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Medical Dictionary - Nervous

accessory nerveEither of two cranial nerves which are important for swallowing, speech and some head and shoulder movements.
acrophobiaFear of heightsak'ro-fo´be-ah
acupunctureTherapy for treating pain and disease by inserting needles along specific pathways or meridians.
ADAlzheimer disease
ADDattention deficit disorder
ADHDattention deficit-hyperactivity disorder
adjustment disordersMaladaptive reactions to a stressful event.
adrenergic fibersNerve fibers liberating catecholamines at a synapse after an impulse.
adrenergic neuronsNeurons whose primary neurotransmitter is epinephrine.
affectThe emotional reaction to an experience or thought.
agnosiaThe inability to comprehend or recognize the importance of various forms of stimulation.
-agrasevere pain
agraphiaInability to write due to a cerebral injury or less commonly, due to emotional factors.
akinetic mutismA syndrome characterized by a silent and inert state without voluntary motor activity despite alertness.
alexiaInability to read despite preservation of the ability to write. The patient cannot recognize letters and words.
alprazolamA compound used to treat anxiety.
Alzheimer diseaseType of dementia that causes problems with memory, thinking, and behavior.awltz'hī-mĕr
amnesiaLoss of memory due to brain injury or emotional trauma.
amphetamineA powerful group of drugs that stimulate the central nervous system. Amphetamines reduce feelings of fatigue and increase alertness.
amyotrophic lateral sclerosisA neurological disease causing muscle weakness and impacting physical function. Commonly called ALS.ā′mī·ōtrof′ik
analgesiaWithout pain or decreased pain.
analgesicsA compound that relieves pain.
anesthesiaThe loss of feeling or sensation, particularly pain.
anesthesiologyA specialty concerned with the study of anesthetics and anesthesia.
anestheticMedication that causes temporary loss of″es-thet´ik
anestheticsAgents that are capable of inducing a total or partial loss of sensation, especially tactile sensation and pain. They may act generally or locally.
angerA strong emotional feeling of displeasure aroused by being interfered with, injured or threatened.
anhedoniaInability to experience happiness or pleasure. It is a symptom of many psychotic disorders.
anomiaAn inability to name people and objects that are correctly comprehended.
anticonvulsantsDrugs used to prevent seizures or reduce their severity.
antidepressantsDrugs that prevent or relieve depression.
antidromicConducting nerve impulses in a direction opposite from normal.
antipsychoticAn agent used to control severe mental disorders.
antisocial A personality disorder characterized by a disregard for individual rights or laws.
anxietyFeeling or emotion of dread, apprehension, or fear without apparent stimulus.
apathyLack of emotion or emotional expression; disinterest.
aphasiaImpairment of language or speech comprehension.ah-fa´zhah
apraxiaDisorders characterized by the inability to make skilled, purposeful movements due to a cerebral disease.
aptitude testsStandardized tests designed to predict an individual's learning ability or performance.
aquaphobiaAn irrational fear of water.
arachnoidA delicate membrane covering the brain and spinal cord. It lies between the pia mater and the dura mater.
arachnoiditisAcute or chronic inflammation of the arachnoid membrane, resulting in pain and neurological abnormalities.
arousalA state of alertness due to stimulation.
asperger syndromeA developmental disorder whose essential features are persistent impairment in reciprocal social interactions, and restricted, repetitive patterns of behavior, interests, or activities and impairment in language and communications skills.
assertivenessStrongly insistent, self-assured behavior.
astrocyteA large, star shaped cell. Found throughout the central nervous system.
astrocytomaA type of brain tumor.
atelo-incomplete, imperfect
attentionMentally focusing on a specific object, issue or activity. The act of concentrating.
autismA group of developmental disabilities that can cause significant social, communication and behavioral´tizm
autonomicThe ability to function without external influence.
autonomic nervous systemThe part of the nervous system that regulates involuntary body functions. The enteric nervous system; parasympathetic nervous system; and sympathetic nervous system taken together.
autophagiaBiting or eating one's own flesh.
autosuggestionSuggestion coming from the subject himself.
aversion therapyA treatment that suppresses undesirable behavior by simultaneously exposing the subject to unpleasant consequences.
avoidanceA psychological or physical defense mechanism for avoiding a noxious experience.
axonNerve fiber that conduct impulses away from the neuron cell body.
BACblood alcohol concentration
barbiturateA sedative that depresses respiratory rate, blood pressure, temperature and the central nervous system.
basal gangliaLarge grey masses at the base of the cerebral hemisphere.
