According to DSM-5, to be diagnosed as being depressed a patient has to display five or more of the following symptoms: depressed mood, diminished pleasure in most or all activities (anhedonia), significant weight loss, insomnia or hypersomnia, psychomotor agitation or retardation, fatigue, diminished ability to think or concentrate, recurrent thought of death. These symptoms have to be present at the same time for at least 2 weeks and to be a change from previous functioning. At least one of the symptoms has to be depressed mood or anhedonia, making the latter a core symptom of the
