This glossary seeks to provide explanations for frequently used neurological terms
This glossary seeks to provide explanations for frequently used neurological terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
| A |
| Acetylcholine | A classical neurotransmitter found in the basal ganglia and throughout the body.An imbalance between the neurotransmitters acetylcholine and dopamine is associated with some of the symptoms of Parkinson disease (PD) for example, tremor and rigidity |
| Acetylcholinesterase | An enzyme that helps degrade the nerve transmitter substance "acetylcholine". Acetylcholinesterase is normally found at the point at which two nerves communicate |
| Action tremor | Involuntary movement of a limb after initiation of action |
| Acute Disseminated Encephalomyelitis (ADEM) | Acute, classically monophasic demyelinative disease of the CNS that may follow a viral syndrome or vaccination or no identifiable predisposing cause |
| Adrenoleukodystrophy | Progressive degeneration of the adrenal gland (adrenal atrophy) ie.adrenoleukodystrophy an inherited X-linked genetic trait |
| Agonisa | Inability to recognize and interpret objects, people, sounds, or smells despite intact primary sense organs (e.g., inability to identify a sound despite intact hearing); typically results from damage to the occipital or parietal lobe |
| Agonist | A chemical or drug that mimics the action of a neurotransmitter by stimulating the target site or receptor |
| Akinesia | A sharp decline in motor performance with complete loss of the ability to initiate voluntary movement and a loss of automatic movements,such as blinking |
| Alzheimer’s disease(AD) | A form of neurodegenerative disease resulting in progressive mental deterioration with disorientation, memory disturbance and confusion. Alzheimer's leads to progressive dementia, often accompanied by dysphasia and/or dyspraxia. The condition may also give rise ultimately to spastic weakness and paralysis of the limbs, epilepsy and other variable neurological signs. |
| Amantadine | Initially developed as an antiviral agent, this drug improves mild tremor, rigidity, and bradykinesia in some patients with PD. The exact mechanism of action is unclear; however, it seems to increase release of dopamine from the remaining cells of the substantia nigra |
| Amitriptyline | Amitriptyline hydrochloride is an antidepressant drug.It affects serotonin and noradrenaline reuptake.Used to treat depression in all stages of life. |
| Amyloid | An abnormal substance deposited between and within cells.Amyloid stains with the Congo Red stain.In Alzheimer's disease amyloid is abnormally deposited in neuritic plaques and in small blood vessels |
| Amyloid plaque | A characteristic pathological finding in the brains of Alzheimer’s disease patients consisting of aggregations of beta-amyloid protein |
| Amyloid Precursor Protein(APP) | A protein of uncertain function that is normally found in the brain. In Alzheimer's disease, APP is abnormally degraded resulting in the formation of amyloid |
| Amyotrophic Lateral Sclerosis (ALS) | A chronic,progressive disease marked by gradual degeneration of the nerve cells in the central nervous system that control voluntary muscle movement.The disorder causes muscle weakness and atrophy; symptoms commonly appear in middle to late adulthood,with death in two to five years.The cause is unknown, and there is no known cure. Also called Lou Gehrig's Disease,or Motor Neuron Disease.Literally,amyotrophic lateral sclerosis means without muscle nourishment,side (of spinal cord) hardening. |
| Androgen receptor(AR) | Receptors that have binding sites for the steroid androgen.Androgen receptors are altered in people with spinobulbar muscular atrophy(SBMA). |
| Antagonist | A drug that binds to a cellular receptor and prevents its activation by the natural ligands and does not by itself elicit any biological response |
| Anti-anxiety drug | Also called anxiolytics, this drug help manage a patient who has anxiety |
| Anticholinergic agents | Drugs, for example, procyclidine, that inhibit the actions of acetylcholine. Anticholinergic agents tend to have a limited impact on the symptoms of PD and cause a number of debilitating side-effects, such as dry mouth, blurred vision, confusion, and urinary retention |
| Anticholinesterase | A class of drugs frequently prescribed to patients with Alzheimer’s disease, which have some modest positive effects for some patients |
| Antidepressants | An anti-agitation drug to manage behavioral problems of a patient who suffers from depression |
| Antihistamines | The major effect of antihistamines is to inhibit the actions of histamine released in the body during an allergic reaction. In addition, antihistamines have anticholinergic properties that may be beneficial in the treatment of tremor in PD |
| Anti-inflammatory drugs | A class of drugs including aspirin,ibuprofen |
| Antioxidant | A molecule that is capable of reacting with free radicals and neutralizing them. |
| Anti-psychotic drug | Also called neuroleptics,this type of drug is used to help manage behavioral problems for a patient with a serious mental disorder |
| Aphasia | A speech problem that sometimes occurs to patients with Alzheimer’s disease or other cognitive illnesses |
| Apolipoprotein E(apoE) | A protein whose main function is to transport cholesterol. The gene for apoE is on chromosome 19. There are three forms of apoE: E2, E3, E4. E4 is associated with about 60% of late-onset Alzheimer’s disease and is considered a risk factor for Alzheimer’s disease |
