Signs and symptoms

Schizophrenia is a severe psychiatric illness characterized by:

  • positive symptoms
  • negative symptoms
  • cognitive problems 




Positive symptoms

Positive symptoms refer to hallucinations and delusions.

Hallucinations are experiences in any one of the five senses that are not linked to something happening in the person’s environment.

Delusions are beliefs that are not true. For example, someone may believe that other people are sending messages to them telepathically.



Negative symptoms

Negative symptoms, the second major group of schizophrenia symptoms, refer to a range of behaviours such as:

  • showing little emotion
  • having problems with motivation
  • slowed movements
  • withdrawing from others.



Cognitive problems

This manual focuses on cognitive problems. 

People with this illness often have trouble focusing their attention on an activity when distracting things are going on around them.


  • People may have trouble filling out a form while people are talking nearby.
  • They may also have difficulty staying focused, sometimes for as little as a few minutes.
  • Memory difficulties are also common.
  • Remembering everything from verbal and written instructions to completing routine day-to-day tasks can present a tremendous challenge for people with the illness.
  • Finally, people with schizophrenia often have problems in what we call “executive” functions.