Bell's PalsyTemporary facial paralysis, 7th cranial nerve. Sudden onset. Usually one-side asymmetry.
benzocaineA local anesthetic applied topically.
bipolar disorderA major affective disorder marked by severe mood swings (manic or major depressive episodes) and a tendency to remission and recurrence.
bondingThe emotional attachment of mother-child or individuals to pets.
brainA highly developed part of central nervous system that is contained within the cranium. It consists of cerebrum, cerebellum and other structures in the brain stem.
carotid ultrasonographyA diagnostic imaging technique to reveal structural details of the carotid arteries.kah-rot´id
cataractA clouding of the eye's lens.kat´ah-rakt kat´ah-rakt]
catatoniaA neuropsychiatric disorder characterized by the patient becoming mute or immobile with extreme muscular rigidity.
cauda equinaThe lower part of the spinal cord consisting of the lumbar, sacral, and coccygeal nerve roots.
caus/oburn, burning
causalgiaA complex regional pain syndrome characterized by burning pain and marked sensitivity to touch in the distribution of an injured peripheral nerve.kaw-zal´jah
CBTcognitive behavioral therapy
central nervous systemThe main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.
cerebell/ocerebellum (posterior section of brain)
cerebellumThe part of brain located behind the brainstem in the posterior base of skull (posterior cranial fossa). It coordinates voluntary muscle activity, balance and tone.
cerebral contusionA bruise of the brain tissue . Frequently caused by a blow to the head.
cerebral edemaAn abnormal accumulation of fluid in brain tissue. Brain swelling.
cerebral hemorrhageBleeding into one or both cerebral hemispheres.
cerebral palsyA chronic childhood disorder that affects muscle tone, movement, and motor skills.
cerebrospinal fluidA watery fluid that is continuously produced in the choroid plexus and circulates around the surface of the brain, the spinal cord and in the cerebral ventricles.
cerebrovascular accidentA stroke. It is caused by the interruption of the brain’s blood supply, usually because a blood vessel bursts or is blocked by a clot, or a space-occupying lesion such as a tumor.
cerebrumThe largest, uppermost part of the brain. Responsible for initiating and coordinating all voluntary body activity. The cerebral cortex is responsible for intellectual activities.
cervical radiculopathyA pinched nerve. It occurs when a nerve in the neck is irritated as it leaves the spinal canal.rah-dik″u-lop´ah-the
claustrophobiaThe irrational fear of confined spaces.klaws″tro-fo´be-ah
CNScentral nervous system
comaA deep state of unconsciousness. No voluntary motor signs.ko´mah]
concuss/oshaken together
concussionA traumatic brain injury. Measure severity by universal Glasgow Coma Scale (GCS)kon-kush´un
conditioningLearning that takes place when a conditioned stimulus is paired with an unconditioned stimulus.
contus/oto bruise
CPcerebral palsy
CRconditioned reflex
-crasiamixture, loss of control
CSFcerebrospinal fluid
CVAcerebrovascular accident
deliriumA state of mental confusion that can occur due to illness, surgery or using certain medications.dĕ-lēr´e-um
delirium tremensThe most severe form of alcohol withdrawal, causing confusion, irregular heart rate, and sweating.dĕ-lēr´e-um trē′mənz
delusionA belief that is clearly false.dĕ-lū'zhŭn
dementiaA group of symptoms caused by brain disorder. Not a specific disease. Causes are peripheral vascular disease, stroke, toxins, or Alzheimer's.dĕ-men´shah
dendriteShort branches of the nerve cell body that receive stimuli from other neurons.
depersonalizationA feeling of unreality concerning the self or the environment.
diplegiaParalysis involving both sides of the body.
dopamineA central nervous system neurotransmitter.
DTsdelirium tremens
dur/ohard, dura mater
dura materThe dense, leathery membrane covering and protecting the brain and spinal cord.du´rah ma´ter
dyslexiaA common condition that affects the way the brain processes written and spoken language. dis-lek´se-ah
echoencephalographyThe use of ultrasound waves to study brain structures. ek′ō·ensef′əlog′rəfē
ECTelectroconvulsive therapy
efferent pathwaysThe route of nerve structures carrying impulses away from a nerve center toward a peripheral site.
eideticPertaining to the ability to accurately visualize events or objects from experience.
electroencephalographyA test to measure the electrical activity of the brain.ilek′trō·ensef′əlog′rəfē
encephalitisA inflammation of the brain. Symptoms include headache, fever, vomiting, stiff neck and lethargy.en-sef″ah-li´tis
ependymaA thin membrane that lines the cerebral ventricles and the central canal of the spinal cord.
epiduralOn or over the dura mater.
epidural anesthesiaA regional anesthesia that blocks pain.ep'i-dūr'ăl an'es-thē'zē-ă
epilepsyA general term for conditions with recurring seizures.ep´ĭ-lep″se
epineuriumThe sheath of a peripheral nerve.
