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Autonomic nervous system
Nerves that control involuntary body functions of muscles, glands, and internal organs.
Blood vessels that let certain substances enter the brain tissue and keep other substances out.
Largest part of the brain; responsible for voluntary muscular activity, vision, speech, taste, hearing, thought and memory, among other functions.
Microscopic branching portion of a nerve cell; first part of the nerve cell to receive the nervous impulse.
A glial cell that lines the membranes within the brain and spinal cord and helps form cerebrospinal fluid.
Nervous system cell that is supportive and connective in function: Astrocyte, microglial cell, ependymal cell.
Excessive sensitivity or feeling, especially of the skin in response to touch or pain.
Portion of the brain beneath the thalamus; controls sleep, appetite, body temperature, and secretions from the pituitary gland.
Inflammation of the two thinner membranes (arachnoid and pia mater) surrounding the brain and spinal cord.
Lower part of the brain, closest to the spinal cord; controls breathing heartbeat, and size of blood vessels.
Congenital hernia (protrusion) of the spinal cord and meninges through a defect (gap) in the vertebral column. This defect is often associated with spina bifida.
Glial (neuroglial) cell that forms the myelin sheath covering the axon of a neuron.
Involuntary, autonomic nerves that regulate normal body functions, such as heart rate, breathing, and the muscles of the gastrointestinal tract.
Essential, functioning cells of any organ. Neurons (nerve cells) are the parenchyma of the nervous system.
Abnormal nervous sensation occurring without apparent cause. Examples are tingling, numbness or prickling sensations.
Peripheral nervous system
Nerves outside the brain and spinal cord; cranial, spinal, and autonomic nerves.
Network of nerves outside of the central nervous system; brachial, cervical, lumbosacral plexuses are examples.
Part of the brainstem anterior to the cerebellum, between the medulla and the rest of the brain. The pons connects the upper and lower portions of the brain.
Organ that receives nervous stimulation and passes it on to nerves that carry the stimulation to the brain and spinal cord; skin, ears, eyes and taste buds.
Extends from the base of the spine down the thigh, lower leg, and foot. Sciatica is pain along the course of the nerve.
Thirty-one pairs of nerves arising from the spinal cord. Each spinal nerve affects a particular area of the skin.
Autonomic nerves that activate responses in times of stress; heartbeat, respiration, and blood pressure are affected.
Main relay center of the brain; located in the central region or diencephalon of the brain.
Flashes of stab like pain along the course of a branch of the trigeminal nerve (5th cranial nerve). The trigeminal nerve has branches to the eye, upper jaw and lower jaw.
Minor form of seizure, consisting of momentary clouding of consciousness and loss of contact with the environment.
Brain disorder marked by progressive, gradual mental deterioration (dementia) along with personality changes and impairment of daily functioning.
Amyotropic lateral sclerosis
Degenerative disorder of motor neurons in the spinal cord and brainstem and resulting in total body paralysis.
Weakening of an arterial wall, which may lead to hemorrhage and cerebrovascular accident (stroke).
Brain tumor composed of astrocytes (glial cells). The most serious of these tumors is a glioblastoma multiforme (Grades III and IV malignant brain tumor).
X-ray record of blood vessels in the brain after intravenous injection of contrast material.
Temporary brain dysfunction (brief loss of consciousness) after injury; usually clearing within 24 hours.
Bruising of brain tissue as a result of direct trauma to the head; neurologic disorder persists longer than 24 hours.
Partial paralysis and muscular coordination caused by loss of oxygen or blood flow to the cerebrum during pregnancy or in the perinatal period.
Cerebrospinal fluid analysis
Samples of cerebrospinal fluid are examined for blood cells, protein, glucose, tumor cells, bacteria and other substances.
Cross-sectional x-ray imaging of an organ (such as the brain or spinal cord), with or without contrast material.
Neurotransmitter in the central nervous system; deficient in patients with Parkinson disease.
Sound waves are used to detect blood flow in arteries within the brain and leading to the brain.
Blood clot that is carried by the bloodstream from one area of the body to another where it blocks a blood vessel.
Disease of the brain (dementia) caused by infection with the human immunodeficiency virus (HIV), which causes AIDS (acquired immunodeficiency syndrome).
Hereditary disorder affecting the cerebrum and involving abrupt, involuntary, jerking movements and mental deterioration in later stages.
The two thinner membranes—the pia mater and the arachnoid membrane—surrounding the brain and spinal cord.
Withdrawal of cerebrospinal fluid from the subarachnoid space between two lumbar vertebrae; spinal tap.
Magnetic resonance imaging
Magnetic and radio waves create an image of an organ three planes of the body. The brain and spinal cord can be imaged to detect lesions.
Hernia of the meninges through a defect or space between vertebrae; a form of spina bifida cystica.
Chronic neurologic disorder marked by destruction of the myelin sheath on neuronal axons in the CNS and replacement by plaques of sclerotic tissue.
Degeneration of nerve cells that produce the neurotransmitter, dopamine in the brain; leads to tremors, weakness of muscles, and slowness of movement.
Positron emission tomography
Computerized radiologic procedure using radioactive glucose or oxygen to image the metabolic activity of cells, such as brain cells.
Viral (herpes zoster) illness that affects peripheral nerves; produces blisters and pain on the skin overlying the path of peripheral nerves.
Congenital defect in the lumbar spinal column caused by imperfect union of vertebral parts; spinal cord and meninges may herniate through the vertebral gap.
Use of a specialized instrument using three-dimensional coordinates to locate the site to be operated on.
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