The term ‘Schizophrenia’ is derived from Greek words Schizein (to split) and phren (mind). Thus, the literal meaning of the word ‘schizophrenia’ is split mind. The term ‘schizophrenia’ was coined in 1911 by a Swiss psychologist, Paul Eugene Bleuler. Schizophrenia is a psychotic disorder. According to DSM-5 the two types of symptoms for schizophrenia are- 

(a) Positive symptoms are an excess addition to normal thoughts or behaviour of the period. Such symptoms are-

1. hallucinations – mainly auditory and visual hallucination 

2. delusions – mainly of grandeur, reference and persecution 

3. disorganized thought and speech 

4. bizarre body movements and disorganized behaviour 

5. incongruent affect.

(b) Negative symptoms are deficits of normal emotional responses or of thought processes. They lead to low level of functioning and may not improve much even with treatment. This includes

1. emotional blunting – diminished emotional expression 

2. anhedonia – inability to experience deep positive emotions 

3. alogia – diminished speed 

4. asociality – lack of desire to form relationships 

5. avolition – lack of motivation 6. apathy.

Sometimes, a schizophrenic exhibits positive as well as negative symptoms.