Psychosis is a medical name for a state of mind that can happen with several types of mental illness. People who have a psychotic episode are often described as 'losing touch with reality'. People with psychosis may have altered perception, thinking and emotions. They may see and feel things differently than normal people and have hallucinations. They may ... have delusional beliefs or have paranoid thoughts and may behave differently from normal. Psychosis may affect speech and language so the person may seem to communicate in unusual ways.