Neuroscience For Dummies E-Book

Frank Amthor

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch
• Veröffentlichungsjahr: 2016

Seitenzahl: 611

Beschreibung

Get on the fast track to understanding neuroscience Investigating how your senses work, how you move, and how you think and feel, Neuroscience For Dummies, 2nd Edition is your straight-forward guide to the most complicated structure known in the universe: the brain. Covering the most recent scientific discoveries and complemented with helpful diagrams and engaging anecdotes that help bring the information to life, this updated edition offers a compelling and plain-English look at how the brain and nervous system function. Simply put, the human brain is an endlessly fascinating subject: it holds the secrets to your personality, use of language, memories, and the way your body operates. In just the past few years alone, exciting new technologies and an explosion of knowledge have transformed the field of neuroscience--and this friendly guide is here to serve as your roadmap to the latest findings and research. Packed with new content on genetics and epigenetics and increased coverage of hippocampus and depression, this new edition of Neuroscience For Dummies is an eye-opening and fascinating read for readers of all walks of life. * Covers how gender affects brain function * Illustrates why some people are more sensitive to pain than others * Explains what constitutes intelligence and its different levels * Offers guidance on improving your learning What is the biological basis of consciousness? How are mental illnesses related to changes in brain function? Find the answers to these and countless other questions in Neuroscience For Dummies, 2nd Edition

Leseprobe

Neuroscience For Dummies®, 2nd Edition

Published by: John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030-5774, www.wiley.com

Copyright © 2016 by John Wiley & Sons, Inc., Hoboken, New Jersey

Published simultaneously in Canada

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Library of Congress Control Number: 2016933973

ISBN 978-1-119-22489-1 (pbk); ISBN 978-1-119-22491-4 (ebk); ISBN 978-1-119-22490-7 (ebk)

Neuroscience For Dummies®

To view this book's Cheat Sheet, simply go to www.dummies.com and search for “Neuroscience For Dummies Cheat Sheet” in the Search box.

Table of Contents

Cover

Introduction

About This Book

Foolish Assumptions

Icons Used in This Book

Beyond This Book

Where to Go from Here

Part 1: Introducing the Nervous System

Chapter 1: A Quick Trip through the Nervous System

Understanding the Evolution of the Nervous System

Looking at How the Nervous System Works

Looking at the Basic Functions of the Nervous System

When Things Go Wrong: Neurological and Mental Illness

Revolutionizing the Future: Advancements in Various Fields

Chapter 2: All about the Brain and Spinal Cord

Looking Inside the Skull: The Brain and Its Parts

The Spinal Cord: The Intermediary between Nervous Systems

Fighting or Fleeing: The Autonomic Nervous System

How We Know What We Know about Neural Activity

Chapter 3: Understanding How Neurons Work

Neuron Basics: Not Just Another Cell in the Body

How Shocking! Neurons as Electrical Signaling Devices

Moving Around with Motor Neurons

Non-neuronal Cells: Glial Cells

Recording Techniques

Part 2: Translating the Internal and External World through Your Senses

Chapter 4: Feeling Your Way: The Skin Senses

How Do You Feel? The Lowdown on the Skin and Its Sensory Neurons

Skin Receptors, Local Spinal Circuits, and Projections to the Brain

Understanding the Complex Aspects of Pain

Chapter 5: Looking at Vision

The Eyes Have It: A Quick Glance at Your Eyes

From the Eyes to the Vision Centers of the Brain

Impaired Vision and Visual Illusions

Chapter 6: Sounding Off: The Auditory System

The Ear: Capturing and Decoding Sound Waves

Making Sense of Sounds: Central Auditory Projections

Locating Sound

I Can’t Hear You: Deafness and Tinnitus

Chapter 7: Odors and Taste

What’s That Smell?

