Answer:
schizophrenia
Step-by-step explanation:
Schizophrenia is a chronic and serious mental disorder that affects the way a person thinks, feels and behaves. It causes changes in behavior, affective indifference, confused thoughts and difficulties in relating to people. People with schizophrenia may seem to have lost touch with reality. Although schizophrenia is not as common as other mental disorders, the symptoms can be very disabling.
It is common for people with this disorder to have distorted thoughts and perceptions, to hear voices, to have unrealistic thoughts, and to see things that do not exist. Derek shows many of these signs, which may indicate that he has schizophrenia.