Download October / November 2008 - St. Joseph`s Health Care London

The Family Forum
Newsletter of the Family Advisory Council
October / November 2008 (Vol. 4, Issue 4)
PSYCH 101
The Human Brain
Parts of the Brain
The human brain: an incredible machine. Containing
15 billion cells, 100 billion neurons, 0.85 litres of
blood, and 150 ml of cerebrospinal fluid, it’s a wonder
it can fit inside your head. The brain weighs about
three pounds and has a surface area of about 2.5
square feet. You might wonder how a brain with an
area of two and a half square feet does indeed fit
inside your skull. Imagine trying to stuff a sheet of
newspaper into a coffee cup. The only way to fit it in
is to crumple it up, creating folds. The surface area is
still the same but it takes up much less space.
Likewise, your brain is “crumpled”, folded so that the
maximum area can be used.
Did you know?
The dimensions of the adult brain are about
140mm x 170mm x 95mm.
The cerebrum (the thinking part) makes up about
90% of the brain.
Your brain makes up about 2% of your total body
weight.
The energy used by the brain is enough to light a
25-watt bulb.
There are about the same number of neurons in
your brain as there are stars in the sky.
The composition of the brain is 78% water.
About 3 pop cans full of blood flow through the
brain every minute.
The brain can survive for 4 to 6 minutes without
oxygen.
A human brain usually thinks about 70,000
thoughts a day.
After age 30, the brain shrinks a quarter of a
percent (0.25 %) in mass each year.
Cerebrum - The cerebrum is composed of the right
and left hemispheres. Functions of the cerebrum
include: initiation of movement, coordination of
movement, temperature, touch, vision, hearing,
judgment, reasoning, problem solving, emotions, and
learning.
Brainstem - The brainstem includes the midbrain,
the pons, and the medulla. Functions of this area
include: movement of the eyes and mouth, relaying
sensory messages (hot, pain, loud, etc.), hunger,
respirations, consciousness, cardiac function, body
temperature,
involuntary
muscle
movements,
sneezing, coughing, vomiting, and swallowing.
Cerebellum - The cerebellum is located at the back
of the head. Its function is to coordinate voluntary
muscle movements and to maintain posture, balance,
and equilibrium.
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Pons - A deep part of the brain, located in the
brainstem, the pons contains many of the control
areas for eye and face movements.
Medulla - The lowest part of the brainstem, the
medulla is the most vital part of the entire brain and
contains important control centers for the heart and
lungs.
Frontal Lobe - The largest section of the brain
located in the front of the head, the frontal lobe is
involved in personality characteristics and movement.
Parietal Lobe - The middle part of the brain, the
parietal lobe helps a person to identify objects and
understand spatial relationships (where one's body is
compared to objects around the person). The parietal
lobe is also involved in interpreting pain and touch in
the body.
Occipital Lobe - The occipital lobe is the back part of
the brain that is involved with vision.
Temporal Lobe - The sides of the brain, these
temporal lobes are involved in memory, speech, and
sense of smell.”
http://www.childrenshospital.org/az/Site570/printerfrie
ndlypageS570P0.html
Lobes of the Brain
Frontal lobe –
having to do with
decision making,
problem solving
and planning
Temporal
lobehaving to
do with
memory,
emotions,
hearing
and
language
Parietal lobe –
concerned with the
reception and
processing of sensory
information from the
body
Occipital lobe
–concerned
with vision
understanding language. The cerebral cortex can be
divided into areas that each have a specific function.
For example, there are specific areas involved in
vision, hearing, touch, movement, and smell. Other
areas are critical for thinking and reasoning.
Information from:
http://www.teens.drugabuse.gov/mom/tg_brain.asp
How Does It All Work
The basic building block in the brain is the neuron
(see diagram on next page). We each have billions
of them. Whenever we feel emotions, think, or act,
our neurons send messages from one cell to another.
Within the brain, there are special chemicals called
neurotransmitters that carry these messages.
The cells communicate using chemical and electrical
impulses. Within a neuron, information is passed by
an electrical current whereas chemical messages are
sent through the gaps or synapses between the
neurons. A neuron has four basic parts: the cell
body, the axon, the dendrites, and the axon
terminals. An electrical impulse travels from the
receiving dendrites, through the cell body, and along
the axon to the axon terminals. Neurons do not
actually touch; instead there are fluid-filled gaps,
called synapses, between them.
The electrical
current cannot pass through the synapse so it is
converted to a chemical message. The chemical
messengers are neurotransmitters.
