The Brains Inner Workings

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The Brains Inner Workings
Complexity of the Brain Imaging the Brain NIMH
Research on the Brain and Mental Illness
NAMI Ohio/ NIMH Outreach
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Brain Trivia
The adult brain weighs about 3 pounds.
The average number of neurons in the brain 100
billion.
A newborn babys brain is as soft and gooey as
tapioca pudding!
The average number of glial cells in the brain
10-50 times the number of neurons.
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Complexity of the Brain
one hundred trillion synapses in a single human
brain organized into exquisitely complex
circuits responding to experience,
drugs, disease, and injury
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Complexity of the Brain
As befits the 3-pound organ of the mind, the
human brain is the most complex structure ever
investigated by our science.
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Complexity of the Brain
The brain contains approximately 100 billion
nerve cells, or neurons, and 10 50 times more
supporting cells, or glia.
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Complexity of the Brain
The workings of the brain depend on the ability
of nerve cells to communicate with each other.
Communication occurs at small, specialized
structures called synapses.
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Nerve Cell Communication
Synapse
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Complexity of the Brain
The synapse typically has two parts
and a postsynaptic structure on the dendrites of
the receiving neuron that has receptors for the
neurotransmitter molecules.
A presynaptic structure containing packets of
signaling chemicals, or neurotransmitters
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Complexity of the Brain
One of the most awe-inspiring mysteries of
brain science is how neuronal activity within
circuits gives rise to behavior, and
even consciousness Mental Health A Report of
the Surgeon General
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The Cerebral
Hemispheres The brain consists of two
hemispheres. The Left Hemisphere of the Brain
The left hemisphere processes information
sequentially and is described as analytical
because it specializes in recognizing parts which
make a whole. Although it is most efficient at
processing verbal information, language should
not be considered as being 'in' the left
hemisphere. This hemisphere is able to recognize
that one stimulus comes before another and verbal
perception and generation depends on the
awareness of the sequence in which sounds occur.

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The Cerebral
Hemispheres The brain consists of two
hemispheres. The Right Hemisphere While the
left hemisphere separates out parts that make a
whole, the right hemisphere specializes in
combining the parts to produce a whole. Unlike
the left, the right hemisphere organizes
simultaneously. It specializes in a method that
perceives and constructs patterns. It is most
efficient at visual and spatial processing and it
is thought that non verbal stimuli are processed
primarily in the right hemisphere. Research into
the operation of the right and left hemispheres
shows that the effective processing of
information requires access to both as they
complement each other.
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It is useful to think of the brain as containing
six or seven component parts. The largest and
most advanced part consists of the left and right
cerebral hemispheres, which appear to be more or
less symmetrical. They are covered with a layer
of gray matter called the cerebral cortex. Each
of the cerebral hemispheres has traditionally
been divided into four "lobes," which are named
after the bones of the skull that surround them
frontal, parietal, occipital, and temporal.
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The entire outer surface of the brain is called
the cortex, with the forebrain area called the
frontal cortex. Those brain structures lying
underneath the cortex are termed subcortical.
Two sites of great interest in current brain
research are the left frontal cortex and the
left temporal subcortical areas, both of which
are linked to key parts of the basal ganglia and
the limbic system within the brain. In research
language, these are the cortico-limbic and
tempero-limbic circuits in the brain.
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The frontal lobe is the largest and least
understood, beginning at the front of the brain
and reaching back to the central sulcus. The
area between the central and precentral sulci
helps control body movements and is called the
"motor area," while the remainder of the frontal
lobe probably modulates various aspects of
thinking, feeling, imagining, and making
decisions.
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The Frontal Cortex is the highest and most
complex integration center in the human brain
the essential function area for "volition," i.e.,
planning and carrying out meaningful, goal
directed activities. Lesions in the left frontal
cortex create deficits in attention, abstract
thinking, foresight, mature judgment, integration
of thought and perception, reality testing,
initiative, and perseverance and induce a state
of pseudo-depression characterized by apathy,
lack of motivation, withdrawal, and loss of
sexual interest. Lesions in the right lobe have
a disinhibiting effect, revealed in wide mood
swings, immature behavior, irresponsibility,
inappropriate sexual behavior and/or
hypersexuality.
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The parietal lobe is the region behind the
central sulcus. Part of it is called the
"somatosensory area," since it receives
information about various bodily sensations the
parietal lobe also modulates such activities as
spatial orientation. The occipital lobe recieves
and sends out visual information. The temporal
lobe is perhaps the most conspicuous lobe of the
brain since it juts out from the rest and is
demarcated by the very deep Sylvan fissure. The
temporal lobe receives auditory information and
controls memory and language.
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Complexity of the Brain
The specific connectivity of circuits is, to some
degree, set in expected patterns within the
brain, leading to the notion that certain places
in the brain are specialized for certain
functions.
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Frontal Lobe Motor Behavior
Parietal Lobe Processing of Tactile Information
Occipital Lobe Visual Processing
Prefrontal Cortex Ability to plan integrate
cognitive and emotional information
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Mapping the Mind
Personality traits from shyness to impulsiveness,
scientists believe, are produced by particular
brain molecules acting on specific brain
structures. Through brain mapping and
biochemistry, researchers have identified some
of them.
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Subcortical Structures of the Limbic System

• These brain areas are closely connected in
  structure and function. Pathology in
  schizophrenia and other major mental illnesses is
  thought to lie somewhere in the complex
  interconnections in the limbic system.

