Schizophrenia is a serious mental illness characterized by a broad range of unusual behaviors that cause profound disruption in the lives of the patients suffering from the condition — and often in the lives of the people around them, too. Schizophrenia strikes without regard to gender, race, social class or culture. It is most often first diagnosed in a person’s 20s: early- to mid-20s for men, later 20s for women.

Not everyone who has schizophrenia experiences every symptom. Some people experience a few symptoms, some many. The severity of symptoms varies with individuals and also varies over time. Just over 1 percent of the American population can be diagnosed with schizophrenia over the course of a year, and most people — over 60 percent — normally seek treatment for this condition. Treatment typically involves psychiatric medications combined with psychotherapy.

The top 10 signs of schizophrenia are:

  1. Delusions (believing things that are not true)
  2. Hallucinations (seeing or hearing things that are not there)
  3. Disorganized thinking (can’t keep thoughts ordered)
  4. Disorganized speech (e.g., frequent derailment of the conversation, loose associations, or talking incoherently)
  5. Agitation
  6. Grossly disorganized or catatonic behavior (e.g., childlike “silliness,” resisting simple instructions, odd or rigid posture, repeated movements that serve no purpose)
  7. Lack of drive or initiative
  8. Social withdrawal
  9. Apathy
  10. Emotional unresponsiveness or lack of emotional expression

Learn more: Complete Symptoms of Schizophrenia

Explore: Schizophrenia Education Guide

One of the most important kinds of impairment caused by schizophrenia involves the person’s thinking. Because of the hallucinations and delusions they are experiencing, the individual can lose much of the ability to rationally evaluate their surroundings and interactions with others. These hallucinations and delusions reflect distortions in the perception and interpretation of reality and the world around them.

The resulting behaviors may seem bizarre to the casual observer, even though they may be consistent with the person suffering from schizophrenia’s internal perceptions and beliefs.

It is rarely helpful to challenge a person who has schizophrenia’s beliefs or hallucinations directly, since they may make a kind of sense to the person. Instead, a person should be seen professionally for treatment of this condition. Modern treatment for schizophrenia includes both medications and psychotherapy.

Individuals with schizophrenia may also have:

  • Inappropriate displays of emotion (e.g., laughing for no reason)
  • Depression, anxiety or anger
  • Daytime sleeping, or disturbed sleep
  • Lack of interest in eating or food
  • Anxiety or a phobia
  • Problems with memory
  • Lack of insight or awareness of the schizophrenia symptoms

Learn more: Schizophrenia symptoms, treatments, and more