The neurotransmitters are molecules that move through the
synapse to the dendrites of the next neuron, passing
along the message. Then the message once again
becomes an electrical impulse and the process is
repeated.
Once used, these molecules are either broken down
by an enzyme (i.e. monoamine oxidase) or
reabsorbed by the neuron in a process called
reuptake.
While there are more than 30 neurotransmitters,
there are only a few that are associated with the
major mental illnesses.
Neurotransmitters:
This drawing of a brain cut in half shows the lobes of
the cerebral cortex and their functions.
Acetylcholine (ACTH): Important for memory. It also
lowers blood pressure and reduces cholesterol. Too
much acetylcholine is associated with depression and
too little has been associated with dementia.
The cerebral cortex is divided into right and left
hemispheres. It makes up about two-thirds of the
human brain mass and lies over and around most of
the other parts of the brain. It is the most highly
developed part of the human brain and is responsible
for thinking, perceiving, and producing and
Dopamine: Gives us our sense of pleasure and
motivation by regulating the release of endorphins. It
improves mood, sex drive and memory. People with
low levels of dopamine often try to compensate
through caffeine, sugary foods, cigarettes, alcohol
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and other drugs, which also induce the release of
endorphins, or activities like gambling, work or
exercise. Too much dopamine has been associated
with schizophrenia and too little is associated with
depression and Parkinson’s disease.
The Neuron
Dendrites
Cell Body
Endorphins: Natural painkillers released by
exercise. Several studies have shown that they can
also be released when we listen to music with a
strong beat. Endorphins are involved in pain relief
and feelings of pleasure and contentedness.
GABA: Needed for sleep and relaxation, as well as
enabling us to withstand cravings. People with low
levels of GABA, including alcoholics and other
addicts, can be tense, anxious and aroused to anger
with little provocation. Too little GABA is associated
with
anxiety
disorders.
Axon
Axon
Terminals
Glutamate: Facilitates long-term learning and
retention. It also plays a role in our tolerance for pain.
GABA balances glutatamate’s effects in the brain.
from: : www.utsa.edu/tsi/2000tsi/people/Junek
Norepinephrine: A hormone that acts like a
neurotransmitter and is released in response to low
blood pressure. It enhances our memory, makes us
more alert and gives us a sense of power and
control. Too little norepinephrine is associated with
depression while an excess has been associated with
schizophrenia.
Serotonin: The body’s natural tranquilizer, it relaxes
us, regulates body temperature and appetite, sets our
internal clock for sleep, and makes us feel peaceful
and contented. It also acts as a natural
counterbalance to dopamine. People with low levels
of serotonin tend to act rashly and aggressively and
to become easily depressed. Too little serotonin is
associated with depression and some anxiety
disorders, especially obsessive-compulsive disorder.
From:
http://www.alive.com/4133a8a2.php?subject_bread_c
ramb=80
Neurotransmitter Transmission
http://bipolar.about.com/cs/neurotrans/l/aa0007_msn
grs.htm?rd=1
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Diagnosis of Psychiatric Disorders
The Diagnostic and Statistical Manual of Mental
Disorders, (DSM-IV), published by the American
Psychiatric Association, is used by qualified mental
health professionals to make a diagnosis of a mental
illness. Sections on the various illnesses list
symptoms of each. A person must meet a particular
number of criteria in order to be diagnosed with a
disorder. However, remember that only a qualified
professional who also relies on clinical judgment can
make such a diagnosis.
For example:
The following is the diagnostic criteria (symptoms) for
Generalized
Anxiety
Disorder.
A) At least 6 months of "excessive anxiety and
worry" about a variety of events and situations.
Generally, "excessive" can be interpreted as more
than would be expected for a particular situation or
event…
B) There is significant difficulty in controlling the
anxiety and worry. If someone has a very difficult
struggle to regain control, relax, or cope with the
anxiety and worry, then this requirement is met.
C) The presence for most days over the previous six
months of 3 or more (only 1 for children) of the
following symptoms:
1.
2.
3.
4.
5.
6.
Feeling wound-up, tense or restless
Easily becoming fatigued or worn-out
Concentration problems
Irritability
Significant tension in muscles
Difficulty with sleep
D) The symptoms are not part of another mental
disorder.
E) The symptoms cause "clinically significant
distress" or problems functioning in daily life.
"Clinically significant" is the part that relies on the
perspective of the treatment provider. Some people
can have many of the aforementioned symptoms and
cope with them well enough to maintain a high level
of
functioning.
