Schizophrenia is a chronic, severe, and disabling mental disorder characterized by deficits in thought processes, perceptions, and emotional responsiveness.
Schizophrenia’s symptoms are typically described as “positive” or “negative.” Positive symptoms are those that are found among people with schizophrenia but not present among those who do not have the disorder. These may include delusions, thought disorders, and hallucinations. People with schizophrenia may hear voices other people don't hear, or believe other people are reading their minds, controlling their thoughts, or plotting to harm them. Negative symptoms are those found among people who do not have the disorder but that are missing or lacking among individuals with schizophrenia. These may include avolition (a lack of desire or motivation to accomplish goals), lack of desire to form social relationships, and blunted affect and emotion. These symptoms make holding a job, forming relationships, and other day-to-day functions especially difficult for people with schizophrenia.
Schizophrenia is an incredibly complex disorder that has increasingly been recognized as a collection of different disorders. It has also increasingly been viewed from a developmental perspective, with full psychosis representing a late stage of the disorder, fueling the hope that early, intense interventions may provide greater help to people in the long term.
Additional information on schizophrenia can be found on NIMH's schizophrenia page.
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