Nervous system

The nervous system is the system of nerves and sensory organs throughout the body. There are various sub-parts of the nervous system. The Central Nervous System (CNS) involves the Brain and Spinal Cord. The Peripheral Nervous System is the nerves in the limbs and peripheral areas of the body. The Autonomic Nervous System is the nerves controlling various automatic functions of the body (e.g. digestion, breathing). Nervous system symptoms include pain, numbness, tingling, nerve pain, movement symptoms, and so on. Read more about: Nerve Symptoms, Nerve Disorders

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The Nervous Systems

The central nervous system (CNS) refers to the brain and spinal cord together. The peripheral nervous system refers to the cervical, thoracic, lumbar, and sacral nerve trunks leading away from the spine to the limbs. Messages related to function (such as movement) or dysfunction (such as pain) travel from the brain to the spinal cord and from there to other regions in the body and back to the brain again. The autonomic nervous system controls involuntary functions in the body, like perspiration, blood pressure, heart rate, or heart beat. It is divided into the sympathetic and parasympathetic nervous systems. The sympathetic and parasympathetic nervous systems have links to important organs and systems in the body; for example, the sympathetic nervous system controls the heart, blood vessels, and respiratory system, while the parasympathetic nervous system controls our ability to sleep, eat, and digest food.

The peripheral nervous system also includes 12 pairs of cranial nerves located on the underside of the brain. Most relay messages of a sensory nature. They include the olfactory (I), optic (II), oculomotor (III), trochlear (IV), trigeminal (V), abducens (VI), facial (VII), vestibulocochlear (VIII), glossopharyngeal (IX), vagus (X), accessory (XI), and hypoglossal (XII) nerves. Neuralgia, as in trigeminal neuralgia, is a term that refers to pain that arises from abnormal activity of a nerve trunk or its branches. The type and severity of pain associated with neuralgia vary widely.

Source: NINDS (NIH)1

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What are the parts of the nervous system?

The nervous system consists of two main parts: the central nervous system and the peripheral nervous system:

The brain sends messages through the spinal cord and nerves of the peripheral nervous system to control the movement of the muscles and the function of internal organs.

The basic working unit of the nervous system is a cell called a neuron. The human brain contains about 100 billion neurons. A neuron consists of a cell body containing the nucleus, and special extensions called axons (pronounced AK-sonz) and dendrites (pronounced DEN-drahytz).

Source: NICHD (NIH)2

Introduction: Nervous system

What health-related functions are regulated by the nervous system?

The nervous system plays a role in nearly every aspect of our health and well-being—from everyday activities such as waking up, to simple activities such as breathing, to complex processes such as thinking, reading, remembering, and feeling emotions.

Functions that are regulated by the nervous system include (but are not limited to):

Neuroscientists study the nervous system to better understand both its healthy and diseased states. Studying and understanding the nervous system is important because it affects so many areas of human health and well-being.1

Source: NICHD (NIH)3

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Nervous System: The entire nerve apparatus, composed of a central part, the brain and spinal cord, and a peripheral part, the cranial and spinal nerves, autonomic ganglia, and plexuses. (Stedman, 26th ed)4

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Nervous system adverse event: An adverse event that occurs in nervous system.5

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References

  1. Source: NINDS (NIH): ninds.nih.gov/ disorders/ chronic_pain/ detail_chronic_pain.htm
  2. Source: NICHD (NIH): nichd.nih.gov/ health/ topics/ neuro/ conditioninfo/ Pages/ parts.aspx
  3. Source: NICHD (NIH): nichd.nih.gov/ health/ topics/ neuro/ conditioninfo/ Pages/ functions.aspx
  4. Source: MeSH (U.S. National Library of Medicine)
  5. Source: OAE Ontology

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Note: This site is for informational purposes only and is not medical advice. See your doctor or other qualified medical professional for all your medical needs.