Anatomy & Physiology of
the Brain (Encephalon):
Preparing for ICD-10-CM/PCS
© Irene Mueller EdD, RHIA
May 2, 2013
Objectives

Review Brain Anatomy and Physiology for
ICD-10-CM/PCS Coding
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Overlap of Circulatory and Nervous Systems
Functions of Brain
Components of Brain
Cells of Brain
Brain Nerves
ICD 10 CM Terminology
 ICD 10 PCS Terminology


Integrated into presentation
Have you completed the Pre-Test????
Overlap of Circulatory and Nervous
Systems in Brain


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Connected through organ & bodily function control
All body functions are regulated by brain through
nervous system
 W/o messages from brain, circulatory system does
not work
 Heart function & fluid circulation triggered by
nervous system
 Messages sent from the brain control both blood
and lymphatic parts of circulatory system
Blood provides energy for brain


Brain = 2% of mass, uses 20% of energy
Avg weight of adult brain is about 3 pounds
Examples of Overlap in brain

Blood pressure and heart rate regulation



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Vagus nerve controls pumping of heart
As heart pumps, blood moves through blood
passageways around body to organs
Baroreceptors pass information about blood pressure to
brain so brain makes adjustments to heart rate
Dependent on each other to ensure
homeostasis


Nervous system may have control, but circulatory
system must relay information for adjustments
Both systems need to function properly & work together
to ensure proper body functions
Circulatory System Components of
Brain

Cerebral Arteries

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AKA Intracranical
Middle Cerebral
Anterior /Posterior
Communicating
Anterior/Posterior
Cerebral
Cerebellar
Other specified

Precerebral Arteries



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AKA Extracranial
Leading to cerebrum, but NOT
in cerebrum
Right vs Left for coding
Basilar artery
Carotid (Common, Internal)

External does NOT feed brain)

Vertebral

Other

Anterior spinal

Auditory internal
Circle of Willis



Basilar
Internal carotid
Vertebral artery
http://etc.usf.edu/clipart/15400/15496/bldbrnvessls_15496.htm
Functions of Brain


Control Center
of body
Maintains
homeostasis
(w/endocrine
system)
http://etc.usf.edu/clipart/8100/8171/human
_brain_8171.htm
Nervous System
Components of Brain

Nervous system = 2 parts

CNS = Brain and Spinal Cord (not part of this
webinar)

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Cerebrum, cerebellum, brain stem
PNS = Nerves and Ganglia
Somatic – connect CNS with skeletal muscles and
skin
 Autonomic – connect CNS with cardiac/smooth
muscle and glands

Cerebrum (L, brain)
Largest Part of brain
 Cortex = Gray Matter on surface
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6 layers of nerve cell bodies
Millions of cells
Cerebral White Matter



Under cortex
Myelinated axons of nerve cells
Transmit in 3 directions

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
Association = within same hemisphere
Commissural = from one hemisphere to other
Projection = from cerebrum to other parts of CNS
Functions of Cerebrum

3 general functions

Motor = Govern muscle movement

Sensory = Interpret sensory input
Vision = 30 % of cortex
 Touch =
8%
 Hearing = 3 %


Association = Emotional and
intellectual processes
Cortex


As brain grows, more gray
matter
Cortex folds on itself, creating


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Gyri (AKA convolutions) Gk, gyro,
circle
 Upfolds winding over surface
Fissures – Deep downfolds
Sulci –sulcus /sul·cus/ (sul´kus) pl.
sul´ci [L.] a groove, trench, or
furrow
 shallow downfolds separating
gyri
http://www.nlm.nih.gov/medlineplus/traumaticbraininjury.html
Hemispheres of Cerebrum

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Right and Left halves of brain
Divided by Longitudinal Fissure
Connected by Corpus Callosum



Large bundles of transverse nerve cell fibers
“Rain Man” – born w/o
Each hemisphere divided into 4 lobes