| Apomorphine | A dopamine agonist given as a continuous subcutaneous infusion or as a subcutaneous injection. Apomorphine is used to alleviate the symptoms of severe PD that is responding poorly to levodopa. It is of particular benefit in patients with PD that experience ‘off’-times that last more than 30 minutes as it reverses symptoms within 10-15 minutes |
| Apraxia | Impaired planning/sequencing of movement that is not due to weakness, incoordination, or sensory loss. Although the movements cannot be performed for a specific situation, they may be performed under other circumstances (e.g., inability to lift feet off the floor when attempting to walk but preserved ability to perform bicycling movements of the legs while lying in bed). Results from dissociation of parts of the cerebrum and is often associated with parietal lobe lesions |
| Aricept | An anticholinesterase drug whose generic name is donepezil |
| Ataxia | Loss of balance |
| Atrophy | The progressive loss of muscle mass, or wasting, caused by reduction in the size or number of muscle cells. It is one of the later symptoms of ALS.Also shrinking of tissue,in Alzheimer’s disease the brain tissue usually is found to be atrophied |
| Autopsy | Examination of a body organ and tissue after death. Autopsy is often performed (upon request) in order to confirm diagnosis of Alzheimer’s disease |
| B |
| Basal ganglia | Groups of cells in the grey matter of each half of the brain which coordinate automatic movements.It comprises various specialised groups of cells,or nuclei,such as the globus pallidus and the substantia nigra |
| Basal ganglion | Singular form of basal ganglia. |
| Batten disease | A fatal,inherited disorder of the nervous system that begins in childhood;the most common form of a group of disorders called neuronal ceroid lipofuscinoses (NCLs).Early symptoms usually appear between the ages of 5 and 10 in the form of vision problems,seizures,personality and behavior changes,slow learning,clumsiness,or stumbling. Eventually, affected children suffer mental impairment, worsening seizures and progressive loss of sight and motor skills.Batten disease is often fatal by the late teens or twenties. |
| Battenin | The key protein involved in Batten disease. |
| Bells palsy | Cranial neuritis affecting the facial nerve thought to be due to reactivation of the herpes simplex virus; results in lower motor neuron facial weakness, hyperacusis, taste disturbance, and impaired lacrimation |
| Benserazide | The decarboxylase inhibitor that is co-administered with levodopa in Madopar® |
| Beta amyloid | An amyloid derived from a larger precursor protein and is a component of the neurofibrillary tangles and plaques characteristic of Alzheimer's disease |
| Beta-amyloid fibrils | A group primarily composed of proteins that lay flatly upon one another like sheets of paper. These are responsible for the amyloid plaques seen in Alzheimer's disease. Also known as simply amyloid fibrils. |
| Beta-amyloid plaques | Thick deposits of proteins in the brain that are believed to play a role in nerve cell degeneration in Alzheimer's disease. Also known as simply amyloid plaques. |
| Beta-secretase | An enzyme that catalyses the splitting of interior peptide bonds in a protein.Beta-secretase acts by trimming off a protein protruding from a brain cell. This small snip is thought to be the first step in the buildup of microscopic balls of debris known as amyloid that are toxic to brain cells. |
| Biopsy | A medical test to remove cells or tissue from a body to test them for a disease condition.The tissue can either be looked at under a microscope or analyzed using chemical tests.Biopsies are usually taken when the cause or extent of a disease is uncertain. |
| Blepharospasm | Excessive involuntary contraction of the orbicularis oculi sometimes resulting in functional blindness; a focal dystonia |
| Bradykinesia | A term used to describe slowness of motion and delayed initiation of movement, which is common in early stages of PD. Bradykinesia eventually progresses to akinesia |
| Bradyphrenia | Slowness of thought processes. |
| Brain | One of the two components of the central nervous system,the brain is the center of thought and emotion.It is responsible for the coordination and control of bodily activities and the interpretation of information from the senses (sight, hearing, smell, etc.).The other component of the central nervous system is the spinal cord. |
| Brain attack | Another term for stroke. |
| Brain stem | The portion of the brain closest to the spinal cord.It consists of the medulla,pons and midbrain and controls many of the involuntary functions that keep us alive. |
| Bromocriptine | One of the class of drugs known as dopamine agonists which are used to treat PD when levodopa alone is ineffective |
| Bulbar muscles | The muscles that control the speech,chewing and swallowing. |
| Bulbar region | An area of the brain composed of the cerebellum, medulla and pons.(Basically,the bulbar region is made up of the brain stem minus the midbrain and plus the cerebellum).The bulbar region is responsible for many involuntary functions that keep us alive. |
| C |
| Carbidopa | The decarboxylase inhibitor that is co-administered with levodopa in Sinemet® |
| Cataplexy | sudden loss of postural tone, often triggered by an emotional stimulus and resulting in falls to the floor; seen in narcolepsy |
