In this lecture, Dr Jones will discuss the clinically important points related to psychotic disorders. Psychotic disorders are severe mental disorders that cause abnormal thinking and perceptions. People with psychoses lose touch with reality. Two of the main symptoms are delusions and hallucinations. Delusions are false beliefs, such as thinking that someone is plotting against you or that the TV is sending you secret messages. Hallucinations are false perceptions, such as hearing, seeing, or feeling something that is not there. Schizophrenia is one type of psychotic disorder. Psychosis can also be caused by alcohol, some drugs, brain tumours, brain infections, stroke and mood disorders such as bipolar. This lecture will discuss Schizophrenia, Brief Psychotic disorder and Schizophreniform disorders.