Having Good Taste

The Role of Learning and Memory in Taste and Smell

Lacking Taste and Smelling Badly

Part 3: Moving Right Along: Motor Systems

Chapter 8: Movement Basics

Identifying Types of Movement

Controlling Movement: Central Planning and Hierarchical Execution

Pulling the Load: Muscle Cells and Their Action Potentials

Muscle and Muscle Motor Neuron Disorders

Chapter 9: Coordinating Things More: The Spinal Cord and Pathways

The Withdrawal Reflex: An Open-Loop Response

Hold Your Position! Closed-Loop Reflexes

The Modulating Reflexes: Balance and Locomotion

Correcting Errors without Feedback: The Cerebellum

Chapter 10: Planning and Executing Actions

Making the Move from Reflexes to Conscious or Goal-Generated Action

Where Are the Free Will Neurons?

Discovering New (and Strange) Neurons

When the Wheels Come Off: Motor Disorders

Chapter 11: Unconscious Actions with Big Implications

Working behind the Scenes: The Autonomic Nervous System

Sweet Dreams: Sleep and Circadian Rhythms

Part 4: Intelligence: The Thinking Brain and Consciousness

Chapter 12: Understanding Intelligence, Consciousness, and Emotions

Defining Intelligence

Intelligence about Emotions

Understanding Consciousness

Chapter 13: How the Brain Processes Thoughts

The Brain: Taking Command at Multiple Levels

All about the Neocortex

Controlling the Content of Thought: Sensory Pathways and Hierarchies

Dividing and Conquering: Language, Vision, and the Brain Hemispheres

Where Consciousness Resides

Chapter 14: The Executive Brain

Getting the Brain You Have Today: The Neocortex versus Your Reptilian Brain

Working Memory, Problem-Solving, and the Lateral Prefrontal Cortex

Making Up and Changing Your Mind: The Orbitofrontal Cortex

Are We There Yet? The Anterior Cingulate Cortex

Chapter 15: Learning and Memory

Learning and Memory: One More Way to Adapt to the Environment

Sending More or Fewer Signals: Adaptation versus Facilitation

Exploring What Happens during Learning: Changing Synapses

The Role of the Hippocampus in Learning and Memory

Losing Your Memory: Forgetting, Amnesia, and Other Disorders

Getting Brainier: Improving your Learning

Chapter 16: Developing and Modifying Brain Circuits: Plasticity

Developing from Conception

Learning from Experience: Plasticity and the Development of Cortical Maps

Taking the Wrong Path: Nervous System Disorders of Development

The Aging Brain

Chapter 17: Neural Dysfunctions, Mental Illness, and Drugs That Affect the Brain

Looking at the Causes and Types of Mental Illness

The Promise of Pharmaceuticals

Part 5: The Part of Tens

Chapter 18: Ten (Or So) Crucial Brain Structures

The Neocortex

The Thalamus, Gateway to the Neocortex

The Pulvinar

The Cerebellum

The Hippocampus

Wernicke’s and Broca’s Areas

The Fusiform Face Area

The Amygdala

The Lateral Prefrontal Cortex

The Substantia Nigra (Basal Ganglia)