F) The condition is not due to a substance or medical
issue
Classifying Psychopathology
To get an impression of the “Big Picture”, a diagnosis
is made using a multiaxial or multidimensional
approach. Typically, other factors in a person's life
impact their mental health. The process of diagnosis
assesses the five dimensions described below:
Axis I: Clinical Syndromes
• This is what we typically think of as the diagnosis
(e.g., depression, schizophrenia, social phobia)
Axis II: Developmental Disorders and Personality
Disorders
• Developmental disorders include autism and
mental retardation, disorders which are typically
first evident in childhood
• Personality disorders are clinical syndromes,
which have more long lasting symptoms and
encompass the individual's way of interacting
with the world.
They include Paranoid,
Antisocial, and Borderline Personality Disorders.
Axis III: Physical Conditions which play a role in
the development, continuance, or exacerbation of
Axis I and II Disorders
• Physical conditions such as brain injury or
HIV/AIDS that can result in symptoms of mental
illness are included here. (Often, all of a person’s
physical diagnoses are listed here.)
Axis IV: Severity of Psychosocial Stressors
• Events in a person’s life, such as death of a loved
one, starting a new job, college, unemployment,
and even marriage can impact the disorders
listed in Axis I and II. These events are both
listed and rated for this axis.
Axis V: Highest Level of Functioning
• On the final axis, the clinician rates the person's
level of functioning both at the present time and
the highest level within the previous year. This
helps the clinician understand how the above four
axes are affecting the person and what type of
changes could be expected.
Source: American Psychiatric Association (2000). Diagnostic and
Statistical Manual of Mental Disorders (4th Ed., Text Revision).
Washington DC: American Psychiatric Association.
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Mechanisms of Different Disorders - and
the Medications That Treat Them
psychiatric medications can be prescribed to return
your neurotransmitter levels to normal.
Researchers have been interested in a particular part
of the brain called the limbic system. This is the area
of the brain that regulates activities such as
emotions, physical and sexual drives, and the stress
response. There are various structures of the limbic
system that are of particular importance. The
hypothalamus is a small structure located at the base
of the brain. It is responsible for many basic functions
such as body temperature, sleep, appetite, sexual
drive, stress reaction, and the regulation of other
activities. Other structures within the limbic system
that are associated with emotional reaction are the
amygdala and hippocampus. The activities of the
limbic system are so important and complex that
disturbances in any part of it, including how
neurotransmitters function, could affect your mood
and behavior.
Medications for mental health conditions work in
several ways:
A network of neural pathways connects to the
neocortex, the "thinking brain," allowing us to reflect
on our feelings and to think before acting. In times of
perceived crisis, however, those pathways are
bypassed and impulse overrides reason. Sometimes,
emotions and their physiological effects can seem
indistinguishable.
Each emotion sparks a distinctive physiological
reaction, the body’s program for dealing with the
different situations that arise in our emotional lives.
According to the American Medical Association,
stress contributes to 75 per cent of all cases of illness
in the United States. However, it is both physiological
effects of emotions and how we deal with them that
affect our overall health.
Neurotransmitters are chemicals that send messages
within the brain to regulate our mental and bodily
functions. Emotions or emotional behaviour can
trigger their release.
Studies usually show a correlation or link between
the neurotransmitter and the development of mental
disorders.
Understanding
the
nature
of
neurotransmitters
provides
a
window
to
understanding the majority of psychiatric conditions,
ranging from depression to schizophrenia. Mental
health professionals use psychological testing,
interviews, questionnaires, and patient history to
make a clinical diagnosis, which then leads to proper
treatment.
· Some imitate the neurotransmitter, triggering a
response as though the original neurotransmitter
were present
· Some block the neurotransmitter from being
absorbed by the surrounding neurons, known as
blocking the reuptake. Reuptake inhibitors block the
reabsorption/reuptake of Serotonin or Norepinephrine
and thus make more neurotransmitter available. For
example Cocaine blocks the reuptake of dopamine
and, to a lesser extent, serotonin and norepinephrine.
· Some force the release of the neurotransmitter,
causing an exaggerated effect. MDMA (Ecstasy – a
club drug) does this to Serotonin.
· Some increase neurotransmitters known to slow
down or reduce the production of other
neurotransmitters.
· Some block the release of neurotransmitters
completely.
·
Some
interfere
with
the
storage
of
neurotransmitters, allowing them to come out of
storage and lose potency.
Information from:
http://www.alive.com/4133a8a2.php?subject_bread_c
ramb=80#top
http://www.allaboutdepression.com
http://www.enotalone.com/article/4119.html
Anxiety
Anxiety is related to the neurotransmitter GABA,
which is the brain’s “quieting” or calming
neurotransmitter. Benzodiazepines (i.e. Valium) and
other related drugs enhance the effect of GABA.