Frontal, Parietal, Temporal, and Occipital
Fifth lobe = Insula



Oval region of cerebral cortex overlying extreme capsule, lateral
to lenticular nucleus, buried in depth of the fissura lateralis
cerebri (sylvian fissure)
Separated from the adjacent frontal, parietal, and temporal
opercula by circular sulcus of insula.
Synonym(s): insular area, insular cortex, island of Reil
Corpus Callosum
L, - callous, hard
 AKA colossal commissure of brain


A tract of nerve fibers passing from one
side to other of spinal cord or brain
Larger in women
 Can transfer data between R & L
hemispheres faster than men


Woman’s intuition
Lobes of Cerebrum
http://en.wikipedia.org/wiki/Lobes_of_the_brain
Frontal Lobe Functions

Responsible for
higher cognitive
functions, including:
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Problem solving
Memory
Language
Judgment
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Spontaneity
Motivation
Impulse Control
Social and Sexual
Behavior
Temporal Lobe Functions
Role in emotions
 Responsible for

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Smelling
Tasting
Perception
Memory
Understanding music
Aggressiveness
Sexual behavior
Language areas of brain
Language areas of Brain

Broca’s area

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French surgeon, 1861
Frontal lobe
Motor neurons
Control of Speech
Wernicke’s area

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
German pathologist, 1874
Temporal lobe
Motor neurons
Comprehension of
Language, Speech sounds
http://wwwrohan.sdsu.edu/~gawron/intr
o/course_core/lectures/aphas
ia_cases_slides.html
Uncus
L. – uncus – hook From Gk onkos
 Hooklike anterior end of hippocampal
gyrus on temporal lobe of brain

Parietal Lobe Functions
Role in sensations of touch, smell, and
taste
 Processes sensory & spatial awareness
 Key part of eye-hand
co-ordination & arm movement
 Wernicke’s area


Matching written words to sound
of spoken speech
Occipital Lobe Functions

Controls vision and recognition

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Receives visual input from retina


Visual perception
Color recognition
Retina is part of brain
Visual signals are interpreted in occipital
lobes

Each optic nerve
has million fibers
Cerebellum





Sited below back of
cerebrum
Transverse fissure
separates from cerebrum
2 hemispheres separated
by vermis
Both gray and white
matter
Connected to brain stem
by cerebellar peduncles
(paired fiber bundles) http://etc.usf.edu/clipart/15500/15558/bra
inbase_15558.htm
Functions of Cerebellum
Motor area of brain
 Controls unconscious movements in
skeletal muscles
 Coordination, Posture, Balance

Brain Stem
Located below
cerebrum & in front of
cerebellum
 Structures
(from top to bottom)
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Thalamus
Hypothalamus
Midbrain
Pons
Medulla oblongata
http://birthinjury.org/brain-injury-cerebral-palsy-tour-of-brain.html
Thalamus (Gk: Inner Room)
Oval-Shaped, Large,
Located above midbrain
 Relays all sensory
impulses (EXCEPT smell)
to cerebral cortex
“Gateway”
 Interprets and produces
conscious Pain
recognition

Corpus striatum

Striped mass of white & grey matter
located in front of thalamus in each
cerebral hemisphere

Consists of caudate nucleus and lenticular
nucleus
Hypothalamus

Controls many homeostasis-related
body actions

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Interprets viscera-based sensory impulses

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Controls Body temperature
Regulates Biorhythms (Wake/Sleep)
ANS – heartbeat, food movement, urinary
bladder
Regulates food intake (Hunger/Satiety)
Regulates fluid intake (Thirst)
Monitors/Works with endocrine system
Responds to Mental states – Fear, etc.
Midbrain
Connects Pons and Cerebellum
 Short, Constricted
 Origination of 2 Cranial Nerves

III – Oculomotor
 IV - Trochlear

Pons (L. Bridge)
Located anterior to Cerebellum, above
Medulla
 Bridge between spinal cord & Brain
 Connects other parts of brain as well
 Origination for 4 cranial nerves

