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Diagnostic Criteria
What is schizophrenia?

What are the related disorders?

What do the symptoms mean?

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Diagnostic Criteria

Schizophrenia and Related Disorders

By Tamara J. Navarro, PhD, Consumer

(Note: Mouse Click on the category to expand the section)

  • Introduction
    • Psychiatrists and other mental health workers, who provide services to people who suffer from mental illnesses, rely on a book published by the American Psychiatric Association titled Diagnostic and Statistical Manual of Mental Disorders (Shortened to DSM). This book has been written in different ways four times. The current book used is DSM-IV. DSM-IV is different from books that list known physical illnesses. These books diagnose the illness based on what caused a person feel bad (symptoms).
      Doctors know that measles is caused by a virus and that a person with measles gets a rash special to measles. Doctors know that diabetes is due to an organ, called the pancreas that does not let the body use sugar in the right way. The DSM-IV is not about what causes a mental illness because doctors are not sure what causes mental illness. But in order for psychiatrists and other mental health workers interested in mental illnesses, to talk with each other in a shorter way, the DSM-IV was written. So the DSM-IV puts together symptoms, like hearing voices and seeing things no one else sees, and others symptoms that many people share and give it a name (A Diagnosis). This is very hard to do and some mistakes happen, but it also helps doctors and people (researchers) who study mental illnesses to find out what causes different mental illnesses. This paper is designed to answer in understandable words: What is schizophrenia, and what are the related disorders, and what do they mean?
      The DSM-IV is a very large book and includes many mental disorders. This paper will only focus on schizophrenia and related disorders.
  • Definitions
    • The word "psychosis" is a defining feature in schizophrenia and all the related disorders. The most accepted meaning of the word "psychosis" refers to symptoms, described below, such as delusions, hallucinations, disorganized speech, grossly disorganized thinking or behavior, or catatonic behavior. These symptoms are called positive symptoms. Along with positive symptoms, psychoses also have negative symptoms which include affective flattening, alogia or poverty of speech and avolition. So what do these symptoms mean?

      1.      Delusions: Delusions cover a wide area of types. Delusions are usually beliefs a person has which have no real evidence that most people would believe, depending on the person's culture. Persecutory delusions are most common; the person believes he or she is being tormented, followed, tricked, spied on or feels ridiculed (teased, laughed at). Referential delusions are also common; the person believes that certain gestures, comments, passages from books, newspapers, or song lyrics are meant just for him or her. Bizarre delusions are most common for people who have schizophrenia but may be hard to judge across different cultures; a person believes that a stranger has removed his or her internal organs and has replaced them with someone else's organs without leaving any wounds or scars, or a person believes that his or hers thoughts have been removed from his or her head. A person may believe he or she is President of the United States or that he or she is capable of flying.

      2.      Hallucinations: Hallucinations are distortions of the senses, auditory - hearing voices or sounds no one else hears; visual - seeing people who no one else can see or animals no one else can see or even artistic patterns like paintings no one else sees; olfactory - smelling bad odors no one else smells; gustatory - tasting things that have not been put in his or her mouth or tasting things differently from other people; and tactile - feeling spiders are all over his or her skin or feeling numbness in the hands or feet.

      3.      Disorganized speech: Derailment or loose associations (the person may slip off from one subject to another unrelated subject); tangentiality (the person may answer a questions completely unrelated to the question); and incoherent speech (sometimes called "word salad," the person's speech appears to be just a bunch of words that have no real meaning).

      4.      Grossly disorganized thinking and behavior: Childlike silliness to unpredictable agitation (laughing for no known reason or feeling very nervous also for no known reason). This person may find it difficult to perform activities of daily living such as fixing meals or the person may have problems taking showers when needed or wearing multiple overcoats, scarves and gloves on a hot day.

      5.      Catatonic: This person may stand like a statue for a long time or this person may not get out of the way when a car is coming toward them. This person may dance when there is no music.

      6.      Affective flattening: The person's face doesn't seem to move (show happiness or sadness). This person may not look at people in the eyes and their body may not change to show feelings.

      7.      Alogia: This person may not speak or may give brief and empty replies to people who are talking to them. A related symptom is a poverty of speech. This person may say just a few words or may not talk at all.

      8.      Avolition: This person seems to not want to do anything or they may not finish tasks. This person may stay in bed all day.

  • Diagnostic Criteria for Schizophrenia
    • Symptoms: Two (or more) of the following, each present for a significant portion of time during a one-month period (or less if successfully treated).

      1.      Delusions

      2.      Hallucinations

      3.      Disorganized speech (e.g., frequent derailment or incoherence)

      4.      Grossly disorganized or catatonic behavior

      5.      Negative symptoms, i.e., affective flattening, alogia or avolition

      Note: Only one Criterion A symptom is required if delusions are bizarre or hallucinations consist of a voice that keeps talking about everything the person is doing or two or more voices talking with each other.

  • Subtypes of Schizophrenia
    • Psychiatric professionals have divided schizophrenia into different types usually based on the most noticeable symptoms or lack of a noticeable symptom. There are five types currently agreed upon. These are: Paranoid Type, Disorganized Type, Catatonic Type, Undifferentiated Type and Residual Type.

