The abnormal psychologist studies extreme or unusual human behavior to explain its causes and find ways to change the behavior. Researchers in abnormal psychology or psychopathology, as it is also known, often study irregularities in behavior on both a statistical and qualitative basis. Abnormal psychologists describe mental abnormalities and categorize a wide range of disorders. Causes of abnormal behavior may be explained based on cognitive, behavioral or medical theories. Theories of abnormal psychology are used by clinicians to treat patients.
The abnormal psychologist often begins to define what is considered unhealthy behavior based on statistical analysis. He or she might use a bell curve to examine varying levels of deviation from what is considered normal. A bell curve is a statistical model that illustrates the distribution of data and can be used to study the range of behaviors within a population.
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Assessments about abnormal behavior are not only made on a statistical basis. Notions of what is normal behavior need to be viewed within the context of culture, sex, age and other demographic factors. The impact of the behavior is an important consideration in deciding whether it is normal or abnormal. For instance, behavior that causes harm to others or to the patient would definitely be considered irregular by the abnormal psychologist. Other harmful behaviors would include those that prevent the patient from functioning on a day-to-day basis.
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Mental disorders defined and studied by the abnormal psychologist are categorized. One category, anxiety disorders, includes illnesses such as panic disorder and post-traumatic stress syndrome. Alzheimer's disease and amnesia fall under the category of cognitive disorders. Attention deficit hyperactivity disorder (ADHD) and autism are considered to be developmental disorders.
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Major theories used by abnormal psychologist to describe psychopathology include cognitive, behavioral and medical. Cognitive theories focus on unhealthy thought patterns, and perceptions about the world and how they contribute to mental illness. Behavioral theories look at ways to discourage disruptive behaviors and replace them with more positive ones. Chemical imbalances, genetic influence and other biological conditions are components of medical theories of abnormal psychology.
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Psychologists who treat patients in clinical settings, such as private practices, mental health facilities and hospitals rely on theories of abnormal psychology to understand and describe patient disorders. The American Psychiatric Association publishes the Diagnostic and Statistical Manual of Mental Disorders, which provides information used by clinical psychologists. Among other facts, the manual contains statistical information on gender distribution and effective treatments for abnormal behavior.