| Catechol-O-methyl transferase(COMT) | One of the two main enzymes,the other is decarboxylase,responsible for the metabolism of levodopa in the blood and brain.COMT converts levodopa to 3-O-methyldopa |
| Cavernoma (cavernous malformation) | Vascular malformations composed primarily of large venous channels without a clear-cut arterial component |
| Celecoxib | An anti-inflammatory drug thought to reduce Alzheimer's risk in persons with a family history of dementia. |
| Central nervous system (CNS) | The part of the human nervous system consisting of the brain and the spinal cord. |
| Cerebral atrophy | The shrinking of the brain or brain cells |
| Cerebellar cortex | The outermost portion of the cerebellum |
| Cerebellum | Major region of the brain concerned with coordinating movements.The cerebellum is where learned movements are stored. |
| Cerebral cortex | The part of the brain that is visible from the outside.The cerebral cortex is the outermost layer and consists of a collection of nerve cell bodies. |
| Cerebellar dysfunction | An abnormality where people experience problems in walking, balance, and accurate hand and arm movement |
| Cerebrospinal fluid | The fluid surrounding the brain,contains substances that when analyzed can help in the diagnosis of Alzheimer’s disease.Collected by lumbar puncture. |
| Cerebral hemisphere | Symmetrical half of the cerebrum as separated by the sagittal sulcus and containing the cerebral cortex, basal ganglia, hippocampus, and amygdala |
| Cholinesterase inhibitors | Class of drugs known to delay the breakdown of acetylcholine. |
| Chorea | A type of dyskinesia characterised by rapid dance-like movements |
| Choroid plexus | Intraventricular structure that secretes cerebrospinal fluid |
| Cockayne Syndrome | A rare,autosomal recessive disorder characterized by growth failure, impaired development of the nervous system, abnormal sensitivity to sunlight (photosensitivity),and premature aging |
| Cognition | Brain functions involving,thinking,remembering,learning,reasoning and planning. |
| Cognitive symptoms | Dysfunction of cognition,in Alzheimer’s disease patients these are the defining early symptoms such as loss of memory,confusion and aphasias. |
| Computed tomography (CT) scan (pronounced "cat scan") | A type of X-ray that can give a health care professional two and three dimensional views of an internal organ or bodily tissues.CT scans of the brain are sometimes used to support the diagnosis for neurodegenerative diseases. |
| COMT inhibitors | A new class of drugs, for example, tolcapone and entacapone,that block COMT resulting in increased delivery of levodopa to the brain |
| Corpus striatum | Also known as the striatum,it is the largest part of the basal ganglia.This area receives information about the position and movement of the body from several different parts of the brain and transmits it to the substantia nigra.The globus pallidus forms part of the corpus striatum |
| Creutzfeldt-Jakob disease (CJD) | An infectious neurological disease that is a very rare form of encephalopathy thought to be caused by a virus called a prions.The disease occurs primarily in adults |
| Cortex | The outer layer of the cerebrum,densely packed with nerve cells. |
| Corticobasal degeneration | Progressive neurological disorder characterized by nerve cell loss in the cerebral cortex and basal ganglia and producing parkinsonism, dementia, visual-spatial impairment, alien hand syndrome, apraxia, and myoclonus |
| Creutzfeldt-Jakob disease | Fatal prion disease characterized by spongiform changes in the brain, progressive dementia, psychiatric changes, and myoclonus; form of spongiform encephalopathy |
| Cyclooxygenase(COX) | An enzyme that plays a pivotal role in the synthesis of prostaglandins. |
| D |
| Decarboxylase | An enzyme in the blood and brain that metabolizes levodopa to dopamine |
| Decarboxylase inhibitors(DCI) | Compounds, for example, carbidopa and benserazide, that prevent the peripheral conversion of levodopa to dopamine by decarboxylase. DCI increases the fraction of administered levodopa crossing the blood-brain barrier from 1% to 5-10%, resulting in a 70% reduction in levodopa dose required for symptom control. It has become common practice to co-administer a DCI with levodopa, for example, with carbidopa in Sinemet® and with benserazide in Madopar® |
| Delusion | A misperception of reality,patients with an altered mental status can suffer from delusions |
| Dementia | A disorder where brain cells die more quickly than in ordinary ageing, resulting in memory loss and confusion. Although affecting different cells to those affected in PD, it is experienced by some, especially elderly, patients with PD |
| Demyelination | Destruction or loss of the myelin sheath surrounding axons; results in impaired nerve impulse conduction |
| Diagnosis | The determination of the nature of a disease.(Eg) In the case of Alzheimer’s disease a definite diagnosis is only possible after an autopsy.However,health care professionals often speak of a diagnosis of probable AD when they think there is a high likelihood that the post-mortem findings will show Alzheimer’s disease. |
| Diffuse Lewy body disease (Lewy body dementia) | Form of dementia associated with fluctuating alertness, recurrent visual hallucinations, and parkinsonism and defined pathologically by cortical (as well as nigral) Lewy bodies |
| Disorientation | A cognitive disability in which the senses of time,direction and recognition become difficult to distinguish. |
