What are psychotic disorders and who's at risk?

"They're a group of mental health conditions that change your sense of reality. They make it hard to know what's real and what isn't. When you have these disorders, you might see and hear things that don't exist or believe things that aren't true. Scientists don't know exactly what causes psychotic disorders, but they've got some theories. Viruses, problems with how certain brain circuits work, extreme stress or trauma and some forms of drug abuse may play a role in some people. You may also be more likely to get a psychotic disorder if you have a family member who has one." This is from WebMD and copied word-for-word.