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What are psychotic disorders?

What are psychotic disorders?

When you look at the world around you, can you tell the difference between what is real and what isn’t? People who experience psychosis are out of touch with reality. They have trouble figuring out what parts of their life are real - they may see things that aren’t there or believe things that can’t possibly be true. Psychosis is a key feature of psychotic disorders, which are mental illnesses that cause changes in how a person perceives and interprets information. Three common psychotic disorders are schizophrenia, schizoaffective disorder, and schizotypal personality disorder.

How are things supposed to work normally?

Usually, your brain works constantly to gather and understand information about your body and its environment. To do this efficiently, your brain uses chemical messengers called neurotransmitters to help cells communicate with one another. Each neurotransmitter carries different messages throughout the brain and has important roles in controlling the body’s systems and functions. For example, normally glutamate manages the flow of information throughout the brain and keeps messages from becoming overwhelming, while dopamine tells different parts of the brain to turn on and off. When neurotransmitters work together properly, you are able to accurately perceive and interact with the world around you.

What happens when things go wrong?

Sometimes the communication system breaks down because there is too much or too little of a neurotransmitter in the brain (there is a chemical imbalance). When this happens, information isn’t processed correctly and the brain starts to make mistakes when it tries to interpret information or tell the rest of the body how to act. The effects of chemical imbalances can change based on the area of the brain that is affected and the neurotransmitters that are involved. Psychotic disorders are linked to abnormally high amounts of dopamine and low amounts of glutamate in many different parts of the brain, including areas that are involved in gathering and processing information about the world, controlling the body’s movement and emotions, thinking critically, and learning new things.
Occipital lobeseeing and understanding sight and visual information
Frontal lobesolving problems, planning, and organizing thoughts
Limbic systememotion
Auditory systemhearing and understanding speech
Basal gangliamovement, emotions, and integrating sensory information
Hippocampuslearning and memory


When a person loses touch with reality and experiences psychosis, there are several main symptoms they might have, which include:
  • beliefs that are abnormal, bizarre, or very clearly false
  • changes in perception, like sensing something that isn’t there
  • altered thinking patterns or speech patterns
  • decreases in motivation and emotional expression
  • changes in social relationships and behaviors
These symptoms vary from person to person – some experience brief periods of mild psychosis, while others have severe symptoms throughout their life and need to be hospitalized.
Schizophrenia: person experiences a severe break from reality that can continue for years. Symptoms of schizophrenia are usually mild at first but gradually become worse over time. For men, this process usually begins in the early to mid-twenties, and women start to develop symptoms in their late twenties. To be diagnosed, a person has to experience symptoms for at least 6 months, and must be psychotic for at least 1 month. More specific symptoms of schizophrenia include:
  • Delusions, or unusual beliefs about themselves or others that continue to be held despite exposure to the facts. Delusions can be about anything, but common ones are persecution (belief that they’re being harassed), grandeur (belief that they’re exceptional or have special talents) and thought control (belief that someone is influencing what thoughts are in their mind).
  • Hallucinations, or sensory perceptions that happen without any connection to a source or stimulus. Hallucinations can affect any of the five senses, but hearing voices or seeing things that aren’t there are most common.
  • Changes in thought and speech patterns, like:
  1. loose association, or trouble connecting ideas
  1. word salad, or linking random words together in a sentence
  • Negative symptoms that take away from normal functioning, like:
  • flat or blunted affect, or not being able express feelings
  • avolition, or not having energy or motivation to participate in life
  • anhedonia, or not being able to feel pleasure in life
  • asociality, or losing interest in making friends
Quick guide to diagnostic criteria: schizophrenia
Two or more of the following psychotic symptoms:Don't forget about
1. delusionsDuration: symptoms occur for 6 months or more, including one month of delusions, hallucinations, or disorganized speech
2. hallucinationsDistress: causes significant problems with work, social relationships, and personal life
3. disorganized speech
4. abnormal psychomotor behavior
5. negative symptoms
*at least one of these symptoms must be 1, 2, or 3
Schizoaffective disorder: person has an extreme break from reality and severe changes in mood at the same time. The disorder is like a cross between schizophrenia and a mood disorder, and symptoms of psychosis, depression, and mania can all overlap and mix together over time. To be diagnosed with schizoaffective disorder, a person has to experience symptoms for at least 1 month, and must have symptoms of schizophrenia without any symptoms of a mood disorder for at least 2 consecutive weeks during that month. More specific symptoms of schizoaffective disorder can include:
  • delusions
  • hallucinations
  • changes in thought and speech patterns
  • negative symptoms
  • moods that are abnormal and excessive
  • depression: feelings of extreme sadness
  • mania: feelings of extreme happiness and irritability
  • changes in body’s processes, like sleeping or eating
  • dysfunction in social relationships or behaviors
  • changes in overall activity level
  • thoughts of suicide
Quick guide to diagnostic criteria: schizoaffective disorder
Two or more of the following psychotic symptoms:Don't forget about
1. delusionsDuration: symptoms occur for at least one month, and psychotic symptoms occur for at least two weeks on their own
2. hallucinations
3. disorganized speech
4. abnormal psychomotor behavior
5. negative symptoms
*at least one of these symptoms must be 1, 2, or 3
Symptoms of a major mood episode (depressive or manic) at the same time

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