| Disorientation | A cognitive disability in which the senses of time,direction and recognition become difficult to distinguish. |
| Donepezil | A drug currently approved in preventing the development of Alzheimer's in people diagnosed with mild cognitive impairment |
| Dopa decarboxylase | An enzyme present in the body that converts levodopa to dopamine. |
| Dopamine | Dopamine is a neurotransmitter formed in the substantia nigra and transmitted, by the nigrostriatal fibres, to the striatum. A decrease in the number of dopamine-producing cells in PD results in impaired communication between the substantia nigra and the striatum. Dopamine deficiency is a causative factor of PD and is associated with bradykinesia, tremor, and rigidity. Many of the drugs used in the treatment of PD alleviate symptoms by either replenishing dopamine e.g. levodopa or by mimicking the effects of dopamine |
| Dopamine agonists | Drugs (for example,lisuride,bromocriptine,cabergoline,pergolide and ropinirole) that stimulate dopamine receptors directly.They are often used in conjunction with levodopa to supplement its effect. They have a number of known side-effects, including nausea,vomiting, and sometimes severe psychiatric reactions – including hallucinations |
| Dyskinesia | The most common and disruptive side-effect of PD therapy,dyskinesia is an involuntary movement that can accompany peak doses of levodopa.Dystonia,athetosis and chorea are specific types of dyskinesis |
| Dysphagia | Difficulty in swallowing. |
| Dystonia | Involuntary spasms of muscle contraction that cause abnormal movements and postures. The dystonia that occurs most frequently in PD is in the foot and is a characteristic of PD |
| E |
| Early-onset Alzheimer’s disease | A type of Alzheimer’s disease in which individuals are diagnosed with AD before the age of 65.Approximately 1% to 10% of AD patients have early-onset.Early-onset AD is associated with mutations in genes located on chromosomes 1,14 and 21 |
| Electrodiagnostic tests | Studies including electromyography (EMG) and nerve conduction velocity( NCV),that evaluate and diagnose disorders of the muscles and motor neurons.Electrodes are inserted into the muscle,or placed on the skin overlying a muscle or muscle group,and electrical activity and muscle response are recorded |
| Electroencephalogram(EEG) | A method of recording the brain's continuous electrical activity by means of electrodes attached to the scalp |
| Electroencephalography | Technique that records and analyzes the electrical activity of the brain |
| Embolus | A "wandering" blood clot |
| Empty sella | Downward displacement and compression of the pituitary gland by cerebrospinal fluid filling the sella turcica; primary empty sella syndrome occurs when a small defect in the diaphragma sellae increases pressure in the sella and compresses the pituitary; secondary empty sella syndrome occurs when the sella is empty because the pituitary has shrunken following injury, surgery, or radiation |
| Encephalitis | An infection or inflammation of the brain tissue |
| Encephalopathy | Literally, "brain suffering"; diffuse brain dysfunction that may be caused by toxins, infection, metabolic or mitochondrial disease, tumor or increased intracranial pressure, trauma, or lack of blood flow or oxygen to the brain |
| Enzymes | Complex proteins that are produced by living cells and bring about specific biochemical reactions at body temperature |
| Epilepsy | Disorder caused by the sudden overactivity of brain cells and characterized by repetitive attacks of a diverse nature |
| Epilepsy syndrome | Disorder defined by seizure type, clinical and EEG findings, age of onset, family history, response to therapy, and prognosis |
| F |
| Familial Amyotrophic Lateral Sclerosis | A progressive neurological disease that affects more than one member of the same family.This type of ALS accounts for a very small number of people with ALS in the United States(5 to 10 percent) |
| Festination | Festination is identified by short,shuffling steps and is a characteristic gait disturbance of Parkinsons Disease |
| Fluctuator/non-fluctuator | A simple classification of patients with Parkinsons Disease.Categories are based on motor fluctuation and the reponse to levodopa/DCI therapy.The de novo group are newly diagnosed, have no functional symptoms, have had no prior treatment but have obvious symptoms.Non-fluctuators have some functional disability that is adequately controlled by treatment, but no motor fluctuation.Fluctuators have severe functional disability that is poorly controlled by therapy,and suffer significant motor fluctuation |
| Foramen magnum | Large opening at the base of the skull through which the spinal cord and vertebral arteries pass from the vertebral cavity into the cranial cavity |
| Foramen of Magendie | Midline exit of CSF from the fourth ventricle into the subarachnoid space |
| Foramen of Monro | Permits communication of the third ventricle with each of the lateral ventricles on anterolateral aspect of the third ventricle |
| Friedreichs ataxia | A genetic,progressive,neurologic movement disorder that typically becomes apparent before adolescence |
| Frontotemporal dementia | Group of dementing illnesses in which disordered behavior (e.g., disinhibition) or language (e.g., aphasia) are disproportionately impaired in relation to memory; includes Pick’s disease and corticobasal degeneration |
| G |
