Duhaime's Law Dictionary

Schizophrenia Definition:

A severe, chronic and generally disabling mental disorder that severely disrupts normal thoughts, speech and behavior.

Related Terms: Mental Disorder, Anti-psychotic Drugs

The DSM-IV of the American Psychiatric Association defines schizophrenia as a clinical mental disorder:

"This large category includes a group of disorders manifested by characteristic disturbances of thinking, mood and behavior. Disturbances in thinking are marked by alterations of concept formation which may lead to mis-interpretation of reality and sometimes to delusions and hallucinations, which frequently appear psychologically self-protective. Corollary mood changes include ambivalent, constricted and inappropriate emotional responsiveness and loss of empathy with others. Behavior may be withdrawn, regressive and bizarre. The schizophrenics, in which the mental status is attributable primarily to a thought disorder, are to be distinguished from the major affective disorders which are dominated by a mood disorder. The paranoid states are distinguished from schizophrenia by the narrowness of their distortions of reality and by the absence of other psychotic symptoms."1

The 17th edition of the Merck Manual defines schizophrenia as follows:

"A common and serious mental disorder characterized by looss of contact with reality, elusions, abnormal thinking, flattened effect, diminished motivation and disturbed work and social functioning."

Symptoms include unrealistic thinking, severe anxiety, excessive suspiciousness, perplexity or confusion, social withdrawal, auditory hallucinations, overactivity, a feeling of impending doom and generalized motor inhibition.

In Basi, the  Justice Macaulay wrote:

"Schizophrenia is a serious, incurable, lifelong psychotic mental disorder that starts developing years before the symptoms become florid.  By its nature, a period of psychosis typically occurs before diagnosis."

mazeIn Mercurio v. Rizza, Justice Damrot of the Ontario Supreme Court accepted this expert2 opinion:

"(The expert) describes schizophrenia as a neurobiological disorder, frequently associated with physical findings such as enlargement of the ventricles, widening of sulci and decreased grey matter in the brain. She describes the cause of schizophrenia as heterogeneous, or dependent on more than one factor. Minor head injury is one of the risk factors which may play a role in the development of schizophrenia. The first episode of schizophrenia often occurs during or following a time of psychological or physical stress.

"Other evidence placed before me establishes that schizophrenia is a psychiatric disorder of multiple causation, not all elements of which are fully understood. There are a number of genetic, environmental and psychological risk factors which can predispose an individual to the disease. The use of street drugs can be a precipitant to schizophrenia. Despite a tremendous amount of research, the world literature has yet to establish a definite organic cause for schizophrenia which, in the vast majority of cases, is not associated with any brain injury at all. The literature has not supported a cause and effect relationship of head trauma to the development of schizophrenia, although there have been sporadic reports, as in this case, of an association.

[The expert] also stated that life stressors are considered to be an important factor in the development of schizophrenia. The first episode of schizophrenia often occurs during or following a time of physical stress, and subsequent exacerbations or relapses of the illness are also frequently associated with stressful life events."

The average age of diagnosis for schizophrenia is 21 years of age for males and 24 to 25 years of age for females. Genetics is the contributing factor in eighty percent of cases of schizophrenia.

The National Instituite of Mental Health writes, in 2010:

"[Schizophrenics] ... may hear voices other people don't hear. They may believe other people are reading their minds, controlling their thoughts, or plotting to harm them. This can terrify people with the illness and make them withdrawn or extremely agitated.

"People with schizophrenia may not make sense when they talk. They may sit for hours without moving or talking. Sometimes people with schizophrenia seem perfectly fine until they talk about what they are really thinking.

"Many people with schizophrenia have difficulty holding a job or caring for themselves, so they rely on others for help.

"Treatment helps relieve many symptoms of schizophrenia, but most people who have the disorder cope with symptoms throughout their lives."


  • Basi v Basi, 2007 BCSC 1814
  • Beers, M. and others, editors, The Merck Manual of Diagnosis and Therapy, 17th Ed. (Whitehouse Station, New Jersey: Merck Research Laboratories, 1999).
  • Duhaime, Lloyd, Duhaime's Legal Dictionary
  • Mercurio v Rizza, 39 O.R. (3d) 728 (1998)
  • As quoted in In re Jamie M., 134 Cal. App. 3d 530 (1982)
  • Note 2: quoting psychiatrist Dr. Eva W.C. Chow, Clarke Institute of Psychiatry, Toronto, Ontario, Canada. Dr. Chow is a lawyer and psychiatrist.


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