A psychiatrist is a physician who specializes in the diagnosis and treatment of mental and cognitive disorders. All psychiatrists are trained in diagnostic evaluation of psychiatric conditions as defined by the DSM, and in psychotherapy as well. In the past it was common to have physicians who were also trained in psychoanalysis, however this has since become less common in the last twnty years. Most modern psychiatrist in the United States are members of the American Psychiatric Association.
As part of their psychiatric evaluation of the patient, only psychiatrists are authorized to prescribe psychiatric medication, conduct physical examinations, order and interpret laboratory tests and electroencephalograms, and may order brain imaging studies such as computed tomography or computed axial tomography (CT/CAT Scan), magnetic resonance imaging (MRI), and positron emission tomography scanning. However, a number of states have passed legistation in the last decade to grant psychologists these powers, as the mental health field has experiencing a significant shortage of psychiatrists.
In the Ancient World and Dark Ages
The term was first coined by the German physician Johann Christian Reil in 1808, and literally means the 'medical care of the soul/mind'; from the Koine Greek 'psukhē', meaning: intelligble soul/mind; and the suffix '-iatry', meaning: medical care; from the Attic Greek. 'iātrikos': to heal). However, it held common use as an unspecified division of medicine before that time. Early Greek medicine is not explictly interested in psychiatry as an independent discipline, and it is rarely noted by medical forerunners like Hippocrates and Galen.
Specialist hospitals for the practice of psychiatry were built in Baghdad as early as 705 AD, followed by one in Fes in the early 8th century, and Cairo in the year 800 AD. Physicians who wrote on mental disorders and their treatment in the Medieval Islamic period included Muhammad ibn Zakarīya Rāzi (Rhazes), the Arab physician Najab ud-din Muhammadand Abu Ali al-Hussain ibn Abdallah ibn Sina, known in the Western world as Avicenna. Islamic study of psychiatric medicine and theories of mind were some of the most advanced of the period.
Medieval Period and Englightenment in Europe
In contrast, specialist hospitals that were built in medieval Europe, from the 13th century to treat mental disorders, were utilized only as custodial institutions and did not provide any type of treatment to their patients. Founded in the 13th century, Bethlem Royal Hospital in London is one of the oldest lunatic asylums. By 1547, the City of London acquired the hospital and continued its function until 1948, afterwhich it passed to the care of the National Health Service and is an NHS Foundation Trust.
In 1621, Oxford University mathematician, astrologer, and scholar Robert Burton published the English language 'The Anatomy of Melancholy', this would be the initial guide of English Psychiatry for centuries, as it classifies disorders by: kinds, causes, symptomes, prognostickes, and cures.
In 1656, Louis XIV of France created a public system of hospitals for those suffering from Insanity, but as in England, no real treatment was applied to those who suffered. In 1713, the Bethel Hospital Norwich was opened, the first purpose-built asylum in England, founded by Mary Chapman. In 1758 English physician William Battie wrote his Treatise on Madness which called for treatments to be utilized in asylums.
Thirty years later, then ruling monarch in England George III was known to be suffering from an unknown mental disorder. Following the King's remission in 1789, mental illness came to be seen as something which could be treated and cured by medical authorities. The French doctor Philippe Pinel introduced humane treatment approaches to those suffering from mental disorders. As a result of his work, the Governor of the Bicêtre psychiatric hospital in Paris released psychiatric patients from their chains in 1793, beginning what has been called the 'bright epoch of psychiatry'. At the York Retreat, a Quaker-run asylum in England which opened in 1796, a form of moral treatment evolved independently from Pinel under the lay stewardship of the tea and coffee merchant William Tuke. Tuke's Retreat became a model throughout the world for humane and moral treatment of patients suffering from mental disorders. The York Retreat inspired similar institutions in the United States, most notably the Brattleboro Retreat and Friends Hospital.
In the early 1800's, psychiatry made a significant advance in diagnosis of mental illness by broadening the category of mental disease to include Neurosis, in addition to disease level delusion or irrationality. Jean-Étienne Dominique Esquirol, a student of Pinel, made the first elaboration of what was to become our modern clinical definition of depression, lypemania, and Monomania.
Modern psychiatry attempts to combine the use of psychoactive medication and psychotherapy in treatment, but current practice also includes widely ranging variety of other potential modalities. Treatment may be delivered on an inpatient or outpatient basis, depending on the severity of functional impairment or on other aspects of the psychiatric disorder in question. Research and treatment within psychiatry as a whole are conducted on an interdisciplinary basis, sourcing an array of sub-specialties and theoretical approaches.
The term Alienist was used frequently to refer to both American/European psychiatrists and psychologists as late as the early 20th century. It is currently considered archaic in medical circles, and is not commonly employed.