和前视( 与年龄有关的下降近视) 。 听觉是感知声波的能力, 耳朵是感知声音的器官。 它会改变震动波, 触发神经冲动, 通过听觉神经传到大脑。 大脑处理信息, “ 感知” 我们所听到的东西。 耳朵也是对平衡感负责的器官, 也就是感知和保持适当的身体位置的能力。 耳朵将头部的脉冲传递到脑部位置, 将感知波状传到大脑, 感官的感官感官和感官的感官的感官能力将感官的感官的体。 感官的感官将感官的感官的感官的感官的感官的感官的感官和感官能力将感官的感官的感官能力传到感官的体。 感官的感官的感官的感官的感。 。 。 。 。 。 感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感官的感力的感力的感。 。 。 。 。 。 的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的感力的
    • Psychoactive drugs are substances that change the function of the brain and result in alterations of mood, thinking, perception, and behavior. They include prescription medications (such as opioid painkillers), legal substances (such as nicotine and alcohol), and illegal drugs (such as LSD and heroin).
      ::精神活性药物是改变大脑功能并导致情绪、思想、感知和行为的改变的物质,包括处方药(如类阿片止痛剂)、合法物质(如尼古丁和酒精)和非法药物(如迷幻药和海洛因)。
    • Psychoactive drugs are divided into different classes according to their pharmacological effects. They include stimulants, depressants, anxiolytics, euphoriants, hallucinogens, and empathogens. Many psychoactive drugs have multiple effects, so they may be placed in more than one class.
      ::精神活性药物根据其药理效应分为不同的类别,包括兴奋剂、镇静剂、厌解剂、兴奋剂、致幻剂、致幻剂和病原体。 许多精神活性药物具有多重影响,因此可以归入一个以上类别。
    • Psychoactive drugs generally produce their effects by affecting brain chemistry. Generally, they act either as agonists — which enhance the activity of particular neurotransmitters — or as antagonists, which decrease the activity of particular neurotransmitters.
      ::精神活性药物通常通过影响脑化学而产生效果,一般而言,它们要么是作为刺激剂(这加强了某些神经传导剂的活动),要么是作为对抗剂,减少某些神经传导剂的活动。
    • Psychoactive drugs are used for medical, ritual, and recreational  purposes.
      ::精神活性药物用于医疗、仪式和娱乐目的。
    • Misuse of psychoactive drugs may lead to addiction, which is the compulsive use of a drug, despite its negative consequences. Sustained use of an addictive drug may produce physical or psychological dependence on the drug. Rehabilitation typically involves psychotherapy, and sometimes the temporary use of other psychoactive drugs.
      ::滥用精神活性药物可能导致吸毒成瘾,即强制使用一种药物,尽管其消极后果是负面的。 持续使用上瘾药物可能导致对药物的身体或心理依赖。 康复通常包括心理治疗,有时是临时使用其他精神活性药物。

    In addition to the nervous system, there is another system of the body that is important for coordinating and regulating many different functions – the endocrine system. You will learn about the endocrine system in the next chapter.
    ::除了神经系统之外,还有另一个身体系统,对于协调和调节许多不同功能 — — 内分泌系统 — — 非常重要。 您将在下一章了解内分泌系统。

    Chapter Summary Review 
    ::" 概述 " 章次

    1. Imagine that you decide to make a movement. To carry out this decision, a neuron in the cerebral cortex of your brain (neuron A) fires a nerve impulse that is sent to a neuron in your spinal cord (neuron B). Neuron B then sends the signal to a muscle cell, causing it to contract, resulting in movement. Answer the following questions about this pathway.
    ::1. 想象一下,你决定进行运动。为了执行这一决定,大脑大脑皮层(A中子)中的神经元(A中子)释放神经冲动,送往脊髓(B中子)中的神经脉冲。然后,B中子将信号发送到肌肉细胞,导致细胞收缩,导致运动。回答以下关于这条路径的问题。

    a. Which part of the brain is neuron A located in — the cerebellum, cerebrum, or brain stem? Explain how you know.
    ::a. 大脑的哪个部分是神经元A,位于小脑、脑或脑干?解释你怎么知道。

    b. The cell body of neuron A is located in a lobe of the brain that is involved in abstract thought, problem solving, and planning. Which lobe is this?
    ::b. 神经元A的细胞体位于大脑的叶子上,它涉及抽象的思考、解决问题和规划。这是哪个叶子?

    c. Part of neuron A travels all the way down to the spinal cord to meet neuron B. Which part of neuron A travels to the spinal cord?
    ::c. 神经元A的一部分一直到脊髓,以满足神经元B。 神经元A的哪一部分到脊髓?

    d. Neuron A forms a chemical synapse with neuron B in the spinal cord. How is the signal from neuron A transmitted to neuron B?
    ::d. 中子A形成脊髓神经元B的化学突触,神经元A的信号如何传送到神经元B?

    e. Is neuron A in the central nervous system (CNS) or peripheral nervous system (PNS)?
    ::e. 神经元A是否在中枢神经系统(CNS)或外围神经系统(PNS)中?

    f. The axon of neuron B travels in a nerve to a skeletal muscle cell. Is the nerve part of the CNS or PNS? Is this an afferent nerve or an efferent nerve?
    ::f. 神经元B的轴向直通骨骼肌肉细胞,是CNS或PNS的神经部分吗?这是迟缓的神经还是缓缓的神经?

    g. What part of the PNS is involved in this pathway — the autonomic nervous system or the somatic nervous system? Explain your answer.
    ::g. PNS的哪些部分涉及这一途径——自体神经系统还是体质神经系统?解释你的答复。