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V – Trigeminal
VI – Abducens
VII – Facial
VIII – Vestibulocochlear
Medulla oblongata
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
Lowest part of brain
Form upper part of Spinal Cord
Main Conduction Pathways

2 pyramids - ventral aspect

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Motor tracts from cortex to cord
Nerve fibers cross to other side
Extrapyramidal = functional, not
anatomical, unit comprising nuclei &
fibers (excluding pyramidal tract)
involved in motor activities;
control/coordinate especially postural,
static, supporting, & locomotor
mechanisms.
2 nuclei on dorsal aspect


Receive sensory impulses from spinal
cord (ascending)
Relay to OPPOSITE side of medulla

Origination for 4
cranial nerves




IX – Glossopharyngeal
X – Vagus
XI – Accessory
XII - Hypoglossal
Medulla oblongata, cont.

Reflex Centers
Cardiac – Regulates Heartbeat
 Respiratory – Rate and Depth
of Breath
 Vasoconstrictor – Regulates
Diameter of Blood Vessels

Cerebellar peduncles

3 sets of paired bundles of hindbrain,
connecting cerebellum to
Midbrain (superior)
 Pons (middle)
 Medulla oblongata (inferior)

Tapetum of brain
L. tapeta - a carpet
 Layer of fibers of corpus callosum forming
roof of part of lateral ventricle

Glands in the Brain

Pineal (L., Pine cone)

Pituitary

L. - pītuītārius pertaining to/secreting phlegm
Pineal Gland
Endocrine gland
 Source of melatonin

Hormone derived from tryptophan
 Regulates circadian rhythm (sleep cycle)


Located behind 3rd cerebral ventricle

Midline of brain
Pituitary Gland

Master gland


Central role in homeostasis,
maintaining reproductive cycle, directing activity of other
glands
Anterior, intermediate, and posterior lobes function as 3
separate endocrine organs


Distinct cell populations, secretory products, & regulatory
mechanisms
Anterior lobe secretes thyroid stimulating hormone,
corticotropin, luteinizing hormone, follicle stimulating hormone,
growth hormone, and prolactin.



Regulated by hypothalamus via portal vascular system
Posterior lobe releases oxytocin & vasopressin from axon
terminals originating in cell bodies located in hypothalamus
Intermediate lobe rudimentary in humans, but produces
several hormones (which are just now being studied).
Limbic System of Brain
Thalamus
 Hypothalamus
 Cingulate gyrus
 Amygdala
 Hippocampus
 Basal Ganglia

http://en.wikipedia.org/wiki/Lobes_of_the_brain
Limbic System Functions
Regulates emotion and memory
 Directly connects lower & higher brain
functions
 Influences

Emotions
 Visceral responses to emotions
 Motivation and Mood
 Sensations of pain and pleasure

Limbic System Components

Cingulate gyrus , L. - Girdle
(surrounding), Gk. - Circle

Amygdala, Gk. – Almond

(also used for tonsil)

Hippocampus, Gk. – seahorse

Basal Ganglia, Gk. - knot
Cingulate gyrus

Part of cerebrum gray matter


Surrounds, directly connected to parts of inner
Limbic System
Serves as conduit for messages to and
from inner Limbic System
Amygdala

Makes associations across different modes of
stimulus


Appears responsible for influence of
emotional states on sensory inputs



Smell of lilacs = visual memory of my house in
Great Falls
Same stimulus = Different perceptions
Sound of USAF Jets not noise – memory of
childhood
Responsible for face recognition?
Hippocampus

VERY important in transition of information
from short to long term memory
Search Engine of brain
 Learning and consciously remembering
everyday facts and events


Also part of Temporal Lobe

Damage to that lobe can result in memory
loss
Basal Ganglia
AKA Substantia nigra, Subthalmic nucleus
 Important in planning & coordinating
motor movements and posture
 Basal Ganglia linked with Cerebral Cortex
via complex neural connections
 Major effect of Basal Ganglia = Prevention
of unwanted muscular activity