The Anterior Cingulate Cortex

Chapter 19: Ten Tricks of Neurons That Make Them Do What They Do

Overcoming Neurons’ Size Limit

Getting the Biggest Bang for the Buck with Dendritic Spines

Ligand-Gated Receptors: Enabling Neurons to Communicate Chemically

Getting Specialized for the Senses

Computing with Ion Channel Currents

Keeping the Signal Strong across Long Distances

The Axon: Sending Signals from Head to Toe

Speeding Things Up with Myelination

Neural Homeostasis

Changing Synaptic Weights to Adapt and Learn

Chapter 20: Ten Amazing Facts about the Brain

It Has 100 Billion Cells and a Quadrillion Synapses

Consciousness Doesn’t Reside in Any Specific Area of the Brain

It Has No Pain Receptors

Cutting the Largest Fiber Tract in the Brain Produces Few Side Effects

Einstein’s Brain Was Smaller than Average

Adults Lose Several Hundred Thousand Neurons a Day with No Noticeable Effect

Pound for Pound, It Takes a Lot of Energy

It’s a Myth That We Use Only 10 Percent of Our Brains

Brain Injuries Have Resulted in Savant Skills

Adult Brains Can Grow New Neurons

Chapter 21: Ten Promising Treatments for the Future

Correcting Developmental Disorders through Gene Therapy

Augmenting the Brain with Genetic Manipulation

Correcting Brain Injury with Stem Cells

Using Deep Brain Stimulation to Treat Neurological Disorders

Stimulating the Brain Externally through TMS and tDCS

Using Neuroprostheses for Sensory Loss

Addressing Paralysis with Neuroprostheses

Building a Better Brain through Neuroprostheses

Engaging in Computer-Controlled Learning

Treating Disease with Nanobots

About the Author

Connect with Dummies

End User License Agreement

Guide

Cover

Table of Contents

Begin Reading

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Introduction

The central mystery about the brain is simply this: How can a bunch of interconnected cells make each of us what we are — not only our thoughts, memories, and feelings, but our identity. At present, no one can answer this question. Some philosophers think it is not answerable in principle.

I believe we can understand how the brain makes us what we are. This book, while surely not containing the complete answer, points the way to what the answer looks like: In short, the brain is made of neurons, each of which is a complex little computer. Parts of the nervous system make suggestions to the rest of it about what you should do next. Other parts process the sensory inputs you receive and tell the system how things are going so far. Still other parts, particularly those associated with language, make up a running dialog about all of this as it is going on; this is your consciousness.

Those concepts aren’t too difficult to grasp, but people think of neuroscience as hard. And why? Because in order for your nervous system to perform these functions, it takes 100 billion neurons and a quadrillion connections structured over billions of years of evolution and all the human years of development and learning that resulted in who you are and where you are now.

You need to know three things to understand how the nervous system works. The first is how the neurons themselves work. The second is how neurons talk to each other in neural circuits. The third is how neural circuits form a particular set of functional modules in the brain. The particular set of modules that you have make you a human. The content of your specific modules make you unique.

Our nearest animal relative, the chimpanzee, has pretty much the same neurons and neural circuits that you and I do. They even have most of the same modules. We humans have a few extra modules that permit consciousness. Understanding this is what this book is about.

About This Book

Let’s face it. Neuroscience is a complex topic. How could it not be since it deals with the brain, the most complex structure in the known universe. In this book, I explain some very complex ideas and connections in a way that both students enrolled in introductory neuroscience courses and those who are just interested in the topic for fun can understand.

To use and understand this book, you don’t have to know anything about the brain except that you have one. In this book, I cover as much of the basics as possible with simple language and easy-to-understand diagrams, and when you encounter technical terms like anterior cingulate cortex or vestibulospinal reflex, I explain what they mean in plain English.

This book is designed to be modular for the simple reason that I want you to be able to find the information you need. Each chapter is divided into sections, and each section contains information about some topic relevant to neuroscience, such as

The key components of the nervous system: neurons and glia

How neurons work and what the different kinds of neurons are

What systems are involved in planning and executing complex actions

The role of the neocortex in processing thoughts

The great thing about this book is that you decide where to start and what to read. It’s a reference you can jump into and out of at will. Just head to the table of contents or the index to find the information you want.

Note: You can use this book as a supplemental text in many undergraduate courses because I discuss the neuron and brain function as a system. Typical undergraduate perception courses, for example, give short (and usually unsatisfactory) introductions to neurons and neural processing and little if any coverage of cognition. Cognitive psychology and neuroscience courses typically cover cognition well but often don’t ground cognition at the level of neurons. Behavioral neuroscience courses sometimes ignore cognition and neurophysiology almost altogether while doing a decent job explaining heuristics and phenomenology of behavior and learning. You can also use this book as an adjunct to graduate or health profession courses where the nervous system or mental illnesses or disorders are mentioned but little explicit coverage is given of the nervous system and the brain.

