Neurological

Neurology is the branch of medicine dealing with the nervous system and its disorders. Physicians specializing in the field of neurology are called neurologists. Surgical operations on the nervous system are performed by physicians with specialized training - neurosurgeons, and in some cases, interventional neuroradiologists.

Neurological disorders are disorders affecting the central nervous system (brain, brainstem and cerebellum), the peripheral nervous system (peripheral nerves - cranial nerves) included), or the autonomic nervous system (parts of which are located in both central and peripheral nervous system). Major conditions include:

• headache disorders such as migraine and tension headache (cluster headache)
• episodic conditions such as seizures and the epilepsies
• neurodegenerative disorders, the most common class being dementias, including Alzheimer's disease
• cerebrovascular disease, such as transient ischemic attacks, and strokes (ischemic or hemorrhagic)
• sleep disorders
• cerebral palsy
• bacterial, fungal, viral and parasitic infections of the central nervous system (encephalitis), brain envelopes (meningitis) and peripheral nerves (neuritis), such as brain abscess, herpetic meningoencephalitis, aspergilloma, cerebral hydatic cyst, tetanus, botulism
• neoplasms - tumors of the brain and its envelopes (brain tumors), spinal cord tumors, tumors of the peripheral nerves (neuroma)
• movement disorders such as Parkinson's disease, chorea, hemibalism
• demyelinating diseases of the central nervous system, such as multiple sclerosis, and of the periferal nervous system, such as Guillan-Barré syndrome and chronic demyelinating polyradyculoneuropathy (CIDP)
• spinal cord disorders - tumors, infections, trauma, malformations (e.g. myelocelle, meningomyelocelle, tethered cord)
• disorders of peripheral nerves, muscle and neuromuscular junctions
• traumatic injuries to the brain, spinal cord and peripheral nerves
• stupor and coma have a variety of causes (metabolic disturbances, intoxications, mechanical causes - any condition leading to a significant increase in intracranial pressure)

Neurologists are responsible for diagnosing and treating all of the above conditions, except for surgical interventions, which fall into the responsability of neurosurgeons, and in some cases interventional neuroradiologists. In some countries, additional legal responsibilities of a neurologist include making a finding of brain death when it is suspected that a patient is deceased, and filing the necessary paperwork for issuance of a death certificate.

Although many mental illnesses are believed to be neurological disorders affecting the central nervous system, traditionally they are being classified separately, and are treated by psychiatrists. In a 2002 review article in the American Journal of Psychiatry, Professor Joseph B. Martin, Dean of Harvard Medical School and a neurologist by training, wrote that 'the separation of the two categories is arbitrary, often influenced by beliefs rather than proven scientific observations. And the fact that the brain and mind are one makes the separation artificial anyway.' (Martin JB. The integration of neurology, psychiatry and neuroscience in the 21st century. Am J Psychiatry 2002; 159:695-704)

There are strong indications that neuro-chemical mechanisms play an important role in the development of, for instance, bipolar disorder and schizophrenia. As well, 'neurologcal' diseases often have 'psychiatric' manifestations, such as post-stroke depression, depression and dementia associated with Parkinson's disease, mood and cognitive dysfunctions in Alzheimer's disease, to name a few. Hence, there is no sharp distinction between neurology and psychiatry on a biological basis - this distinction has mainly practical reasons and strong historical roots (such as the dominance of Freud's psychoanalytic theory in psychiatric thinking in the first three quarters of the 20th century - which has since then been largely replaced by the focus on neurosciences - aided by the tremendous advances in genetics and neuroimaging recently.)

External links

• American Academy of Neurology
• brainblog: news about our knowledge of the brain and behavior.
• Journal Watch Neurology: collection of the most important neurology studies for practicing clinicians, summarized and with commentary.

See also

• History of neurology
• List of neurological disorders
• List of neurologists
• Clinical neurophysiology
• Psychiatry