Basal Ganglia Disorders result in
exaggerated, uncontrolled movements
Ventricles (Ependyma)




Network of connected
cavities filled with
cerebrospinal fluid
(CSF)
2 Lateral Ventricles
Third Ventricle
Cerebral Aqueduct


AKA Aqueduct of
Sylvius
Fourth Ventricle
http://emedicine.medscape.com/article/1923254-overview
Functions of Ventricles

Choroid plexuses located in ventricles produce
CSF, which fills ventricles & subarachnoid space


Cycle of production and re-absorption (toxic wastes)
Buoyancy, Protection, & Chemical stability



Protection = CSF in meninges protects brain from
striking cranium when head jolted
Buoyancy = CSF and brain have similar density, so
brain is suspended neutrally, allowing growth without
sitting on bone
CSF has protein, glucose, electrolytes, etc

500 ml per day, space for 130 ml in system
Meninges
Protect brain and spinal cord
 3 membranes




Dura mater = Outermost, tough, thick, fibrous
Arachnoid = Middle, delicate, fibrous
Pia Mater = Inner, transparent, tender



Contains blood vessels
Only layer that adheres to brain surface
Leptomeninges – 2 innermost; CSF
circulates between them

Gk – Small, thin
CELLS OF THE BRAIN
http://www.ninds.nih.gov/disorders/brain_basics/ninds_neuron.htm
Cells of Brain

100 billion neurons (nerve cells)



Sensory (afferent) – messages TO brain
Motor (efferent) – messages FROM brain
Trillions of Glia (Gk: Glue) (glial cells)



AKA Neuroglia
Connective tissue of brain
4 main types
Astrocytes, ependymal cells, microglia,
oligodentrocytes
 Common tumors of nervous system

3 classes of neurons
Sensory neurons carry information
from sense organs (such as eyes and
ears) to brain
 Motor neurons

control voluntary muscle activity (ex:
speaking)
 carry messages from nerve cells in brain to
muscles


All other neurons are Interneurons
Neurons - 3 basic parts

Cell body - includes nucleus, cytoplasm, and cell organelles




Dendrites


Nucleus =DNA & information needed for growth, metabolism, and repair
Cytoplasm = substance filling cell, including all chemicals/parts needed
for cell to work properly
Cell organelles = small structures (chromosomes, Golgi bodies, etc.)
http://library.thinkquest.org/12413/structures.html
Branch from cell body, act as point of contact for receiving impulses
(chemical/electrical signals) from neighboring neurons
Axon



Sends impulses, extends from cell body to meet/deliver impulses to
another nerve cell
Range in length from fraction of inch to several feet
Sciatic nerve axons extend from buttock to top of foot
Types of Glia cells
Microglia = Brain’s immune system
 Schwann cells/Oligodendrocytes form
insulating sleeves around neurons to keep
electric signals from diffusing (Myelin)
 Radial glia in developing brain




After helpng neurons move around
Then become astrocytes
Ependymal cells (ependymocytes)


Cells lining central canal of spinal cord (pyramidal
shape) or brain ventricles (cuboidal shape)
Produce/absorb/move (cilia) CSF
Myelin

Insulating material wrapped around axons





Complex mixture of proteins and fats
Nodes of Ranvier – gaps in myelin
Electrical signal jumps from node to node
Increases conduction speed of electrical signals
along nerve fibers to muscle
Made by Glial cells


Oligodendrocytes in CNS
Schwann cells in PNS
Transmission electron micrograph of a myelinated axon,
generated at the Electron Microscopy Facility at Trinity
College, Hartford, CT
http://frcables.blogspot.com/
Astrocytes

Have starlike rays


Reach out in all directions
Most abundant type of glial cells

So, most abundant of all brain cells
One astrocyte can wrap its rays around a
million+ synapses
 Astrocytes fuse together


Conduits for molecules moving from cell to
cell
Brain Waves



Cells in Cerebrum generate electrical potentials
Pass thru skull; Can be detected by electrodes
EEG = recording/graph of brain waves
http://en.wikipedia.org/wiki/Epilepsy



