What Is Mental Illness?

The question of what constitutes mental illness is not quite as simple as it seems. For the purposes of treatment by the psychiatric and mental health communities, there are defined criteria for the diagnosis of medically accepted mental Illnesses which are described in detail in the Diagnostic and Statistics Manual Of Mental Disorders (currently the fourth edition DSMIV TR) which forms the basis for almost all mental health treatment conceptualization in the US. However, this diagnostic manual is always a work in progress, and the conceptualization of mental illness will continue to change and evolve with the advances in our knowledge about the nature of mental illness and effective treatments.

Mental illness in general are conditions which are a clinically significant psychological syndrome or pattern in a person that is associated with distress, disability of functioning or increased risk of death, pain, disability, or loss of freedom. This rather abstract definition is based on that contained in the DSMIV TR. In simpler terms, the answer can be described as conditions that cause problems in some combination of a person’s thinking abilities, emotional functioning, social functioning, or ability to sustain age appropriate independence.

Mental Illness diagnosis  is generally broken into a variety of subtypes with multiple specific conditions that make up each subtype. The major subtypes include disorders usually first diagnosed in infancy or childhood, cognitive disorders with impairment of thinking abilities, mental disorders due to other medical conditions, substance usage disorders, schizophrenia and other psychotic disorders, mood disorders, anxiety disorders, somatic disorders of physical symptoms due to a psychological condition, factitious disorders in which symptoms are feigned or exaggerated to assume a sick role, dissociative disorders, sexual and gender identity disorders, eating disorders, sleep disorders, impulse control disorders, and personality disorders. There are also a group of associated conditions that my be the focus of treatment but do not constitute a diagnosed mental disorder.