Overall picture: Several symptoms of mental illness are related to emotional problems Patients with major depressive disorder, borderline personality disorder, and substance abuse disorder have problems with emotions. Deficits in the ability to regulate emotions and to understand emotional information seem to be the most conspicuous characteristics in patients with mental disorders. Patients with different mental disorders vary regarding their specific emotional deficits. When focusing in detail on persons with mental disorder, we found variation in terms of the specific deficits, e.g., patients with depressive disorder had significantly less difficulties in understanding emotional information than persons with borderline personality disorder or substance abuse disorder. Persons with substance abuse disorder showed the largest impairment. Emotional deficits seem to be more than a general phenomenon in mental illness.