Classification and diagnosis of schizophrenia:

Schizophrenia means split mind because there is a loss of contact with reality, disturbances of thought process and disturbances of emotion/behaviour. There are two types of symptoms: positive and negative. Positive symptoms is an excess distortion of a normal function (exaggeration) and a negative symptom is a loss of normal function. The two major classificatory systems for psychological disorders are DSM-IV (American psychiatric association) and ICD-10 (world health organisation).

The diagnostic criteria from the DSM-IV:

• Control of thoughts. (+)

• Delusions of control. (+)

• Hallucinatory voices. (+)

• Other persistent delusions and hallucinations. (+)

• Breaks in train of thought. (-)

• Catatonic behaviour. (-)

• Change in personal behaviour (-)

The possibility of a mood disorder or organic causes (e.g. drug abuse or a brain tumour) must be excluded.

Both classifications identify a number of subtypes of schizophrenia. The DSM-IV lists five subtypes:

1. Paranoid schizophrenia: the main features are delusions, particularly delusions of prosecution and hallucinations. They are usually agitated, angry, argumentative and highly suspicious of others.

2. Disorganised schizophrenia: once called hebephrenic schizophrenia (silly mind). Symptoms include giggling, pulling faces and flat or inappropriate affect. Disorganised speech is common as is disorganised behaviour such as not washing or brushing teeth.

3. Catatonic schizophrenia: some people in this category spend long periods immobile, in catatonic stupors. Others exhibit catatonic excitement with wild, uncontrollable motor movements.

4. Undifferentiated schizophrenia: people who don’t fit into any of the sub categories.

5. Residual schizophrenia: the symptoms are reduced in number and intensity but signs of the disorder are still present....