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Psychosurgery, also called neurosurgery for mental disorder (NMD), is the neurosurgical treatment of mental disorder. Psychosurgery has always been a controversial medical field.〔 The modern history of psychosurgery begins in the 1880s under the Swiss psychiatrist Gottlieb Burckhardt. The first significant foray into psychosurgery in the twentieth century was conducted by the Portuguese neurologist Egas Moniz who during the mid-1930s developed the operation known as leucotomy. The practice was enthusiastically taken up in the United States by the neuropsychiatrist Walter Freeman and the neurosurgeon James W. Watts who devised what became the standard prefrontal procedure and named their operative technique lobotomy, although the operation was called leucotomy in the United Kingdom. In spite of the award of the Nobel prize to Moniz in 1949, the use of psychosurgery declined during the 1950s. By the 1970s the standard Freeman-Watts type of operation was very rare, but other forms of psychosurgery, although used on a much smaller scale, survived. Some countries have abandoned psychosurgery altogether; in others, for example the US and the UK, it is only used in a few centres on small numbers of people with depression or obsessive-compulsive disorder (OCD).〔Neurosurgery working group 2000 ''Neurosurgery for mental disorder''. London: Royal College of Psychiatrists〕 In some countries it is also used in the treatment of schizophrenia and other disorders.〔N. Zamiska 2007 (In China, brain surgery is pushed on the mentally ill ). ''Wall Street Journal'', 2 November〕 Psychosurgery is a collaboration between psychiatrists and neurosurgeons. During the operation, which is carried out under a general anaesthetic and using stereotactic methods, a small piece of brain is destroyed or removed. The most common types of psychosurgery in current or recent use are capsulotomy, cingulotomy, subcaudate tractotomy and limbic leucotomy. Lesions are made by radiation, thermo-coagulation, freezing or cutting.〔 About a third of patients show significant improvement in their symptoms after operation.〔 Advances in surgical technique have greatly reduced the incidence of death and serious damage from psychosurgery; the remaining risks include seizures, incontinence, decreased drive and initiative, weight gain, and cognitive and affective problems.〔 Currently, interest in the neurosurgical treatment of mental illness is shifting from ablative psychosurgery (where the aim is to destroy brain tissue) to deep brain stimulation (DBS) where the aim is to stimulate areas of the brain with implanted electrodes. ==Medical uses== All the forms of psychosurgery in use today (or used in recent years) target the limbic system, which involves structures such as the amygdala, hippocampus, certain thalamic and hypothalamic nuclei, prefrontal and orbitofrontal cortex, and cingulate gyrus — all connected by fibre pathways and thought to play a part in the regulation of emotion.〔Clinical resource and audit group 1996 ''Neurosurgery for mental disorder''. Edinburgh: Scottish Office〕 There is no international consensus on the best target site.〔 Anterior cingulotomy was first used by Hugh Cairns in the UK, and developed in the US by H.T. Ballantine jnr.〔 In recent decades it has been the most commonly used psychosurgical procedure in the US.〔 The target site is the anterior cingulate cortex; the operation disconnects the thalamic and posterior frontal regions and damages the anterior cingulate region.〔 Anterior capsulotomy was developed in Sweden, where it became the most frequently used procedure. It is also used in Scotland and Canada. The aim of the operation is to disconnect the orbitofrontal cortex and thalamic nuclei.〔 Subcaudate tractotomy was the most commonly used form of psychosurgery in the UK from the 1960s to the 1990s. It targets the lower medial quadrant of the frontal lobes, severing connections between the limbic system and supra-orbital part of the frontal lobe.〔 Limbic leucotomy is a combination of subcaudate tractotomy and anterior cingulotomy. It was used at Atkinson Morley Hospital London in the 1990s〔 and also at Massachusetts General Hospital. Amygdalotomy, which targets the amygdala, was developed as a treatment for aggression by Hideki Narabayashi in 1961 and is still used occasionally, for example at the Medical College of Georgia. There is debate about whether deep brain stimulation (DBS) should be classed as a form of psychosurgery. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「psychosurgery」の詳細全文を読む スポンサード リンク
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