| Gait | A person’s manner of walking. People in the later stages of Alzheimer’s often have "reduced gait," meaning they may lose the ability to lift their feet as they walk |
| Gamma secretase | An enzyme partly responsible for plaque buildup in the brain characteristic of Alzheimer’s |
| Ganglion | A cluster of nerve cell bodies |
| Gene | The basic unit of heredity;a section of DNA coding for a particular trait |
| Genetic susceptibility | The state of being more likely than the average person to develop a disease as a result of genetics |
| Gerstmann syndrome | A neurological disorder that includes a writing disability (agraphia or dysgraphia), a lack of understanding of the rules for calculation or arithmetic (acalculia or dyscalculia), an inability to distinguish right from left, and an inability to identify fingers (finger agnosia) that is due to a lesion of the angular gyrus of the dominant parietal lobe |
| Gingko biloba | A natural product as a potential treatment for Alzheimers and vascular dementia |
| Glia | Supporting tissue that is intermingled with the essential elements of nervous tissue especially in the brain and spinal cord |
| Glutamate | A primary excitatory neurotransmitter in the human CNS.Over-stimulation of these receptors is thought to trigger the neuronal damage associated with a wide variety of neurological insults and diseases,including amyotrophic lateral sclerosis(ALS),lathyrisms and Alzheimer's disease |
| Gray matter | The darker-colored tissues of the central nervous system.In the brain,the gray matter includes the cerebral cortex,the thalamus,the basal ganglia and the outer layers of the cerebellum |
| Guillain-Barre syndrome (acute inflammatory demyelinating polyneuropathy) | Acute, ascending, and progressive neuropathy believed to result from an autoimmune response triggered by an antecedent illness or various medical conditions and characterized by weakness, paresthesias, hyporeflexia, and labile autonomic dysfunction |
| H |
| Hippocampus | An area buried deep in the forebrain that helps regulate emotion and memory |
| Holoprosencephaly | Failure of cleavage at the rostral end of the notochord resulting in midline fusion of the frontal lobes, midline facial abnormalities, and often hydrocephalus and heterotopias |
| Huntingtons disease | A progressive,degenerative disease that causes nerve cells in brain to waste away to cause uncontrolled movements and mental deterioration |
| Hydranencephaly | Birth defect in which the majority of the cerebral hemispheres and striatum are absent and replaced by sacs filled with cerebrospinal fluid; considered to be an extreme form of porencephaly |
| I |
| Ibuprofen | A non-steroidal,anti-inflammatory drug used to relieve pain and fever |
| Impairment | Problem in body function or structure such as a significant deviation or loss (e.g., weakness = impairment in the muscles' capability to produce force) |
| Incidence | The occurrence of new cases of a condition.The incidence rate describes the frequency with which cases are identified.Incidence is commonly measured in new cases per 1,000 (or 100,000) of population at risk, per year |
| Indomethacin | A non-steroidal,anti-inflammatory drug,analgesic, used especially in treating arthritis |
| Infarction | Permanent tissue damage and death of all cellular elements (neurons, glia, vessels) due to prolonged or severe ischemia |
| Inflammation | A basic way in which the body reacts to infection, irritation or other injury, the key feature being redness, warmth, swelling and pain Inflammation is now recognized as a type of nonspecific immune response |
| Inflammatory disease | Diseases that are characterized by activation of the immune system to abnormal levels that lead to disease |
| Intention tremor | Tremor whose amplitude increases as the affected body part (typically a finger) nears an intended target and that may the targeted object to be missed; typically results from damage to the cerebellum or its connections |
| Intrathecal | Injection into the innermost membrane surrounding the central nervous system. Usually done by lumbar puncture |
| Irradiate | To expose a structure or organism to radiation |
| Ischemia | Impairment of tissue function due to a reduction in blood supply relative to metabolic demand |
| J |
| Joubert syndrome | A rare brain malformation characterized by the absence or underdevelopment of the cerebellar vermis - an area of the brain that controls balance and coordination |
| Juvenile ALS | ALS2 — also called autosomal recessive juvenile ALS type 3 — manifests around 12 years of age, advances slowly over many years, and takes an especially noticeable toll on the upper motor neurons. It affects a small number of families, mostly in Northern Africa and the Middle East |
| K |
| Kennedy disease | A rare,slowly progressive muscular disorder that affects males only and is inherited as an X-linked genetic trait |
| Korsakoff syndrome | Chronic phase of thiamine deficiency characterized by impairment in establishing new memories and retrieving previous memories, occurring most commonly in alcoholics |
| Krabbe disease | An inborn neurodegenerative disorder of infancy due to the accumulation of galactocerebroside in the tissues.This is a result of a primary deficiency of galactocerebrosidase |
| Kuru | Fatal prion disease restricted to the Fore tribe in the highlands of New Guinea as a result of cannibalistic funeral practices; form of spongiform encephalopathy |
| L |
