Schizophrenia
...ort-term and working memory, and processing speed. However, they are no worse than the general population in underlying (implicit) learning, such as grammar skills, vocabulary, and spatial skills (e.g., map reading). Some experts believe that impaired verbal memory in schizophrenia is a consequence of depression and slowness, but not a result of the disease process. Researchers haven't identified the cause or causes of schizophrenia, although they believe genetic factors play a role. Chemical or subtle structural abnormalities in the brain may contribute to causing this illness. Many studies have reported an association between schizophrenia and problems surrounding birth, particularly those that cause oxygen deprivation, which could effect the nerve systems in the developing brain. Specific complications that have been associated with such a higher risk include the following; Prolonged labor. Bleeding during pregnancy. A short gestation PAGE 5 period and low birth weight. Schizophrenia may exist alone or in combination with other psychiatric or medical conditions. Misconceptions about schizophrenia and its relation to other mental illnesses abound. The following truths will help clarify what it is and is not; Schizophrenia isn't the same as a split or multiple personality. Multiple personality disorder is a separate, rare condition. Although some people with schizophrenia develop violent tendencies, most don't. Many withdraw into themselves rather than interact with others. Not everyone who acts paranoid or distrustful has schizophrenia. Some people have a paranoid personality disorder, a tendency to be suspicious or distrustful of others, without the other features of schizophrenia. Not everyone who hears voices is schizophrenic. Some people with depression may hear voices. Hearing voices may also occur as a result of a serious medical illness or from the effects of medication. By its nature, schizophrenia often isn't an illness for which someone is likely to voluntarily seek treatment. To a person with schizophrenia, the delusions and hallucinations are real, and often he or she may perceive that there's no need for medical help. If you're a family member or friend of someone who is exhibiting possible signs of schizophrenia or another mental disorder, someone close to them may need to be the one who takes him or her to a medical professional for evaluation. PAGE 6 Abnormalities of Brain Volume and Activity. Imaging techniques have revealed reduced volume and actual loss of tissue in the brains of people with schizophrenia. Of particular importance are volume losses and abnormal activity in the prefrontal cortex and the temporal lobes . Reductions in volume of the prefrontal cortex have been observed in many patients with schizophrenia. This area affects verbal memory, attention, reasoning, aggression, and meaningful speech. (Not all patients have the same deficits. For example, one study reported that patients with paranoid schizophrenia tend to have preserved left prefrontal volumes.) Over activity in the specific parts of the frontal and the right temporal lobes has been associated with auditory hallucinations (e.g., hearing voices). Loss of volume in the temporal lobe affects the limbic areas (located deep in the brain), which contain the hypothalamus, amygdala, and hippocampus. Activity in this area is related to emotions and memory, and abnormalities are associated with positive symptoms, including delusions and hallucinations, and also with disordered thinking. Some evidence suggests that abnormalities here occur after the disease process has started or may only indicate a susceptibility to the disease. Abnormal Brain Chemicals. Schizophrenia is associated with an unusual imbalance of neurotransmitters (chemical messengers between nerve cells) and other factors. PAGE 7 Abnormalities in dopamine receptors. Imbalances in the neurotransmitter dopamine are important research targets in schizophrenia. Dopamine over activity is now known to be closely linked to reduced prefrontal cortex activity. Over-activity, particularly the left side, is associated with psychotic symptoms and appears to be due to an increase in specific chemical receptors, particularly those called C1 and D1. (These receptors attract and lock dopamine.) Abnormalities in glutamate receptors. Glutamate, an amino acid known to affect dopamine and excite nerve activity, is also under scrutiny. For example, glutamate binds to N-methyl-D-aspartate (NMDA) receptors, which play a critical role in healthy nerve development and may be abnormal in schizophrenia. Abnormalities in NMDA and other molecules in the glutamate pathway appear to play significant roles in impairment of mental function and development of negative symptoms. Abnormal Circuitry. Abnormalities in brain structure are also reflected in the disrupted connections between nerve cells that are observed