When one suffers from an anxiety disorder, the brain
becomes overactive and it needs the transmitters
associated with quieting the brain to come into action.
These respond by sending messages to the brain
cells telling it to slow down.
These drugs are effective but can be addictive so are
usually recommended for short-term use only.
Medications are prescribed in an effort to return the
brain’s neurotransmitter status to normal. Much like a
physician may prescribe a medication to lower your
cholesterol or increase another body chemical,
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Depression
Schizophrenia
Depression is associated with low levels of the
tranquilizing
neurotransmitters
serotonin
and
norepinephrine. The sending neuron releases its
neurotransmitters to send the message. Once the
neurotransmitter has delivered its message, it should
be reabsorbed (in a process called reuptake) so that
it can be reused. In depression, the rate and
efficiency of this re-absorption result in a shortage of
neurotransmitters in the synapses.
Medications used to treat depression work to
increase the amount of these neurotransmitters,
usually by blocking or inhibiting the reuptake. There
are two main classes of anti-depressant medications:
Selective Serotonin Reuptake Inhibitors (SSRI’s),
such as Prozac, and Tricyclic Antidepressants, such
as Amitriptyline or Nortriptyline. Monoamine Oxidase
Inhibitors (MAOI’s) are an older class of
antidepressants that work by slowing down the
neurotransmitters. There is also a new class of drugs
called Serotonin-Norepinephrine Reuptake Inhibitors
(SNRI’s) that increase levels of both serotonin and
norepinephrine.
Because psychosis is one of the hallmark features of
schizophrenia, drugs used to treat the condition are
referred to as anti-psychotic medications. The
original, or typical, antipsychotics (E.g. Haloperidol,
Chlorpromazine and Trifluoperazine) have been
available for more than fifty years; more recently,
newer, atypical antipsychotics, have been developed.
Clozapine, Olanzapine, Risperidone, Quetipaine and
Ziprasidone are some of the second generation or
most commonly referred to “atypical medications”.
Studies of schizophrenia have focused on the
neurotransmitter, dopamine. The “dopamine theory of
schizophrenia” states that the behavioural patterns
typical of schizophrenia are a result of over-activity of
dopamine in certain regions of the brain. Serotonin is
also important in schizophrenia and it may interact
with dopamine to modify the way in which it operates.
All antipsychotic drugs tend to block D2 receptors in
the dopamine pathways of the brain. This means that
dopamine released in these pathways has less effect.
Excess release of dopamine in the mesolimbic
pathway has been linked to psychotic experiences. It
is the blockade of dopamine receptors in this
pathway that is thought to control psychotic
experiences.
First generation, or typical, antipsychotics seem to
act mainly by blocking D (Dopamine) 2 receptors,
whereas
second
generation,
or
atypical,
antipsychotics also block other dopamine receptors
such as D3 and D4, as well as receptors of other
neurotransmitters, including serotonin.
Bipolar Disorder
Bipolar disorder, also known as Manic Depression, is
a condition involving extreme changes in mood,
ranging from severe depression to intense mania.
Mania is elevated mood that can include increased
energy, rapid speech, irritability, over-reactions, poor
judgement, and decreased need for sleep.
It appears that brain chemistry plays a major role in
the development of bipolar disorder. Dysregulation in
the functions of various neurotransmitters are
believed to cause alterations in mood.
Mood stabilizers are medications used to regulate
fluctuations in mood. This class of medications
consists of lithium and certain anticonvulsant
medications, such as Epival, Lamotrigine and
Gabapentin. These medications are useful in both the
immediate treatment of current symptoms of an
episode and in preventing future episodes.
Mood stabilizers are believed to work by changing
the levels of neurotransmitters and the response of
the receptors that receive those transmitters in the
brain. For instance, lithium, a common treatment for
bipolar
disorder,
appears
to
affect
the
neurotransmitter dopamine by interfering with its
receptors while promoting the increase of serotonin.
Some recent studies have implied that mood
stabilizers might have neuroprotective effects (e.g.,
keep brain cells from dying when stressed).
The depressive phase is sometimes treated with
antidepressant medication, but care should be taken
because the use of antidepressants can trigger an
episode of mania.
NOTE: Because of their effects on anxiety, sleep,
and clarity of thinking, anti-psychotic medications are
frequently used, sometimes along with other
medications, to treat other disorders such as anxiety
and mood disorders.