      1.      Paranoid Type: There are two main symptoms in this type. One of these is delusions which tend to be about jealousy, or religious in nature. The person with this type may display anger and see himself or herself as superior to others. The other symptom is auditory hallucinations which are related to the delusion story. The psychiatric professionals usually agree that a person with this subtype usually has the best recovery because there is little, if any, impairment in cognitive functioning. This means they maintain knowledge and awareness of the real world, and often they stay at their jobs and can live independently.

      2.      Disorganized Type: The main symptoms of this type of schizophrenia is disorganized speech, disorganized behavior and flat or inappropriate affect (See definition 6). A person with this type may act silly or laugh apparently for no reason.

      3.      Catatonic Type: One of the main symptoms of this type relates to how the person moves. This person may move too much or not move at all. This person may have a symptom called echopraxia which is the imitation of the movements of another person. This person may have another symptom called echolalia. Echolalia is parrot like speech. This person might repeat a word or phrase just spoken by another person.

      4.      Undifferentiated Type: A person with this type of schizophrenia meets the criterion listed above for Schizophrenia, but this person does not display the symptoms of any of the other types.

      5.      Residual Type: A person with this type would have had, at least at one time, when they showed positive symptoms (delusions, hallucinations, disorganized speech or behavior) but the positive symptoms stop. However, this person would have some of the negative symptoms still present (flat affect, poverty of speech or avolition).

  • Related Disorders
    • In related disorders a person has symptoms of a disorder other than schizophrenia but has some psychotic symptoms as well. These disorders are usually known as mood disorders. There are two major mood disorders which can have added psychotic symptoms and one disorder where a person would have the symptoms of schizophrenia but also have symptoms related to a mood disorder.

      What are mood disorders? Mood generally means how a person feels (happy, sad, angry, etc.). There are two major mood disorders included in DSM-IV: Major Depression, recurrent and Bi-Polar Disorders.


      1.      Depression: Feeling very sad or empty

      2.      Markedly diminished: Very little

      3.      Significant: A lot

      4.      Insomnia: Lack of sleep

      5.      Hypersomnia: Sleeping most of the time

      6.      Psychomotor agitation: Nervousness or moving around a lot

      7.      Manic: Abnormally long period of time feeling high (without having taking any drug) or, expansive (This person feels that he can do anything) or irritable (angry) mood.

      8.      Grandiosity: Feeling smarter, stronger and prettier than anyone else or feeling they control everything.

      9.      Flight of ideas: Having ideas race through a person's mind, too fast and out of control.

  • Diagnostic Criteria for Major Depression, Recurrent
    • Symptoms: Five or more of the following symptoms that have been present for at least two weeks:

      1.      Depressed mood (feeling sad or empty) most of the day, nearly every day

      2.      Poor concentration or difficulty making decisions

      3.      Significant weight loss when not dieting, or weight gain

      4.      Insomnia or sleeping a lot of the time nearly every day

      5.      Feelings of hopelessness or worthlessness

      6.      Fatigue or loss of energy nearly everyday

      7.      Feelings of wanting to die

      Sometimes a person with this mental illness may also have psychotic symptoms, like delusions or hallucinations. Then the diagnosis will say "with psychotic features."

  • Diagnostic Criteria for Bi-Polar Disorders
    • There are many different types of Bi-Polar Disorders. This paper will just present the common symptoms of Bi-Polar Disorders. In general, a person who has a Bi-Polar Disorder goes back and forth from having symptoms of depression and symptoms of mania. Sometimes people with a Bi-Polar disorder only have manic symptoms. Depression symptoms have already been addressed previously, but manic symptoms have not been addressed yet.

      Manic Symptoms

      1.      No need to sleep

      2.      Feeling forced to talk

      3.      Racing thoughts

      4.      Elevated mood (feeling very high)

      5.      Expansive mood (feeling larger than life, feelings that one can do any things)

      6.      Distractibility (can't pay attention to just one thing)

      7.      Excessive involvement in pleasurable activities which often have bad outcomes (Buying things a person can't pay for, or doing dangerous things that a person is not trained to do, like jumping out of an airplane or driving too fast in a car, or having sex very often with many different people).

      A person who has a Bi-polar disorder can also have psychotic symptoms most of the time they are delusions. This person may believe they have a special relationship with a movie star or the president or a famous athlete. Sometimes this person may experience hallucinations. If psychotic symptoms are present then the diagnosis will say "with psychotic features." 

  • Diagnostic Criteria for Schizoaffective Disorder
    • A person with schizoaffective disorder has the symptoms of schizophrenia, but at the same time there would be symptoms of depression, mania or mixed depression and mania. 

  • Conclusion
    • Remember the DSM-IV doesn't explain the cause of a mental illness but just puts together different combinations of symptoms that many people have in common and then gives them a name. The reason for doing this is to make it easier to talk about mental illnesses and to treat the symptoms of a mental illness. This also makes it easier for scientists to learn more about a mental illness to try to find out what causes mental illnesses and some day cure them.

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