ESTelectroshock therapy
esthes/onerve sensation, feeling
-esthesiasensation, feeling
factitious disorderConditions in which a person deliberately and consciously acts as if he or she has a physical or mental illness when he or she is not really sick. Known as Munchausen Syndrome.fak-tish´us
frontal lobeThe part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.
ganglionA structure containing an aggregation of nerve cell bodies located in the peripheral nervous system.
glasgow coma scaleA scale for measuring level of consciousness, especially after craniocerebral injury
-graphyprocess of recording
Guillain-Barre syndromeA disorder in which the immune system attacks the nerves. A rare disease, usually preceded by a viral infectiongē-yan[h]'
hallucinationSensing things while awake that appear to be real, but instead have been created by the mind, common in delirium.hah-loo″sĭ-na´shun
headachePain in the cranial region.
hemorrhagic strokeA stroke that occurs when a weakened blood vessel ruptures. Also called an aneurysm.hem″o-raj´ik
hippocampusA curved elevation of gray matter extending the entire length of the floor of the temporal horn of the lateral ventricle (see also temporal lobe). It has a central role in memory processes.
hydrocephalusThe buildup of excessive cerebrospinal fluid in the brain. hi″dro-sef´ah-lus
hyperesthesiaHyperesthesia is a condition in which someone becomes highly sensitized to sensory stimuli. hi″per-es-the´zhah
hypnosisA state of increased receptivity to suggestion and direction, initially induced by the influence of another person.
hypochondriaAnxiety about one's own health and belief that one is likely to become ill even though there is no medical evidence of illness.
hypochondriasisAn overwhelming fear of having a serious disease.hi″po-kon-dri´ah-sis
hysteriaExcessive or uncontrollable emotion, such as fear or panic.
ICPintracranial pressure
interneuronsGroups or combinations of neurons between sensory and motor neurons that govern coordinated activity.
intracranial hematomaBlood accumulation within the brain or between the brain and the skull,in'tră-krā'nē-ăl hem'ŏr-ăj
IQintelligence quotient
ischemic strokeThe main type of stroke. Occur when a blood vessel that supplies blood to the brain is blocked by a blood clot. is-kē'mik
klept/oto steal
lethargyA condition of tiredness, fatigue, or lack of energy.leth´er-je
LOClevel/loss of consciousness
log-speech, words
logo-words, speech
LPlumbar puncture
MAmental age
maniaAn abnormally excessive elated, enthusiastic mental state.
-maniaobsession with
MBDminimal brain dysfunction
median nerveA major nerve of the arm, suppling sensory and motor innervation to parts of the forearm and hand.
medulla oblongataThe lower portion of the brain stem. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.
megalomaniaDelusions of grandeur or exaggerated personal importance, wealth or power.
memoryThe mental functions of learning, retention, recall and recognition.
meningesThe three membranes that envelop the brain and the spinal cord.
meningiomaA relatively common neoplasm of the central nervous system.
meningitisAn acute inflammation of the protective membranes covering the brain and spinal cord. May be viral or″in-ji´tis
meningoceleSurgery to repair birth defects of the spine and spinal membranes.mĕ-ning´go-sēl
merkel cellsModified epidermal cells located in the stratum basale (the innermost layer of the epidermis). They are found mostly in areas where sensory perception is acute, such as the fingertips.
microcephalyAbnormal smallness of the head; a congenital abnormality
migraineModerate to severe, painful headache that may occur with symptoms like nausea, vomiting, fatigue and numbness.mī'grān
mindfulnessA psychological state of awareness.