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Mental Disorders
Mental disorders are characterized by
abnormalities in cognition, emotion (or mood), or
behavior, such as social interactions or planning
of future activities. Symptoms related to
behavior or our mental lives clearly reflect
abnormalities in brain function.
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Viewing Disorders in Action
One of the major areas in which molecular
genetics will play an important role in the
future is in complex disorders like schizophrenia
and depression. The figure shows areas of
increased blood flow (red hotspots) in the left
amygdala and the medial orbital cortex of a
person with familial (inherited tendencies
to) major depressive disorder.
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MRI
Magnetic resonance imaging provides a high
resolution image of the brain's internal
structure. The scanner contains a large magnet
that induces different chemical elements to emit
distinctive radio signals.
The signal data is translated into 2-D pictures
of the brain, slice by slice. These data can also
be combined to create 3-D views. MRI is an
important tool in studies of mental illnesses
that may involve structural changes, such as
schizophrenia and ADHD.
Functional Magnetic resonance imaging (fMRI) is a
powerful tool for studying the ever-changing
activity of the brain on a moment to moment
basis. Once limited to visualizing structures,
MRI has become the leading technology for
examining the living brain at work.
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PET Positron Emission Tomography is a brain
imaging technique that uses a radioactive tracer
to show chemical activity of the brain. The PET
scanner pinpoints the destination of
radioactively tagged glucose, oxygen, or drugs to
reveal the parts of the brain involved in
performing an experimental task.
PET allows us to look at brain functions by
measuring levels of energy - or activity - in
specific areas of the brain. PET scans generate
pictures of the working brain, providing maps of
emotions, learning, vision, and memory.
Identifying these brain functions is key in
developing new ways to diagnose and treat
schizophrenia and other mental disorders.
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This image shows different PET scans of a
forty-five-year- old woman with recurrent
depression.
The scan on the left was taken when she was on no
medications and very depressed. The scan on the
right was taken several months later when she was
well, after medication had treated her
depression. Note that her entire brain is more
active when well, particularly the left
prefrontal cortex.
Identifying brain activity associated with
depression and the changes that result from
treatment and the patient's improved mood will
help to destigmatize the illness, a disease of
the brain.
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The Invisible Disease
Depression
One man in ten and one woman in five will have a
serious depression in their lives, usually
before they are 40 years old.
Bipolar disorder (manic-depression) occurs in
1.2 of the population. The majority of
individuals with this illness report having
symptoms during their adolescence.
Suicide is a very high risk for this population.
Tragically, 15 of those individuals suffering
from recurrent depressive disorders kill
themselves. This is a suicide rate 30 times
greater than that of the general population.
Most people with depression can be helped with
treatment. But a majority of depressed people
never get the help they need. And when depression
isnt treated, it can get worse, last longer, and
prevent you from getting the most out of life.
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Depression
Depression is believed to result from a
chemical imbalance in the brain.
Antidepressant drug therapy may help restore that
chemical balance and relieve depression .
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You should get evaluated by a professional if
youve had five or more of the following symptoms
for more than 2 weeks or if any of these symptoms
cause such a big change that you cant keep up
your usual routine
Depression
1. You feel sad or cry a lot and it doesnt go
away.
2. You feel guilty for no reason you feel like
youre no good youve lost your confidence.
3. Life seems meaningless or like nothing good is
ever going to happen again. You have a negative
attitude a lot of the time, or it seems like you
have no feelings.
4. You dont feel like doing a lot of the things
you used to enjoy - and you want to be left
alone most of the time.
5. Its hard to make up your mind. You forget
lots of things, and its hard to concentrate.
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You should get evaluated by a professional if
youve had five or more of the following symptoms
for more than 2 weeks or if any of these symptoms
cause such a big change that you cant keep up
your usual routine
Depression
6. You get irritated often. Little things make
you lose your temper you over-react.
7. Your sleep pattern changes you start sleeping
a lot more or you have trouble falling asleep at
night. Or you wake up really early most mornings
and cant get back to sleep.
8. Your eating pattern changes youve lost your
appetite or you eat a lot more.
9. You feel restless and tired most of the time.
10. You think about death, or feel like youre
dying, or have thoughts about committing suicide.
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If Youre Manic
Some of these sound like you -
1. Youre rebellious or irritable and cant get
along at home, school, work, or with your
friends.
2. You feel high as a kitelike youre on top of
the world.
3. You get unreal ideas about the great things
you can do.
4. Thoughts go racing through your head, you jump
from one subject to another, and you talk a lot.
5. Youre a non-stop party, constantly running
around.
6. You do too many wild or risky things with
driving, with spending money, with sex, etc.
7. Youre so up that you dont need much sleep.
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Schizophrenia
These are MRI scans of identical twins. The twin
on the right has schizophrenia the twin on the
left is healthy. Even to the unprofessional eye,
there are obvious differences, a systematic and
consistent variation between the affected and the
unaffected twin in the gross anatomy of the
brain. (Note enlarged ventricles in the twin
affected with schizophrenia) Source E. Fuller
Torrey, M.D., Daniel R. Weinberger, M.D.
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Schizophrenia
Schizophrenia, in many ways, is the most severe
of the mental illnesses. One in every one hundred
Americans has schizophrenia. This disease, once
thought to be psychological, is clearly a brain
disease. Throughout the world, whether in
Washington or New York City or in rural Kenya,
the rate of schizophrenia is still the same one
percent of the population. Schizophrenia is a
brain disease in which vulnerability is caused by
genes something happens during brain development
that converts this genetic vulnerability into
disease. Exactly what happens is the subject of
neuroscientific research.
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Schizophrenia
In some ways, schizophrenia is like other
diseases. People who develop diabetes or heart
disease have a genetic vulnerability, and then
external circumstances convert this vulnerability
into disease. Rather than being unusual and
mysterious entities, mental illnesses are real
diseases of an organ - in this case, the brain.

