At the start of the 20th century there were only a dozen officially recognized mental health conditions.citation needed. By 1952 there were 192 and the Diagnostic and Statistical Manual of Mental Disorder, Fourth ion (DSM-IV) today lists 374. ClassificationMain article: Classification of mental disordersThe definition and classification of mental disorder is a key issue for the mental health professions and for users and providers of mental health services. Most international clinical documents use the term "mental disorder" rather than "mental illness". There is no single definition and the inclusion criteria are said to vary depending on the social, legal and political context. In general, however, a mental disorder has been characterized as a clinically significant behavioral or psychological pattern that occurs in an individual and is usually associated with distress, disability or increased risk of suffering. There is often a criterion that a condition should not be expected to occur as part of a person's usual culture or religion.

The term "serious mental illness" (SMI) is sometimes used to refer to more severe and long-lasting disorder. A broad definition can cover mental disorder, mental retardation, personality disorder and substance dependence. The phrase "mental health problems" may be used to refer only to milder or more transient issues.There are currently two widely established systems that classify mental disorders - Chapter V of the International Classification of Diseases (ICD-10), produced by the World Health Organization (WHO), and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) produced by the American Psychiatric Association (APA). Both list categories of disorder and provide standardized criteria for diagnosis. They have deliberately converged their codes in recent revisions so that the manuals are often broadly comparable, although significant differences remain. Other classification schemes may be in use more locally, for example the Chinese Classification of Mental Disorders.

Other manuals may be used by those of alternative theoretical persuasions, for example the Psychodynamic Diagnostic Manual.Some approaches to classification do not employ distinct categories based on cut-offs separating the abnormal from the normal. They are variously referred to as spectrum, continuum or dimensional systems. There is a significant scientific debate about the relative merits of a categorical or a non-categorical system. There is also significant controversy about the role of science and values in classification schemes, and about the professional, legal and social uses to which they are put. Disorders This section needs additional citations for verification.Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (June 2007) There are many different categories of mental disorder, and many different facets of human behavior and personality that can become disordered.The state of anxiety or fear can become disordered, so that it is unusually intense or generalized over a prolonged period of time.

Commonly recognized categories of anxiety disorders include specific phobia, Generalized anxiety disorder, Social Anxiety Disorder, Panic Disorder, Agoraphobia, Obsessive-Compulsive Disorder, Post-traumatic stress disorder. Relatively long lasting affective states can also become disordered. Mood disorder involving unusually intense and sustained sadness, melancholia or despair is know as Clinical depression (or Major depression), and may more generally be described as Emotional dysregulation. Milder but prolonged depression can be diagnosed as dysthymia.

Mental Disorder

Mental disorder or mental illness are terms used to refer to a psychological or physiological pattern that occurs in an individual and is usually associated with distress or disability that is not expected as part of normal development or culture. The recognition and understanding of mental disorders has changed over time. Definitions, assessments, and classifications of mental disorders can vary, but guideline criterion listed in the ICD, DSM and other manuals are widely accepted by mental health professionals. Categories of diagnoses in these schemes may include dissociative disorders, mood disorders, anxiety disorders, psychotic disorders, eating disorders, developmental disorders, personality disorders, and many other categories. In many cases there is no single accepted or consistent cause of mental disorders, although they are widely understood in terms of a diathesis-stress model and biopsychosocial model. Mental disorders have been found to be common, with over a third of people in most countries reporting sufficient criteria at some point in their life.

Mental health services may be based in hospitals or in the community. Mental health professionals diagnose individuals using different methodologies, often relying on case history and interview. Psychotherapy and psychiatric medication are two major treatment options, as well as supportive interventions. Treatment may be involuntary where legislation allows. Several movements campaign for changes to mental health services and attitudes, including the Consumer/Survivor Movement. There are widespread problems with stigma and discrimination. History Eight women representing prominent mental diagnoses in the nineteenth century.Main article: History of mental disordersA number of mental disturbances, such as melancholy, hysteria and phobia, were described long ago in Ancient Greece and Rome, while others such as schizophrenia may not have been recognized. Hippocrates considered the idea that mental illness may be related to biology.Psychiatric theories and treatments for mental illness developed in Muslim psychology and Islamic medicine in the medieval Islamic world from the 8th century, where the first psychiatric hospitals were built.

The Baghdad Hospital was run by the Persian physician Rhazes. Unlike most ancient and medieval societies which believed mental illness to be caused by either demonic possession or as punishment from a God, Islamic neuroethics held a more sympathetic attitude towards the mentally ill, as exemplified in Sura 4:5 of the Qur'an, which considers the mentally ill to be unfit to manage property but must be treated humanely and be kept under care by a guardian.Medieval Europe had focused on demonic possession as the explanation of aberrant behavior. Paracelsus used the word lunatic to describe behavior thought to be caused by the lunar effect. Many other terms for mental disorder that found their way into everyday use have been traced to initial use in the 16th and 17th centuries. Shakespeare and his contemporaries frequently depicted mental disorders in their plays. Conditions of "shell shock" came to be recognized in war veterans. From the early study of mental illness through individuals such as Philippe Pinel, Sigmund Freud, and Alois Alzheimer, much has changed in the development and understanding of mental illness and continues to change today.