in schizophrenia. Such miswiring could impair information processing and coordination of mental functions. For example, auditory hallucinations may be due to miswiring in the circuits that govern speech processing. Strong evidence suggests that schizophrenia involves decreased communication between the left and right sides of the brain. PAGE 8 Loss of reelin. A protein called reelin, which is involved in the nerve cell architecture, is also being investigated. Studies have observed abnormally lower levels of reelin in the prefrontal cortex region of patients with both schizophrenia and bipolar psychosis, perhaps contributing to psychosis and to impaired information processing. Non-Right Handedness. The prevalence of mixed- and left-handedness is significantly higher in patients with schizophrenia than in the general population, suggesting some neurological pattern that may be responsible for each. (A large minority of the population is non-right handed and very few of these people develop schizophrenia.) Abnormal Olfactory Bulbs. Studies are reporting impairment in the sense of smell in patients with schizophrenia. One study reported abnormally small olfactory bulbs in patients with schizophrenia. Olfactory bulbs are nerve centers in the brain that regulate the sense of smell. Obsessive-Compulsive Disorder. Obsessive compulsive disorder (OCD) affects a significant number of schizophrenic patients. OCD is an anxiety disorder marked by obsessions (recurrent or persistent mental images, thoughts, or ideas) that may result in compulsive behaviors, repetitive, rigid, and self-prescribed routines that are intended to prevent the manifestation of the obsession. Some experts believe the behaviors exhibited in the disorder may PAGE 9 actually be protective in people with schizophrenia in early stages. Behavioral and Motor Problems in Childhood. Children who later develop schizophrenia often suffer from the following certain problems, including excessive shyness or minor early physical and motor-control problems. Such problems are so common, however, that their presence without any other risk factors is no cause for concern. Malnutrition in the Pregnant Mother. Malnutrition in the mother during the first trimester of pregnancy (less than 1,000 calories a day) has been associated with later schizophrenia in the child. Nutritional deficiencies during that time are believed to impair fetal brain growth. Father's Age. According to one 2001 study, the older a father is when a child is born, the greater the child's risk is for schizophrenia, perhaps because of a greater chance of genetic mutations in the sperm that can be passed on. In the study, children whose fathers were 50 years old or more or faced a three-fold risk for schizophrenia compared to children whose fathers were 25 or younger. Early diagnosis and treatment of schizophrenia are important. Before making a diagnosis of schizophrenia, a doctor likely will rule out other possible causes of the signs that may suggest schizophrenia. It's possible that other mental or physical illnesses may cause signs similar to schizophrenia. Research is ongoing to find simple tests that will detect schizophrenia accurately and early enough to initiate preventive measures. Some examples PAGE 10 include the following; One investigative test uses computers to analyze brain scans and identify changes in blood flow indicative of schizophrenia, even before symptoms occur. It appears to be highly reliable, and more research is warranted. A blood test that detects genetic evidence of high levels of D3 dopamine receptor may prove to useful. People with schizophrenia have over three times the normal amount of this substance. Measurements of certain esters (phosphomonoesters and phosphodiesters) may detect high-risk individuals. A doctor will want to discuss your family and medical history and do a physical examination. The doctor may ask for blood or urine samples to see if medications, substance abuse or another physical illness may be a factor in those signs. Among the other mental illnesses that may at least partly resemble schizophrenia are depression, bipolar disorder, other psychoses, and abuse of alcohol and other drugs. It's also possible that physical illnesses such as certain infections, cancers, nervous system disorders, thyroid disorders, immune system disorders and others may produce some psychotic signs. Psychosis is also a possible side effect of some medications. If no other underlying cause is found, doctors diagnose schizophrenia based on the signs and symptoms summarized above. Antipsychotic medications, also known as neuroleptics, are the cornerstone of treatment. Until the 1990s, antipsychotics generally were much PAGE 11 more effective in controlling positive symptoms than negative symptoms. A new generation of antipsychotics provides more effective management of both positive and negative symptoms. Th...