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How Our Brain Works How Our Brain Works Th e Construction and Functionality of Your Brain Presented and Explained DONALD A. MILLERS iUniverse, Inc. New York Bloomington Copyright © 2010 by Donald A. Millers All rights reserved. No part of this book may be used or reproduced by any means, graphic, electronic, or mechanical, including photocopying, recording, taping or by any information storage retrieval system without the written permission of the publisher except in the case of brief quotations embodied in critical articles and reviews. iUniverse books may be ordered through booksellers or by contacting: iUniverse 1663 Liberty Drive Bloomington, IN 47403 www.iuniverse.com 1-800-Authors (1-800-288-4677) Because of the dynamic nature of the Internet, any Web addresses or links contained in this book may have changed since publication and may no longer be valid. The views expressed in this work are solely those of the author and do not necessarily refl ect the views of the publisher, and the publisher hereby disclaims any responsibility for them. ISBN: 978-1-4502-0877-2 (sc) ISBN: 978-1-4502-0878-9 (ebook) Printed in the United States of America iUniverse rev. date: 03/05/2010 For my wife Janna and my daughters Traci and Samantha Contents Introduction ...................................................................... xiii Chapter 1 So You Want To Build A Brain You’re Going To Need Some Neurons ................................... 1 Brain Architecture ...................................................... 1 The Neuron (The Only Component Available for Building Brains).......................................................... 2 Conclusion (Pattern Detection - What Neurons Do) 13 Chapter 2 Your Brain Building The Basic Floor Plans .15 Introduction .............................................................. 15 A Tour of Your Nervous System ............................... 16 Neural Input – Building Your Virtual World ...............19 Floor #1 – The Spinal Cord (Your Brain’s Input / Output Channel) ...................................................... 35 Floor #2 – The Brain Stem (Your Reptilian Brain).... 37 Floor #3 - The Hypothalamus (Limbic System) and Thalamus ................................................................. 52 Floor #5 - The Cerebral Cortex (The Top Floor) ...... 57 Floor #4 – The Basal Ganglia (The Shipping Control Department) ............................................................. 73 Neural Output – (How You Control Your Skeletal Muscles) .................................................................. 81 Conclusion ............................................................... 87 Chapter 3 Lets Think About What The Brain Does ...... 88 Introduction .............................................................. 88 Memory .................................................................... 90 Learning ..................................................................93 Intelligence............................................................... 94 vii Language / Math ......................................................95 Consciousness ....................................................... 97 Right vs. Left Brain .................................................. 98 Sleep........................................................................ 98 Human Brain Evolution .......................................... 100 Conclusion ..............................................................110 Chapter 4 If Neurons Are The Solution, What’s The Problem? .......................................................111 Introduction .............................................................111 Neurons and Brains Evolved Together ...................113 Synchronization (The Case for Synchronization of Brain Activity) ..........................................................115 Neural Development (How You Grew Your Brain) ..117 Conclusion ............................................................. 128 Chapter 5 Human Brain Components Functional Analysis ........................................................ 131 Introduction ............................................................ 131 Neural Input ........................................................... 132 Somatosensory Input (How You Feel Your Environment) .................................................... 133 Visual Input (How You See Your World) ........... 139 Auditory Input (How You Hear Your World) ...... 155 Chemical Input (Taste and Smell) .................... 158 Balance ........................................................... 159 Component #1 – The Spinal Cord (Your Body’s Interface to Your Brain) .......................................... 159 Component #2 – The Human Brain Stem (Your Old Brain) ..................................................................... 162 Component #3 - The Cerebellum (Motor Output Memory) ................................................................. 174 Component #4 - The Hypothalamus and Your Limbic System ................................................................... 185 Component #5 – The Thalamus ............................ 188 Component #6 - The Cerebral Cortex ................... 194 viii Component #7 – The Basal Ganglia ...................... 214 Neural Output System (How You Control Your Skeleton)................................................................ 226 Conclusion ............................................................. 235 Chapter 6 Brain Architecture Analysis How Our Brain Works ............................................................ 236 Introduction ............................................................ 236 Neurons - Pattern Detection / Synchronous Activity ................................................................... 236 The Human Limbic System (Nature vs. Nurture) ...239 Your Declarative Memory System ........................ 242 Your Procedural Memory System ......................... 252 Brain Architecture ................................................. 258 Declarative Learning – Storing the Patterns of Your Virtual World .......................................................... 262 Procedural Learning – Storing the Patterns That Drive Your Behavior ........................................................ 267 Short-Term Memory .............................................. 269 Behavior - Thinking ................................................269 Language ............................................................... 270 Consciousness (Exactly Where in Your Brain Are You?) ..................................................................... 272 Conclusion ............................................................. 275 Index ....................................................................... 277 ix List of Illustrations Figure 1-1: Neuron .............................................................. 3 Figure 1-2: Axonal Action Potential .................................. 8 Figure 1-3: Types of Neurons ...........................................11 Figure 2-1: Central Nervous System (CNS).................... 17 Figure 2-3: The Retina ......................................................28 Figure 2-4: Visual Input Path ........................................... 30 Figure 2-5: The Spinal Cord ............................................. 36 Figure 2-6: The Brain Stem ..............................................38 Figure 2-7: The Cerebellum ............................................. 45 Figure 2-8: Cerebellar Layers .......................................... 47 Figure 2-9: Standard Cerebellar Circuit.......................... 48 Figure 2-10: Thalamic Nuclei ...........................................56 Figure 2-11: Hippocampus/Dentate ................................ 59 Figure 2-12: Hippocampus/Dentate Neural Wiring ........62 Figure 2-13: Cerebral Cortex ........................................... 64 Figure 2-14: Limbic Lobe ................................................. 66 Figure 2-15: Cerebral Cortex Layers............................... 69 Figure 2-16: Basal Ganglia .............................................. 76 Figure 2-17: Basal Ganglia Nuclei................................... 78 Figure 2-18: Neural Output System ................................ 85 Figure 5-1: Sensory Input Thalamic Nuclei ..................134 Figure 5-2: Somatosensory Cortex ...............................135 Figure 5-3: Somatosensory Input System.................... 137 Figure 5-4: Primary Somatosensory Cortex ................ 137 Figure 5-5: Lateral Geniculate Nucleus ........................ 142 Figure 5-6: Primary Visual Cortex .................................143 Figure 5-7: V1 Hypercolumn Structure .........................146 Figure 5-8: Secondary Visual Cortex ............................148 Figure 5-9: Superior Colliculus System ....................... 150 Figure 5-10: Auditory Input ............................................156 Figure 5-11: Primary Auditory Cortex ...........................157 Figure 5-12: Spinal Cord – Laminae ............................. 160 Figure 5-13: Medulla Oblongata – Schematic I ............ 164 xi Figure 5-14: Medulla Oblongata – Schematic II ........... 165 Figure 5-15: Pons – Schematic I ................................... 168 Figure 5-16: Pons – Schematic II .................................. 169 Figure 5-17: Midbrain – Schematic I ............................. 171 Figure 5-18: Midbrain – Schematic II ............................ 172 Figure 5-19: Cerebellar Circuitry ...................................177 Figure 5-20: Cerebellar
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