In the News!
The risk of suicide with antidepressant
medication in youth: The U.S. Food and Drug
Administration (FDA) issued a “black box”
warning, the most serious type of warning a
medication can carry, on antidepressant
medications in 2004.
A similar warning was
issued by Health Canada. The warning alerted
users of an increased risk of suicidal thoughts
and actions among children, adolescents and,
more recently, adults through age 24, who take
the medications. Many doctors reported writing
fewer prescriptions for the medications after the
warning was issued. Disturbingly high suicide
rates in children and teens in the years since may
be the result. The report suggests a disturbing
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effects
of
genetic,
environmental,
and
experiential factors
that influence brain
development may provide targets for intervention
or prevention. The age of peak size in volume
varies by brain region but generally occurs during
late childhood or early adolescence. Particularly
late to mature is the prefrontal cortex — which is
involved in functions such as impulse control,
organization, judgment, and long term planning.
upward trend that correlates with a decline in the
use of antidepressants in young people. Many
psychiatrists now believe that the benefits of
using these medications, including relieving the
symptoms of depression that can lead to suicide,
outweigh their risks.
From: www.CTV.ca (04/07/08)
Emotion-Regulating Circuit Weakened in
Borderline Personality Disorder: Differences
in the working tissue of the brain, called grey
matter, have been linked to impaired functioning
of an emotion-regulating circuit in patients with
borderline personality disorder (BPD). People
with BPD had excess grey matter in a fear hub
deep in the brain, which over-activated when they
viewed scary faces. By contrast, the hub's
regulator near the front of the brain was deficient
in grey matter and underactive, effectively taking
the brakes off a runaway fear response, suggest
researchers supported in part by the National
Institute of Mental Health (NIMH). The imaging
studies are the first to link structural brain
differences with functional impairment in BPD
patients. Researchers used functional magnetic
resonance imaging (fMRI) to compare grey
matter in the BPD patients and healthy controls.
The results suggested an abnormality in the
number of neurons in these key components of
the emotion-regulating circuit, which other
evidence links to impaired functioning of the
serotonin chemical messenger system.
http://www.nimh.nih.gov/science-news/2008/emotionregulating-circuit-weakened-in-borderline-personalitydisorder.shtml
Role of brain development as risk factor for
mental illness: Increasing evidence points to
links between the timing and growth rates of
specific brain areas in the young brain and the
likelihood of developing a wide range of mental
disorders later in life.
"Most psychiatric
disorders, including those with adult onset such
as schizophrenia, are increasingly recognized as
being neurodevelopmental in origin," says
NIMH's Jay Giedd, MD. "A greater understanding
of the specifics of brain development, and where
the path of development goes awry in illnesses,
may be a key factor in devising better therapies."
The data consists of more than 6,000 magnetic
resonance imaging (MRI) scans from 2,000
subjects. Understanding the mechanisms and
http://www.nimh.nih.gov/science-news/2008/clues-torole-of-brain-development-as-risk-for-mentaldisorders-may-also-lead-to-better-treatments.shtml
The Tillmann Family Resource Centre offers a variety of
services for families and mental health professionals, including:
a Resource Library
which contains current books,
magazines, videos, audio tapes, and pamphlets on most
mental illnesses
an opportunity to meet one-on-one with another family
member who has had personal experience with mental
illness and the mental health system
participation in a support group comprised of 5-10 family
members affected by mental illness and facilitated by a
trained family member (every second Tuesday)
a FREE 7-week family education course offered twice per
year (Spring/Fall)
speakers for community groups
membership on the Family Advisory Council
a computer for family members to search for internet
information on mental illnesses
Located in Room A117 (down the left hallway off the main foyer of
RMHC – London), the resource centre is open:
Monday to Friday – 8:00 a.m. – 4:00 p.m.
Unless otherwise posted
*Donations to the resource center can be sent to:
SJHC Foundation
Attn: Dr. Wm. A. Tillmann Memorial Fund
Resource Centre for Families
268 Grosvenor Street
London ON N6A 4V2
We wish to thank Peter Toogood, Pharmacist at
Regional Mental Health Care, for his assistance in
proofreading and adding suggestions with this
issue of the Family Forum.
This newsletter is intended to be used as a communication vehicle
by the Family Advisory Council at Regional Mental Health Care
with families who share common interests and concerns. The
information herein is believed to be accurate; St. Joseph’s Health
Care London, the Family Advisory Council, and the author(s)
cannot be held responsible for any errors. It is the responsibility of
the reader to work with professionals when making any clinical
decisions.
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