| Lambert-Eaton Myasthenic syndrome | Autoimmune disorder of neuromuscular transmission characterized by antibodies directed against the voltage-gated calcium channels on the presynaptic motor nerve terminal leading to impaired release of acetylcholine and causing proximal muscle weakness |
| Leukodystrophy | Metabolic demyelinative disease |
| Levodopa | A precursor of dopamine which is converted to dopamine in the brain.Levodopa is currently the treatment of choice for PD and is a constituent of Sinemet® and Madopar® |
| Lewy bodies | Microscopic abnormalities seen,at autopsy,in the brains of patients with PD |
| Lissencephaly (agyria) | Smooth brain (absence of secondary sulci) |
| Lower motor neuron | Nerve cells starting at the spinal cord or brain stem and ending at the muscle fibers.The loss of lower motor neurons leads to weakness,twitching of muscles (fasciculations) and loss of muscle bulk (atrophy) |
| M |
| Macrocephaly | Head circumference that is more than 2 standard deviations above the mean for age, sex, race, and gestation |
| Memantine | A part of the brainstem that helps regulate respiration and other behaviors |
| Memantine | A drug approved by the FDA in October 2003 for the treatment of moderate to severe Alzheimer's disease, generic for Namenda |
| Meninges | Three distinct connective tissue membranes (from outer to inner: dura, arachnoid, and pia mater) that enclose and protect the central nervous system |
| Metachromatic leukodystrophy | Autosomal recessive disease associated with large confluent areas of discolored gelatinous white matter caused by deficiency of the enzyme arylsulfatase A, which is necessary for the degradation of sulfatide, a myelin constituent |
| Monoamine oxidase B (MAO-B) | An enzyme that metabolizes dopamine |
| Monoamine oxidase inhibitors(MAO-I) | Drugs (e.g. selegiline) that block monoamine oxidases resulting in prolonged availability of dopamine in the brain |
| Motor control | A patient’s ability to control movement |
| Motor fluctuation | Variations in motor control |
| Motor neurons | Nerve cells that direct movement |
| MRI | MRI stands for magnetic resonance imaging.A special radiology technique designed to image internal structures of the body using magnetism, radio waves,and a computer to produce the images of body structures |
| Multi-infarct dementia | Form of vascular dementia involving deterioration of mental function caused by infarcts in multiple brain regions |
| Multiple sclerosis (MS) | A chronic degenerative disease of the central nervous system in which gradual destruction of myelin occurs in patches throughout the brain or spinal cord (or both), interfering with the nerve pathways and causing muscular weakness, loss of coordination and speech and visual disturbances |
| Muscle atrophy | Loss of muscle fiber volume characterized by a visible decrease in muscle size.This occurs because muscles no longer receive impulses or signals from nerve cells |
| Muscular dystrophy | The name given to a group of diseases that are,for the most part,genetically determined and which cause gradual wasting of muscle with accompanying weakness and deformity |
| Myelin | Fatty substance forming an insulating sheath around axons to increase the velocity of action potential conduction; produced by oligodendrocytes in the CNS and by Schwann cells in the PNS |
| N |
| Narcolepsy | Sleep disorder characterized by excessive daytime sleepiness and dysregulated REM sleep |
| Neuritic plaques | Abnormal collections of nerve processes surrounding a central core of amyloid.Neuritic plaques,together with neurofibrillary tangles, are the hallmarks of Alzheimer's disease. |
| Neurodegenerative | An abnormal deterioration of the nervous system |
| Neurofibrillary tangles | Abnormal bundles of filaments in nerve cells in the brain. These filaments contact on protein tau and are of the typical features of Alzheimer's disease. |
| Neuroleptics | A term that refers to the effects of antipsychotic drugs on a patient,especially on cognition and behavior |
| Neuroleptic malignant syndrome | Rare, but life-threatening, idiosyncratic reaction to antipsychotic drugs that is characterized by high fever, hypertension, severe rigidity, altered mental status, and autonomic dysfunction |
| Neuron | A specialised cell that transmits signals to different parts of the brain |
| Neuronal ceroid lipofuscinoses (NCLs) | A group of rare, inherited degenerative disorders of the nervous system; associated with the accumulation of an abnormal pigment in the brain called lipofuscin. These disorders can have severe diseases including blindness, mental retardation, and early death (eg)Batten Disease |
| Neuroprotective | The property of preventing damage and degeneration to nerve cells |
| Neuropsychiatrist | A specialist in the branch of medicine concerned with both neurology and psychiatry |
| Neuropsychological | Concerned with the integration of psychological observations on behavior and the mind with neurological observations on the brain and nervous system |
| Neuropsychologist | A psychologist who has completed special training in the neurobiological causes of brain disorders, and who specializes in diagnosing and treating these illnesses using a predominantly medical (as opposed to psychoanalytical) approach |
| Neurotransmitter | A chemical that is released from a neurone and transmits a message to either a nerve or a cell. Examples include dopamine and acetylcholine |
| NMDA receptor | A type of receptor that binds glutamate.It is selectively activated by the drug NMDA (N-methyl-D-aspartate) |
