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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. 1 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 2 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 3 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. 4 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, 5 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 6 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. 7