The diagnosis and classification of psychological disorders is essential in studying and treating psychopathology. Although challenging, it is essential for psychologists and mental health professionals to agree on what kinds of inner experiences and behaviors constitute the presence of a psychological disorder.

Harmful dysfunction describes the view that psychological disorders result from the inability of an internal mechanism to perform its natural function. Many of the features of harmful dysfunction conceptualization have been incorporated in the APA’s formal definition of psychological disorders.

psychological disorder — condition characterized by abnormal thoughts, feelings, and behaviors. psychopathology — study of psychological disorders, including their symptoms, causes, and treatment; manifestation of a psychological disorder. presence of a psychological disorder — signaled by significant disturbances in thoughts, feelings, and behaviors; these disturbances must reflect some kind of dysfunction (biological…. harmful dysfunction — model of psychological disorders resulting from the inability of an internal mechanism to perform its natural function.