Schizophrenia is a psychotic disorder and is attributed to an individual if they have two or more core symptoms; delusions, hallucinations, disorganized thinking and/or speech. The other core symptoms are significantly disorganized or abnormal motor behaviour, and negative symptoms. Delusions are fixed beliefs that are resistant to change despite conflicting evidence. For example, this might be a strong belief that someone is going to be harmed by another individual, despite there being no evidence of that being true. This is defined as a specific delusion called a persecutory delusion, which is the most common. Hallucinations are experiences that occur without an external stimulus (outside reason or cause). They are vivid and clear, like a voice speaking to you which is not just one’s individual inner thoughts; this is called an auditory hallucination. Disorganized thinking and speech can be quite sporadic in nature, whether a person jumps from idea to idea, or their ideas are completely unrelated, or their words or sentences just do not make sense. Disorganized or abnormal motor behaviour can be observed as a childlike “silliness” to unpredictable agitation. It can be seen as odd posture, excessive motor activity, staring, and more. Negative symptoms are diminished emotional expression seen in one’s face, eye contact, or delivery of speech and avolition which is a decrease in motivated self-driven activities such as sitting for long periods of time without interest in participating in work, school, or social activities
Prevalence:
- The psychotic features of schizophrenia typically emerge between the late teens and mid-30s; onset prior to adolescence is rare
- The peak age at onset for the first psychotic episode is in the early- to mid-20s for males, and late-20s for females
- Schizophrenia affects less than 1% of the population, meaning it is fairly uncommon and is highly genetically related
- There is a high suicide risk among those with schizophrenia as it can be a response to a command hallucination to harm oneself or others and must be taken seriously
- In general, schizophrenia tends to be slightly lower in females than males