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Schizophrenia
Schizophrenia is particularly tragic because its
onset usually occurs in the late teens or early
20s, just when families, society, and educational
institutions have already put their full effort
into launching a person into the world.
Tragically, then, we lose them, often to chronic
and persistent hallucinations and delusions,
fixed false beliefs about the world, and an
inability to live up to their potential often
they withdraw from society and lose their ability
to cope with everyday life.
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Schizophrenia
Many of the symptoms of schizophrenia are
believed to be caused by excess dopamine. Reduced
glutamate transmission which blocks the NMDA
restraining action causing limbic structures to
release more and more dopamine could be the
ultimate cause.
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Step On A Crack-
About 2.3 of the U.S. population ages 18-54
(approximately 3.3 million) has
obsessive-compulsive disorder in a given year.
OCD
People with OCD suffer intensely from recurrent,
unwanted thoughts (obsessions) or rituals
(compulsions), which they feel they cannot
control. Rituals, such as handwashing, counting,
checking, or cleaning are often performed in hope
of preventing obsessive thoughts or making them
go away. Performing these rituals, however,
provides only temporary relief, and not
performing them markedly increases anxiety. Left
untreated, obsessions and the need to perform
rituals can take over a persons life. OCD is
often a chronic, relapsing illness.
OCD affects men and women equally.
OCD typically begins during adolescence or early
childhood at least one-third of the cases of
adult OCD began in childhood.
OCD cost the U.S. 8.4 billion in 1990 in social
and economic losses, nearly 6 of the total
mental health bill of 148 billion.
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Persons with OCD use different brain circuitry
in performing a cognitive task than people
without the disorder. Rauch SL, et al. J
Neuropsychiatry Clin Neurosci, 1997 9568-573.
There is growing evidence that OCD has a
neurobiological basis. The search for causes now
focuses on the interaction of neurobiological
factors and environmental influences. Brain
imaging studies using PET scans have compared
people with and without OCD. Those with OCD have
patterns of brain activity that differ from
people with other mental illnesses or people with
no mental illness at all. PET scans also show
that both behavioral therapy and medication
produce changes in the caudate nucleus. This is
graphic evidence that both psychotherapy and
medication affect the brain.
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This presentation produced by Velma Beale, Ohio
NIMH Outreach Coordinator, NAMI Ohio, with
materials from Mental Health A Report of the
Surgeon General the NIMH website and
publications and the NAMI Family-to-Family
education course.
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For Further Information
Visit these websites http//www.nami.org
http//www.nimh.nih.gov http//www.namiohio.
com E-mail Ohio NIMH Outreach Coordinator
Velma.Beale_at_axom.com NAMI Ohio
amiohio_at_amiohio.org NIMH nimhinfo_at_nih.gov Or
call the Ohio NIMH Outreach Coordinator
740-599-5266 NAMI Ohio 614-444-AMIO NAMI
Ohio hotline (in Ohio) 1-800-686-AMIO