Schizophrenia has a very wide range of clinical presentations, which can make the disease hard to define. What is common among all cases of schizophrenia is the fact that thought processes become disorganized and emotional responsiveness is gradually degraded. For a clearer definition, we can refer to DSM-IV's diagnostic criteria for schizophrenia, where we will find such criteria as disorganized speech, disorganized behaviour (e.g. emotional outbursts), and social/occupational dysfunction, which sheds light on the general clinical presentation of schizophrenia.
Let's take a look at the symptoms of the two main types of schizophrenia before we discuss causes.
There are two particular types of schizophrenia: positive and negative. Positive symptoms refers to the array of clinical presentations that are acquired as a result of the disease which otherwise would not appear in normal individuals. Negative symptoms refers to the lack of normal processes and behaviors which would otherwise be there in normal individuals.
Positive symptoms include delusions and hallucinations (which can be of an auditory, visual, tactile, olfactory or ...
The following discusses information on schizophrenia as well as its causes, symptoms, and treatments.