Classification of schizophrenia

Specification: Classification of schizophrenia. Positive symptoms of schizophrenia, including hallucinations and delusions. Negative symptoms of schizophrenia, including speech poverty and avolition. 

What is Schizophrenia?

Schizophrenia is a mental illness that usually occurs in late adolescence or early adulthood, but it can occur at any time in life. 

In the Diagnostic and Statistical Manual (DSM) it is classified as a psychosis, as the sufferer has no concept of reality. Essentially the illness is due to a breakdown of the patient’s personality.

Schizophrenia is a worldwide disease i.e. culturally universal; however, both the symptoms and the incidence (how common it is) vary from culture to culture. Approximately 1% of the population develops schizophrenia during their lifetime, which is an enormous number. More than 2 million Americans suffer from the illness in a given year.

The peak of incidence for onset is 25-30 years and cases prior to adolescence are extremely rare. Overall there are no gender differences: a similar number of men and women are diagnosed with the disorder. However, the disorder often appears earlier in men than women (Warner 1994). Twice as many men as women between the ages of 15 and 24 years are diagnosed, but between 25 to 34 years the incidence of females rises, until after 35 years of age, the two sexes are similar in the rate of incidence.

Available treatments can relieve many symptoms, but most people with schizophrenia continue to suffer some symptoms throughout their lives; it has been estimated that no more than one in five individuals recovers completely.

Although recovery from schizophrenia is rare (1% of the population suffer from it), recent research has given hope to sufferers and their family members. Research has identified new, safer medications and has started to unravel the complex causes of the disease. New insights into the disorder have come from several areas of Psychology such as molecular genetics, the study of populations, brain imaging (e.g. MRI Scans) and brain function studies. 


Positive Symptoms

Schizophrenia can cause ‘positive symptoms’, which are symptoms that are not usually present in a normal person. Positive symptoms reflect an excess or distortion of normal functioning. People with schizophrenia often suffer terrifying symptoms such as hearing internal voices not heard by others, or believing other people are reading their minds or plotting to harm them. These symptoms may leave them fearful and withdrawn. Their speech and behaviour can be so disorganised that they may be incomprehensible or frightening to others.

Delusions are false beliefs that are firmly held despite being completely illogical, or for which there is no evidence. Common types of delusions in schizophrenia include the following:

Hallucinations involve disturbances in perception. They are perceptions that have no basis in reality. The most common hallucination is auditory (hearing voices) but can include smell, touch and sight. There may appear to be a single person talking or many, and they may be familiar or unfamiliar. Many schizophrenics report hearing voices that instruct them to do something, or that tell them they are wicked and evil. Sometimes they instruct the patient to do something that could be harmful to themselves and others.


Negative Symptoms

Schizophrenia can cause ‘negative symptoms’ which cause a decline in functioning. Negative symptoms appear to reflect a loss of normal function. For example, sufferers may not be able to work at a job that requires the same level of skill or concentration as the job they held before they became ill, or they may lose all ability to withstand the stress of working. The illness can also affect their ability to function at home; for instance, they may be unable to complete household chores, raise their children or maintain an active social life.

Speech poverty is the inability to speak properly, characterised by a lack of ability to produce fluent words; this is thought to reflect slowing or blocked thoughts. It can manifest itself as short and empty replies to questions.

Avolition is the reduction, difficulty, or inability to start and continue with goal-directed behaviour. It is often mistaken for apparent disinterest. Examples of avolition include: no longer being interested in going out and meeting with friends, no longer being interested in activities that the person used to show enthusiasm for, no longer being interested in anything, sitting in the house for many hours a day doing nothing.

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