Schizophrenia is a form of psychosis, in which the clear distinction between one’s inner world of thoughts and emotions and perceptions about the outside world weakens or ceases to exist. This can lead to abnormal thoughts, beliefs and behaviours. One may, for example, hear a thought as a voice from the outside or have the sense that an outside event or another person has an influence on one’s inner world of thoughts and emotions. The former can lead to hallucinations and the latter to paranoid delusions.
Typically, schizophrenia begins in early adulthood. Untreated it has an unfavourable prognosis and can lead to social withdrawal, suicidality and prolonged hospitalisations. Schizophrenia probably involves abnormal dopamine levels in certain areas of the brain, which is where antipsychotic medication is believed to help reduce the symptoms.
Symptoms that have to be present for at least 30 days are hallucinations, delusions, disorganised speech, disorganised or catatonic behaviour and negative symptoms. Negative symptoms can be emotional flatness, apathy or a lack of speech. Emotional flatness refers to a lack in emotional responsiveness, which is common in psychosis, but also other mental disorders, such as depression. Difficulties in working and long-term memory, attention, executive functioning, and speed of processing also commonly occur. Often there is also social withdrawal, deficits in personal hygiene, focus on bizarre belief systems, lack of motivation, and strange behaviours.
The hallucinations are most often acoustic in the form of hearing voices. Delusions and beliefs are often paranoid. Depersonalisation, the feeling that oneself is different, and derealisation, the feeling that the world around is different, often occur. The sense that thoughts which are not one’s own are being injected or can be received and understood (“thought transfer”) also occur.