Within this book, you may note that some web addresses break across two lines of text. If you’re reading this book in print and want to visit one of these web pages, simply key in the web address exactly as it’s noted in the text, pretending as though the line break doesn’t exist. If you’re reading this as an e-book, you’ve got it easy — just click the web address to be taken directly to the web page.

Foolish Assumptions

In writing this book, I made some assumptions about you. To wit:

You’re not a professional neuroscientist or neurosurgeon but may be a beginning student in this field. (If you notice that your neurosurgeon thumbing through a copy of this book before removing parts of your brain, you might want to get a second opinion.)

You’re taking a course that relates to brain function, cognition, or behavior and feel that you would do better if you had a firm grasp of how the nervous system and its components work.

You want information in easy-to-access and easy-to-understand chunks, and if a little humor can be thrown in, all the better!

If you see yourself in the preceding points, then you have the right book in your hands.

Icons Used in This Book

The icons in this book help you find particular kinds of information. They include the following:

Looking at things a little differently or thinking of them in a new way can make potentially confusing concepts easier to understand. Look for this icon to find these “think of it this way” types of discussions.

This icon appears next to key concepts and general principles that you’ll want to remember.

In a subject as complicated as neuroscience, it’s inevitable that some discussions will be very technical. Fortunately for you, you don’t need to know the detailed whys and wherefores, but I include this info anyway for those who are voraciously curious or gluttons for punishment. Read or skip paragraphs beside this icon at will.

Beyond This Book

In addition to the material in the print or e-book you’re reading right now, this product also comes with some access-anywhere material on the web. The Cheat Sheet fills you in on types and function of cells in the central nervous system, the role of the neocortex, the left and right hemispheres of the brain, the brain’s four lobes, and more. To get this Cheat Sheet, simply go to www.dummies.com and type Neuroscience For Dummies Cheat Sheet in the Search box.

Where to Go from Here

Finally, the purpose of this book is to get you up to speed fast in understanding neurons and the nervous system, particularly the brain, but there are many important neuroscience topics that fall well beyond the scope of this book. Here’s just a sampling: intra-neuronal metabolism and second messenger cascades, association of neurological deficits with lesions in specific tracts and nuclei, traditional learning theory, and modern genetics. You can find detailed discussion of most of these subjects in Kandel, Schwartz, and Jessel’s Principles of Neural Science, 4th Edition (McGraw-Hill, 2000), the bible of neuroscience books.

Part 1

Introducing the Nervous System

IN THIS PART …

Discover what neurons are and what they do that allows 100 billion of them to make up a human brain.

See the overall structure of the central nervous system from the cortex to the brainstem and spinal cord.

Look at the details of neurons as electrical signaling devices that process inputs and secrete messenger molecules far away as their outputs.

Chapter 1

A Quick Trip through the Nervous System

IN THIS CHAPTER

Following the evolution of the nervous system

Understanding how the nervous system works

Listing the basic functions of the nervous system

Looking at types of neural dysfunction

Peeking into neuroscience’s future contributions

My brain: it’s my second favorite organ.

— WOODY ALLEN (SLEEPER, 1973)

The brain you are carrying around in your head is by far the most complicated structure known in the universe, and everything you are, have been, and will be arises from the activity of this three-pound collection of 100 billion neurons.

Although this book is about neuroscience, the study of the nervous system, it’s mainly about the brain, where most of the nervous system action takes place, neurally speaking. (The central nervous system consists of the brain, retina, and spinal cord.) If your brain functions well, you can live a long, happy, and productive life (barring some unfortunate circumstances, of course). If you have a brain disorder, you may struggle to overcome every detail of life, a battle that will take place within your brain. So read on for an introduction to the nervous system, how it works, what it does, and what can go wrong.