| Non-pharmacological | Various strategies aimed at managing problematic behaviors, including therapy, changes in the home or environment and the use of appropriate communication techniques |
| O |
| Olivopontocerebellar atrophy (OPCA) | Older term for a variant of multisystems atrophy characterized by preferential degeneration of the cerebellum and brainstem producing symmetric parkinsonism and ataxia, dysarthria, dysphagia, pyramidal signs, and often ocular motility disorders |
| Orthostatic hypotension | A decrease in blood pressure upon standing. In PD this may occur either spontaneously or as a result of drug treatment |
| Oxidative stress | Accumulation of destructive molecules called free radicals can lead to motor neuron death. Free radicals damage components of the cells' membranes, proteins or genetic material by "oxidizing" them - the same chemical reaction that causes iron to rust (eg)Some patients with familial ALS have mutations in the gene for superoxide dismutase type 1 (SOD1).SOD1 normally breaks down free radicals, but mutant SOD1 is unable to perform this function. These free radicals may be generated when the enzyme superoxide dismutase malfunctions (either because of a genetic mutation or because of the chemical environment of the nerve cells), or they may be generated as a result of glutamate excitotoxicity,or for some other reason |
| P |
| Palsy | Paralysis of a muscle or group of muscles |
| Paralysis | Loss of motor function in a body part |
| Parkinson’s disease | A progressive disease that is attributable to degenerative changes in cells of the basal ganglia. These result in a deficiency of the neurotransmitter dopamine and in turn, impaired control of movement |
| Parkinsonism | The name given to a group of disorders with similar features -- four primary symptoms (tremor, rigidity, postural instability, and bradykinesia) that are the result of the loss of dopamine-producing brain cells |
| Partial (focal) seizure | Seizure that starts in a single cortical region |
| PET | Positron emission tomography, a highly specialized imaging technique using short-lived radioactive substances. This technique produces three-dimensional colored images |
| Pharmacological | The properties and reactions of drugs especially with relation to their therapeutic value and medical toxicology |
| Pick’s disease | Form of frontotemporal dementia characterized by a slowly progressive deterioration of social skills and changes in personality in addition to impairment of intellect, memory, and language |
| Plaque | A localized abnormal patch on a body part or surface |
| Pramipexole | A new dopamine agonist |
| Presenilin 1 | A gene,when mutated, causes an abnormal presenilin 1 protein to be produced |
| Presenilin 2 | A gene,when mutated, causes an abnormal presenilin 2 protein to be produced |
| Primary lateral sclerosis (PLS) | A progressive neurological disease in which the upper motor nerve cells deteriorate.If the lower motor neurons are not affected within two years,the disease usually remains a purely upper motor disease |
| Prion | Proteinacious infectious agent responsible for various fatal brain diseases classified as spongiform encephalopathy |
| Progressive bulbar palsy (PBP) | A condition that begins with difficulties in speaking, chewing and swallowing due to lower motor nerve cell (neuron) deterioration.This disorder affects about 25 percent of all people with ALS |
| Progressive muscular atrophy (PMA) | A progressive neurological disease in which the lower motor nerve cells (neurons) deteriorate |
| Progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome) | Parkinson plus syndrome characterized by predominantly axial rigidity, akinesia, supranuclear ophthalmoplegia (impairment of voluntary vertical gaze—downward more than upward), and pseudobulbar palsy |
| Pseudobulbar palsy | A condition characterized by difficulties with speech, chewing and swallowing. These symptoms resemble those of bulbar palsy, but this condition is also characterized by spontaneous or unmotivated crying and laughing. |
| Q |
| Quadrigeminal bodies | Two pairs of elevations on the dorsal surface of the midbrain; includes the superior colliculi and inferior collicli |
| Quadriplegia (tetraplegia) | Paralysis of all four extremities |
| R |
| Receptor | A cell or group of cells that receive stimuli |
| Resting tremor | Shaking that occurs in a relaxed limb.It usually stops when a voluntary movement of the affected limb is made |
| Restless legs syndrome | Sleep disorder characterized by tingling, creepy-crawly, or aching sensation in the legs and sometimes arms as well as motor restlessness that tends to occur at rest (especially around the patient’s usual bedtime) and to be relieved temporarily by movement |
| Rigidity | Resistance to manipulation of a limb.Cogwheel rigidity,a characteristic of PD,occurs when rigidity is combined with tremor |
| Rilutek | The only FDA-approved drug available to treat ALS.It inhibits glutamate release,and prolongs life approximately three months.Riluzole is the generic name of Rilutek |
| S |
| Sclerosis | A hardening within the nervous system, especially of the brain and spinal cord, resulting from degeneration of nervous elements such as the myelin sheath. |
| Secretase | The enzyme involved in cutting amyloid into the shorter beta-amyloid form |
| Sedatives | Drugs that calm a patient down, easing agitation and permitting sleep. Sedatives generally work by modulating signals within the central nervous system |