MSmultiple sclerosis
multiple sclerosisAn immune-mediated process in which the immune system attacks the myelin sheath that surrounds nerve fibers.
myel/ospinal cord, bone marrow
myelinA white fatty material that encloses certain axons and nerve fibers acting as an electrical insulator.
myelitisAn inflammation of the spinal cord.mi″ĕ-li´tis
myelographyA procedure that uses dye with x-rays or CT scans to assess the spinal cord,mi″ĕ-log´rah-fe
narc/osleep, numbness, stupor
narcolepsyA chronic brain disorder that involves poor control of sleep-wake cycles.nahr´ko-lep″se
negativismBehavior marked by extreme skepticism and persistent resistance to external advice.
neocortexThe largest portion of the cerebral cortex, the outer surface of the cerebrum, responsible for spatial reasoning, thought, language, memory and sensory perception.
nerveA cordlike structure of the body, comprising a collection of conducting fibers that convey impulses between a part of the central nervous system and another body region.
nerve blockInterruption of neural conduction in peripheral nerves or nerve trunks by the injection of a local anesthetic agent.
neural conductionThe propagation of the nerve impulse along the nerve away from the site of an excitation stimulus.
neuralgiaIntense pain that occurs along the course of a peripheral or cranial nerve.
neurapraxiaA peripheral nerve injury marked by a temporary loss of conduction of impulses.
neurastheniaA mental disorder characterized by chronic fatigue and concomitant physiologic symptoms.
neuri-nerve, nervous system
neuritisA general term indicating inflammation of a nerve, often marked by pain, numbness or tingling, or paralysis.
neurocytomaA brain tumor of undifferentiated cells of nervous origin.
neurofibromaA moderately firm, benign, encapsulated tumor resulting from proliferation of Schwann cells and fibroblasts that includes portions of nerve fibers.
neurofibrosarcomaA malignant tumor that arises from small cutaneous nerves, is locally aggressive, and has a potential for metastasis.
neurogenesisFormation of neurons which involves the differentiation and division of stem cells in which one or both of the daughter cells become neurons.
neurogliaThe supportive tissue of the nervous system
neurologicalPertaining to the nervous system
neurologyA medical specialty concerned with the study of the structures, functions, and diseases of the nervous system.
neuromaA benign neoplasm composed of nerve cells and nerve fibers.
neuronThe basic cellular unit of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the nervous system.
neuroretinitisInflammation of the optic nerve and retina.
neurotransmittersChemical messengers that carry signals to other cells in the body.
neurotropicHaving an affinity for the nervous system or the growth of neural tissue.
NGFnerve growth factor
-noiamind, will
NTDneural tube defect
obsessive compulsive disorderAn anxiety disorder characterized by recurrent, unwanted obsessions and compulsions.
obtundTo blunt or deaden pain.
OCDobsessive-compulsive disorder
olfactory nerveThe first cranial nerve. The olfactory nerve conveys the sense of smell.
painAn unpleasant or distressing localized sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.
panicA state of extreme acute, intense anxiety and unreasoning fear.
panic attackFear response that is out of proportion for the situation.
paranoiaOverly suspicious behavior.
paranoid behaviorBehavior exhibited by individuals who are overly suspicious, but without the symptoms characteristic of paranoid personality disorder or schizophrenia.
paranoid disordersChronic mental disorders in which there has been an insidious development of a permanent and unshakeable delusional system, but with clear and orderly thinking. Emotional responses and behavior are consistent with the delusional state.
-paresisweakness, slight paralysis
paresthesiaA sensation of tingling or numbness, skin crawling, or itching without apparent cause.par″es-the´zhah
parietal lobeUpper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the occipital lobe, and superior to the temporal lobes.
Parkinson diseaseA progressive disease of the nervous system that affects movement.
PDParkinson disease
peripheral neuropathyDysfunction of peripheral nerves which can impair movement, sensation and organ function. noo͡-rop´ah-the
phantom limbPhantom sensations that occur following the complete or partial loss of a limb.
phob/ofear, adversion
-phobiaabnormal fear
PNIperipheral nerve injury
PNSperipheral nervous system
polyneuropathyA disease of multiple peripheral nerves simultaneously.
ponsThe front part of the hindbrain that lies between the medulla and the midbrain ventral to the cerebellum, serving as a relay station for neural pathways.
post-traumatic stress disorderA disorder that develops in people who have experienced a terrifying event.
