The condition you are referring to is called "psychosis." Psychosis is a mental health disorder characterized by a loss of contact with reality, which may involve experiencing hallucinations (seeing, hearing, or feeling things that are not present) and/or delusions (strongly held false beliefs despite evidence to the contrary). It can be caused by various factors, including severe stress, certain psychiatric disorders (e.g., schizophrenia), substance abuse, and medical conditions. If someone is experiencing symptoms of psychosis, it is essential to seek professional help and support from a mental health expert.