Psychopathology- the scientific study of mental disorders Criteria for Mental Disorders Maladaptive Behavior ? behavior that causes harm by making it difficult to fulfill the normal functions of everyday life. Personal Distress ? a person?s individual perception of his or her own emotional distress. Atypical Behavior ? behavior that deviates from what is considered socially or culturally normal. Violation of Cultural Norms ? behavior that so deviates from what is culturally accepted that it is considered unacceptable and intolerable. Early Theories Abnormal behavior was evil spirits trying to get out. Trephining was often used. Diagnostic Statistical Manual of Mental Disorders: the big book of disorders. DSM will classify disorders and describe the symptoms.