-praxiato perform, action
PTSDpost traumatic stress disorder
pudendal nerveA nerve which originates in the sacral spinal cord (S2 to S4) and innervates the perineum, the external genitalia, the external anal sphincter and the external urethral sphincter. Can be damaged in childbirth.
radial nerveA major nerve of the upper extremity, originating in the lower cervical and upper thoracic spinal cord, traveling via the posterior cord of the brachial plexus, and supplying motor innervation to extensor muscles of the arm and cutaneous sensory fibers to extensor regions of the arm and hand.
radicul/onerve root
radiculopathyDisease involving a spinal nerve root.
reflexA quick, involuntary movement or exercise of function, in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
reflex arcThe neural path of a reflex.
REMrapid eye movement
rem sleepA stage of sleep characterized by rapid eye movements and low voltage fast pattern EEG. It is usually associated with dreaming.
Reye syndromeAn acquired encephalopathy of young children that follows an acute febrile illness, usually influenza or varicella infection.
RINDreversible ischemic neurologic deficit
SADseasonal affective disorder
schizophreniaA chronic, severe mental illness that interferes with the ability to think, manage emotions, make decisions and relate to others.skit″so-fren´e-ah
sciatic nerveA nerve which originates in the lumbar and sacral spinal cord and supplies motor and sensory innervation to the lower extremity. The sciatic nerve is the largest nerve in the body.
sciaticaPain radiating along the sciatic nerve from the lower back down the´ĭ-kah
seizureA sudden surge of the brain’s electrical activity affecting movement and awareness for a short´zhur
sensationA perception produced by afferent nerve impulses conveyed to the sensorium.
sleepPhysiologic state of rest, relative unconsciousness and inaction of voluntary muscles.
smellThe ability to detect scents or odors, such as the function of olfactory receptor neurons.
spinal cordThe section of the central nervous system enclosed in the vertebral column.
spinal nervesThe 31 paired peripheral nerves formed by the union of the dorsal and ventral spinal roots from each spinal cord segment. The spinal nerve plexuses and the spinal roots are also included.
spinal punctureTapping fluid from the subarachnoid space in the lumbar region, usually between the third and fourth lumbar vertebrae.
spinal stenosisNarrowing of the spinal canal.
stressThe unfavorable effect of environmental factors on the physiological functions.
superegoThe component of the personality associated with ethics, standards, and self-criticism.
sural nerveA branch of the tibial nerve which supplies sensory innervation to parts of the lower leg and foot.
synaps/opoint of contact
synapseThe junctional area between two connected nerves or between a nerve and the effector organ.
syring/otube, pipe, fistula
-taxiaordering, arrangement
tectospinalDenoting nerve fibers passing from the mesencephalic tectum to the spinal cord.
telencephalonThe anterior subdivision of the prosencephalon which develops into the olfactory bulbs, cerebral cortex and basal ganglia.
temporal lobeOne of the main divisions of the cerebral cortex in each hemisphere of the brain, responsible for auditory, olfactory, and semantic processing.
TENStranscutaneous electrical nerve stimulation
tephr/ogray, ash-colored
tetanusAn acute, potentially fatal infection of the central nervous system caused by a powerful protein toxin produced by Clostridium tetani. Tetanus usually occurs after an acute injury, such as a puncture wound or laceration. Also called lockjaw.
thalamusPaired bodies containing mostly gray matter and forming part of the lateral wall of the third ventricle of the brain.
thec-case, sheath
thermoalgesiaAbnormal pain felt when part of the body is warmed.
thinkingThe act of reasoning. Cognition.
-thymiastate of mind
TIAtransient ischemic attack
titubationWalking with a staggering or stumbling gait.
tourette syndromeA neuropsychological disorder appearing in childhood, marked by multiple motor and vocal tics occurring multiple times daily over a period of more than one year.
tractotomySurgical incision of a nerve tract, usually to relieve pain.
tranceA sleeplike state of altered consciousness and diminution of motor activity,
tranquillizerA drug that reduces stress without diminishing mental clarity.
transferenceThe unconscious transfer to others of feelings and attitudes which were originally associated with important figures in one's early life.
trichotillomaniaCompulsion to pull out one's hair.
trigeminalPertaining to the fifth cranial nerve.
trigeminal neuralgiaAn inflammation of the trigeminal nerve causing extreme pain and muscle spasms in the face.trī-jem'i-năl nūr-al'jē-ă
unconsciousnessAbnormal loss of awareness of self and environment and lack of responsiveness to sensory stimuli.
vag/ovagus nerve
vagus nerveThe tenth cranial nerve.
white matterThe region of central nervous system that appears lighter in color than the other type, gray matter. it mainly consists of myelinated nerve fibers and contains few neuronal cell bodies or dendrites.