neurology

—neurological /noor'euh loj"i keuhl, nyoor'-/, adj. —neurologically, adv.

/noo rol"euh jee, nyoo-/, n.

the science of the nerves and the nervous system, esp. of the diseases affecting them.

[1675-85; < NL neurologia. See NEURO-, -LOGY]

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Medical specialty concerned with nervous system function and disorders.

Clinical neurology began in the mid-19th century, when mapping of the functional areas of the brain first began and understanding of the causes of conditions such as epilepsy improved. The development of electroencephalography in the 1920s aided in the diagnosis of neurological disease, as did the development of computed axial tomography in the 1970s and nuclear magnetic resonance imaging in the 1980s. In addition to dealing with physical disorders (e.g., tumours, trauma), neurology is unique among medical specialties in its intersection with psychiatry. Greater understanding of the brain chemistry of disorders such as schizophrenia and depression has led to a wide array of effective drugs that nevertheless work best in conjunction with psychotherapy. Side effects of drug or surgical therapy can be serious, and many nervous system disorders have no effective treatment.

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▪ medicine

      medical specialty concerned with the nervous system and its functional or organic disorders. Neurologists diagnose and treat diseases and disorders of the brain, spinal cord, and nerves.

      The first scientific studies of nerve function in animals were performed in the early 18th century by English physiologist Stephen Hales (Hales, Stephen) and Scottish physiologist Robert Whytt. Knowledge was gained in the late 19th century about the causes of aphasia, epilepsy, and motor problems arising from brain damage. French neurologist Jean-Martin Charcot (Charcot, Jean-Martin) and English neurologist William Gowers (Gowers, William Timothy) described and classified many diseases of the nervous system. The mapping of the functional areas of the brain through selective electrical stimulation also began in the 19th century. Despite these contributions, however, most knowledge of the brain and nervous functions came from studies in animals and from the microscopic analysis of nerve cells.

      The electroencephalograph (electroencephalography) (EEG), which records electrical brain activity, was invented in the 1920s by Hans Berger. Development of the EEG, analysis of cerebrospinal fluid obtained by lumbar puncture (spinal tap), and development of cerebral angiography allowed neurologists to increase the precision of their diagnoses and develop specific therapies and rehabilitative measures. Further aiding the diagnosis and treatment of brain disorders were the development of computerized axial tomography (CT) scanning in the early 1970s and magnetic resonance imaging (MRI) in the 1980s, both of which yielded detailed, noninvasive views of the inside of the brain. (See brain scanning.) The identification of chemical agents in the central nervous system and the elucidation of their roles in transmitting and blocking nerve impulses have led to the introduction of a wide array of medications that can correct or alleviate various neurological disorders including Parkinson disease (parkinsonism), multiple sclerosis, and epilepsy. Neurosurgery, a medical specialty related to neurology, has also benefited from CT scanning and other increasingly precise methods of locating lesions and other abnormalities in nervous tissues.

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