    2. What are the differences between a neurotransmitter receptor and a sensory receptor?
    ::2. 神经传感器受体与感官受体之间有什么区别?

    3. Which part of a postsynaptic neuron typically receives the signals from a presynaptic neuron?
    ::3. 后合成神经元的哪个部分通常接收预合成神经元的信号?

    a. the axon terminal
    ::a. 轴轴终端

    b. the nodes of Ranvier
    ::b. 兰维尔节点

    c. the dendrites
    ::c. 标记

    d. the cell body
    ::d. 细胞体

    4. True or False:  Glial cells produce action potentials.
    ::4. 真实或虚假:粘贴细胞产生行动潜力。

    5. True or False:  The spinal cord consists of white matter only.
    ::5. 真实或假:脊髓仅由白物质组成。

    6. True or False:  Axons may be more than a meter long in adult humans.
    ::6. 真实或假:在成年人中,轴数可能超过1米长。

    7. If a person has a stroke and then  has trouble using language correctly, which hemisphere of their brain was most likely damaged? Explain your answer.
    ::7. 如果一个人中风,然后对正确使用语言有困难,他们的大脑哪个半球最有可能受损?解释你的答复。

    8. The right side of the brain generally controls the ____________ of the body.
    ::8. 大脑右侧一般控制身体的...。

    a. right side
    ::a. 右侧

    b. left side
    ::b. 左侧

    c. head region
    ::c. 总部地区

    d. trunk and leg regions
    ::d. 大干区和大腿区

    9. Electrical gradients are responsible for the resting potential and action potential in neurons. Answer the following questions about the electrical characteristics of neurons.
    ::9. 电梯度是神经元休息潜力和行动潜力的原因,回答以下关于神经元电子特性的问题。

    a. Define an electrical gradient, in the context of a cell.
    ::a. 在单元格上下文中界定电梯度。

    b. What is responsible for maintaining the electrical gradient that results in the resting potential?
    ::b. 维持产生休息潜力的电梯度的责任是什么?

    c. Compare and contrast the resting potential and the action potential.
    ::c. 比较和比较休息潜力和行动潜力。

    d. Where along a myelinated axon does the action potential occur? Why does it happen here?
    ::d. 可能发生作用的粒子轴沿何方?为什么发生在这里?

    10. What does it mean that the action potential is “all-or-none?”
    ::10. 行动潜力是 " 万无一? " 是什么意思?

    11. What determines whether a neurotransmitter has an excitatory or inhibitory effect? Choose the best answer.
    ::11. 由什么决定神经传播器是否具有刺激作用或抑制作用?选择最好的答案。

    a. the neurotransmitter itself
    ::a. 神经传输器本身

    b. the specific receptor for the neurotransmitter on the postsynaptic cell
    ::b. 后合成细胞神经传输器的具体受体

    c. the number of synaptic vesicles in the axon terminal
    ::c. xxon 终端中的合成囊囊的数目。

    d. whether it is in a sensory neuron or a motor neuron
    ::d. 是感官神经元还是运动神经元。

    12. Compare and contrast Schwann cells and oligodendrocytes.
    ::12. 比较和对比Schwann细胞和寡头催化细胞。

    13. True or False:  The cerebellum makes up most of the brain and is divided into four lobes.
    ::13. 真实或假:小脑构成大脑的大部分,分为四个叶子。

    14. True or False:  The hypothalamus is part of the brain.
    ::14. 真实或假:下脑膜是大脑的一部分。

    15. Which lobe of the brain processes touch information?
    ::15. 大脑的哪个叶子处理触摸信息?

    a. parietal
    ::a. 等同

    b. occipital
    ::b. 食疗

    c. mechanical
    ::c. 机械

    d. temporal
    ::d. 时间

    16. Information about sounds is mainly sent to which lobe of the brain?
    ::16. 有关声音的信息主要发送到大脑的哪个叶子?

    a. parietal
    ::a. 等同

    b. occipital
    ::b. 食疗

    c. cochleal
    ::c. 焦耳

    d. temporal
    ::d. 时间

    17. Rods and cones in the retina are _________________.
    ::17. 视网膜中的网球和锥形是__________________________________________________________________________________________________________________________________

    a. mechanoreceptors
    ::a. 机械受体

    b. nociceptors
    ::b. 接收器

    c. photoreceptors
    ::c. 光受体

    d. chemoreceptors
    ::d. 切乳受体

    18. For the senses of smell and hearing, name their respective sensory receptor cells, what type of receptor cells they are, and what stimuli they detect.
    ::18. 对于嗅觉和听觉感官,应说明各自的感官受体细胞、它们是什么类型的受体细胞,以及它们检测到什么刺激因素。

    19. True or False:  Sensory information such as smell, taste, and sound, are carried to the CNS by cranial nerves.
    ::19. 真实或假的:气味、品味和声音等感官信息由冠状神经携带到CNS。

    20. True or False:  The parasympathetic nervous system is a division of the central nervous system.
    ::20. 真实或假:寄生虫同情性神经系统是中枢神经系统的分割。

    21. Nicotine is a psychoactive drug that binds to and activates a receptor for the neurotransmitter acetylcholine. Is nicotine an agonist or an antagonist for acetylcholine? Explain your answer.
    ::21. 尼古丁是一种精神活性药物,它与神经分质乙酰胆碱结合并激活一种受体,尼古丁是乙酰胆碱的激动剂还是对乙酰胆碱的对抗剂?解释你的答案。