| Seizure | Discrete event due to sudden, transient, excessive neuronal discharges in the brain |
| Selegiline | An irreversible monoamine oxidase B inhibitor.Selegiline helps conserve levels of dopamine in the brain by blocking the enzyme (MAO-B) responsible for dopamine degradation |
| Shaking palsy | The term originally employed by James Parkinson to describe the disorder now known as PD |
| Serotonin | An important neurochemical whose effects upon the human brain include mood elevation. Production of serotonin in the brain is increased by ingestion of the amino acid tryptophan (a chemical precursor to serotonin) |
| Side-effect | An additional activity of a drug that may produce detrimental or unwanted effects |
| Sinemet® | A formulation combining levodopa and carbidopa |
| Spasticity | Abnormal increase in muscle tone and reflexes, manifested as a velocity dependent spring-like resistance to moving or being moved; indicates an upper motor neuron lesion |
| Spinal muscular atrophy (SMA) | A hereditary neurological disease in which only the lower motor nerve cells are affected |
| Spinocerebellar ataxia | Group of hereditary neurodegenerative disorders caused by expansion of a CAG triplet repeat and characterized by progressive ataxia and variable other features such as neuropathy and hearing or visual loss |
| Spongiform encephalopathy | Progressive neurodegenerative disorder associated with various prion agents that produce spongy changes in the brain (e.g., Creutzfeldt-Jakob disease, kuru) |
| Striatal | Pertaining to the corpus striatum - one of the components of the basal ganglia |
| Striatonigral degeneration (SND) | Older term for a variant of multisystems atrophy characterized by degeneration of the striatum and the substantia nigra producing symmetric parkinsonism that does not respond to levodopa or dopamine agonists |
| Stroke | Also called a "brain attack" and happens when brain cells die because of inadequate blood flow. 20% of cases are a hemorrhage in the brain caused by a rupture or leakage from a blood vessel. 80% of cases are also know as a "schemic stroke", or the formation of a blood clot in a vessel supplying blood to the brain. |
| Substantia nigra | A region of the basal ganglia that is rich in dopamine-containing neurones.Its name,literally meaning black substance,comes from the black appearance seen post-mortem |
| Superoxide dismutase | An enzyme that destroys superoxide.One form of the enzyme contains manganese and another contains zinc.Superoxide is a highly reactive form of oxygen.For ALS, 20% of the total population of patients have mutations in the gene for copper/zinc superoxide dismutase type SOD1. SOD1 normally breaks down free radicals,but mutant SOD1 is unable to perform this function. |
| T |
| Tacrine | An anticholinesterase drug, also called Cognex |
| Tangles | Twisted fibers that build up inside the nerve cells |
| Tardive | Symptoms that develop slowly or appear long after inception, e.g., tardive dyskinesia occurring after chronic exposure to dopamine antagonists |
| Tau | A protein which channels chemical messages inside nerve cells |
| Tauopathies | Group of neurodegenerative diseases characterized predominantly by abnormalities of tau protein; includes frontotemporal dementia, progressive supranuclear palsy, corticobasal degeneration |
| Tethered cord | Attachment of the spinal cord to the vertebral column or subcutaneous tissues by a thickened filum terminale, fibrous band, diastematomyelia, dermal sinus tract, or lipoma resulting in a low-lying conus medullaris |
| Tolcapone | A COMT inhibitor, now available in many countries worldwide as Tasmar® |
| Tourette syndrome | Childhood onset movement disorder characterized by simple or complex tics and often associated with obsessions,compulsions, and attention deficit disorder |
| Transverse myelitis | Inflammatory disease involving both sides of the spinal cord in which motor and sensory deficits occur below the level of the lesion; occurs commonly in multiple sclerosis and various infectious and connective tissue disorders |
| Tremor | Involuntary shaking |
| U |
| Unilateral | Occurring on one side of the body |
| Upper motor neurons | Nerve cells (motor neurons)originating in the brain's motor cortex and running through the spinal cord |
| V |
| Vascular dementia | A common cause of memory loss in the elderly caused by multiple strokes disruption of blood flow to the brain leading to damaged brain tissue |
| Vasospasm | Blood vessel constriction in response to irritative stimuli |
| W |
| ‘Wearing off’ | A phenomenon characterized by a progressive shortening of ‘on’-time following a dose of levodopa |
| White matter | Nerve tissue that is paler in color than gray matter because it contains nerve fibers with large amounts of insulating material (myelin).The white matter does not contain nerve cells.In the brain,the white matter lies within the gray layer of the cerebral cortex |
| Williams Syndrome | A rare genetic disorder characterized by growth delays before and after birth (prenatal and postnatal growth retardation),short stature,varying levels of mental deficiency, and distinctive facial abnormalities that typically become more pronounced with age |
| X |
| No records found |
| Y |
| No records found |
| Z |
| Zellweger Syndrome | An inherited peroxisomal metabolic disorder.Peroxisomes are found in almost all body cells and are responsible for many important cell processes.Zellweger syndrome causes a defect in the peroxisomes,which affects the body severely |