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
Beta - consciously alert, or feeling agitated, tense, afraid
Frequencies from 13 to 60 pulses/second in Hertz scale
Alpha - state of physical and mental relaxation, but aware of
surroundings
Frequencies around 7 to 13 pulses/second
Theta - state of somnolence w/reduced consciousness
+/- 4 to 7 pulses/second
Delta - unconsciousness, deep sleep or catalepsy
0.1 to 4 cycles/second
NERVES OF THE
BRAIN
Cranial Nerves
ICD-10-CM Index
I
uses numerical order (first,
fourth, etc), but also
provides names
III
ICD-10-PCS uses
NAMES only
II
V
IV
VI
VI
VIII AKA Auditory
IX
XII
X
Only First and Second
Cranial Nerves
originate in Cerebrum
http://en.wikipedia.org/wiki/Cranial_nerve
XI
Mnemonics for Cranial Nerves


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

On Old Olympus’ Towering Top A Famous Vocal German
Viewed Some Hops
On Old Olympic Towering Tops A Finn And German
Viewed Some Hops
OLd OPie OCcasionally TRies TRIGonometry And
Feels VEry GLOomy VAGUe And HYPOactive
Some Say Marry Money, But My Brother Says Big
Business Makes Money
Some say my mother bought my brother some bad beer,
my, my

S= Sensory, M = Motor, B = Both
Bonus Mnemonic for MS

Some Lovers Try Positions That They
Can't Handle!!!
Scaphoid, lunate, triquetrum, pisiform,
trapezium, trapezoid, capitate, hamate
Neurotransmitters

Chemicals that run brain
60+ affect memory, learning, relationships
 Thoughts, Food, Drugs affect brain chemicals

Stored in sacks near synapse at end of
axon
 Electrical charges from cell body free
chemicals, propel them across synapse
 Special receptors at end of dendrites form
to accept certain neurotransmitters

Important Neurotransmitters

Serotonin




Epinephrine
Aids in smooth transmission of
 Moving body when needs instant
action, - fear/danger
messages in brain/body
Large role in regulating mood,  Acetylcholine
 Enhances memory (chemical
appetite, memory & learning
responsible for many dreams)
Lack of serotonin may result in
low self-esteem, depression,  Endorphin (neuropeptide)
 Body’s natural pain killer -lots of
aggression
endorphin can create euphoric
feelings
Dopamine




Helps information flow to
higher brain levels
Key role in regulating
pain/pleasure
Melatonin

Related to wake/sleep cycles

Cortisol (neuropeptide)


Released when under stress
Can be dangerous at high levels –
interrupts transmission of
messages from neuron to neuron
Documentation Requirements for
Coding
Laterality
 Specific Arteries
 Site

Must use proximal branch for nerve that does not
have separate body part value in ICD-10-PCS
 Ex: mandibular nerve is branch of trigeminal
nerve, only the trigeminal nerve has a body part
value


When procedure performed on mandibular nerve, must
assign trigeminal nerve for body part value
Artery/Nerve Families, etc.
(ICD-10-PCS Body Key)

Alphabetical listing of body parts shows
PCS Description to use with Table Rows
when constructing a ICD-10-PCS code
Anatomical Term
PCS Description
Caroticotympanic artery
Internal Carotid Artery, R/L
Carotid sinus nerve
Glossopharyngeal nerve
Leptomeninges
Cerebral/Spinal meninges
Mammillary body
Hypothalamus
Middle cerebral artery
Intracranial artery
QUESTIONS?
Homework
1. Review Powerpoint before
taking post-test
2. Go online to at least two of the
Resource sites with Games
and/or Quizzes and see what
A&P about the brain you have
learned/reinforced
http://www.nimh.nih.gov/health/educational-resources/brain-basics/nimh-brain-basics.pdf
Resources

Amar AP, Weiss MH. Pituitary Gland Anatomy and Physiology.
Abstract. Neurosurg Clin N Am. 2003 Jan;14(1):11-23, v.


Anatomy of the Brain. American Association of Neurological
Surgeons.


http://www.theonlinelearningcenter.com/free-medicalgames/AP001/anatomy-physiology-brain-skull.html
Brain Anatomy. Game.


http://www.aans.org/Patient%20Information/Conditions%20and%20Tre
atments/Anatomy%20of%20the%20Brain.aspx
Anatomy of the Brain and Skull. Philips Medical Games.


http://www.ncbi.nlm.nih.gov/pubmed/12690976?report=abstract
http://www.purposegames.com/game/brain-anatomy-quiz
Brain Anatomy and Functions. Tutorial and Quiz. Getbodysmart.

http://www.getbodysmart.com/ap/nervoussystem/cns/brain/menu/menu.html
Resources




Cliff Notes. Anatomy & Physiology. Well-organized and includes
quizzes.
 http://www.cliffsnotes.com/study_guide/AnatomyPhysiology.topicArticleId-277792.html Cranial Nerves: Review
Info. Quizzes.
Cranial Nerves: Review Info
 http://www.gwc.maricopa.edu/class/bio201/cn/cranial.htm
Cranial Nerves Dirty Mnemonic Tutorial. Video.
 http://www.youtube.com/watch?v=LTUHTxWG6EQ
Crisan, E. Ventricles of the Brain. Jun 27, 2011. Medscape
Reference.
 http://emedicine.medscape.com/article/1923254-overview
Resources





Division of Disability and Aging Services. Vermont. Brain 101: The
neurotypical brain.
 http://www.ddas.vermont.gov/ddas-policies/policies-tbi/policies-tbidocuments/tbi-trng-modules-workbks/training-module-1-brain-101
Gray, H. Anatomy of the Human Body. 1918.
 http://www.bartleby.com/107/
Human Brain Anatomy. Study and Quiz Modules.
 http://www.psych.ualberta.ca/~ITL/brain/
Interactive Tour of the Brain. National Brain Tumor Society.
 http://www.braintumor.org/patients-family-friends/about-braintumors/index8.html
Intro to the Brain. ITS. San Diego State Univ. Includes Test.
 http://its.sdsu.edu/multimedia/mathison/index.htm
Kean, M. L. The Brain. Tutorial.
 http://wwwrohan.sdsu.edu/~gawron/intro/course_core/lectures/aphasia_cases_s
lides.html
Resources
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Match a Brain. Game.
 http://www.anatomyarcade.com/games/matchingGames/MatchA
Brain/matchABrain.html
McGuire, N. ICD10 Session 11 Chapter 6. Codapedia. 32 Minute
video.
 http://codapedia.com/article_548_ICD-10-Session-11-ChapterSix-Diseases-of-the-Nervous-System.cfm
Neuron-Glia Interactions in Nerve Development and Disease.
 http://www.ngidd.eu/public/index.html
NIMH. Brain Basics.
 http://www.nimh.nih.gov/health/educational-resources/brainbasics/brain-basics.shtml
Pineal Gland. Encyclopedia Brittanica.
 http://www.britannica.com/EBchecked/topic/460967/pineal-gland
Resources
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Secret Life of the Brain. PBS. 3-D brain anatomy.
 http://www.pbs.org/wnet/brain/history/index.html
Tamarkin, D. A. Glia.
http://faculty.stcc.edu/AandP/AP/AP1pages/nervssys/unit10/glia.htm
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University of Bristol. How the Brain Works. Video, 6+ min. 2010.

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WebMD. Brain & Nervous System Health Center.


http://www.webmd.com/brain/default.htm
WebMD. Medical References Related to Brain & Nervous System.


http://www.youtube.com/watch?v=9UukcdU258A
http://www.webmd.com/brain/medical-reference-index
Wernicke area. Encyclopedia Britannica. Videos, Animations.

http://www.britannica.com/EBchecked/topic/639879/Wernicke-area