Neurology

Special Topics
ALS - resources

Diseases & Conditions
Absence seizure
An absence seizure is the term for a type of seizure involving staring spells. This type of seizure is a brief (usually less than 15 seconds) disturbance of brain function due to abnormal electrical activity...

Tests
Acetylcholine receptor antibody
Acetylcholine receptor antibody is a protein found in the blood of many people with myasthenia gravis. The antibody affects the part of nerve cells that send signals from nerves to muscles. myasthenia gravis...

Diseases & Conditions
Acoustic neuroma
An acoustic neuroma is a slow-growing tumor of the nerve that connects the ear to the brain. This nerve is called the vestibular cochlear nerve. It is behind the ear, right under the brain. An acoustic...

Diseases & Conditions
Acute cerebellar ataxia
Acute cerebellar ataxia is sudden inability to coordinate muscle movement due to disease or injury to the cerebellum. This is the area in the brain that controls muscle movement. Ataxia means loss of muscle...

Diseases & Conditions
Acute flaccid myelitis
Acute flaccid myelitis is a rare condition that affects the nervous system. Inflammation of the gray matter in the spinal cord leads to muscle weakness and paralysis. Acute flaccid myelitis (AFM) is usually...

Special Topics
Aging changes in the nervous system

Diseases & Conditions
Alcoholic neuropathy
Alcoholic neuropathy is damage to the nerves that results from excessive drinking of alcohol.

Diseases & Conditions
Alzheimer disease
Dementia is a loss of brain function that occurs with certain diseases. Alzheimer disease (AD) is the most common form of dementia. It affects memory, thinking, and behavior. Dementia may also be referred...

In-depth Report
Alzheimer disease - InDepth
An in-depth report on the causes, diagnosis, and treatment of Alzheimer disease.

Diseases & Conditions
Amaurosis fugax
Amaurosis fugax is a temporary loss of vision in one or both eyes due to a lack of blood flow to the retina. The retina is the light-sensitive layer of tissue at the back of the eyeball. retina

Diseases & Conditions
Amyotrophic lateral sclerosis (ALS)
Amyotrophic lateral sclerosis, or ALS, is a disease of the nerve cells in the brain, brain stem and spinal cord that control voluntary muscle movement. ALS is also known as Lou Gehrig disease.

Diseases & Conditions
Aneurysm
An aneurysm is an abnormal widening or ballooning of a part of an artery due to weakness in the wall of the blood vessel.

Diseases & Conditions
Aneurysm in the brain
An aneurysm is a weak area in the wall of a blood vessel that causes the blood vessel to bulge or balloon out. When an aneurysm occurs in a blood vessel of the brain, it is called an intracranial aneurysm...

Symptoms
Anisocoria
Anisocoria is unequal pupil size. The pupil is the black part in the center of the eye. It gets larger in dim light and smaller in bright light.

Tests
Apgar score
Apgar is a quick test performed on a baby at 1 and 5 minutes after birth. The 1-minute score determines how well the baby tolerated the birthing process. The 5-minute score tells the health care provider...

Diseases & Conditions
Apoplexy
Apoplexy is bleeding into an organ or loss of blood flow to an organ. For example, Adrenal apoplexy -- bleeding into the adrenal glandsPituitary apoplexy -- bleeding into the pituitary gland Adrenal apoplexy...

Diseases & Conditions
Apraxia
Apraxia is a disorder of the brain and nervous system in which a person is unable to perform tasks or movements when asked, even though: The request or command is understoodThey are willing to perform the...

Diseases & Conditions
Autism spectrum disorder
Autism spectrum disorder (ASD) is a developmental disorder. It often appears in the first 2 to 3 years of life. ASD affects the brain's ability to develop normal social and communication skills.

Diseases & Conditions
Autism spectrum disorder - childhood disintegrative disorder
Childhood disintegrative disorder is a condition in which children develop normally through about age 3. Then, over a few months, they lose language, motor, social, and other skills that they already learned...

Diseases & Conditions
Autonomic dysreflexia
Autonomic dysreflexia is an abnormal, overreaction of the involuntary (autonomic) nervous system to stimulation. This reaction may include: Change in heart rateExcessive sweatingHigh blood pressureMuscle...

Diseases & Conditions
Autonomic neuropathy
Autonomic neuropathy is a group of symptoms that occur when there is damage to the nerves that manage normally automatic body functions. These functions include blood pressure, heart rate, sweating, bowel...

Diseases & Conditions
Axillary nerve dysfunction
Axillary nerve dysfunction is nerve damage that can lead to a loss of movement or sensation in the shoulder.

Tests
BAER - brainstem auditory evoked response
Brainstem auditory evoked response (BAER) is a test to measure the brain wave activity that occurs in response to clicks or certain tones.

Symptoms
Babinski reflex
Reflexes are responses that occur when the body receives a certain stimulus. The Babinski reflex occurs after the sole of the foot has been firmly stroked. The big toe then moves upward or toward the top...

Diseases & Conditions
Basal ganglia dysfunction
Basal ganglia dysfunction is a problem with the deep brain structures that help start and control movement.

Self-Care Instructions
Bathroom safety for adults
Older adult bathroom safety; Falls - bathroom safety

Diseases & Conditions
Becker muscular dystrophy
Becker muscular dystrophy is an inherited disorder that involves slowly worsening muscle weakness of the legs and pelvis. muscle weakness

Diseases & Conditions
Bell palsy
Bell palsy is a disorder of the nerve that controls movement of the muscles in the face. This nerve is called the facial or seventh cranial nerve. Damage to this nerve causes weakness or paralysis of these...

Diseases & Conditions
Benign positional vertigo
Benign positional vertigo is the most common type of vertigo. Vertigo is the feeling that you are spinning or that everything is spinning around you. It may occur when you move your head in a certain position...

Diseases & Conditions
Bilateral tonic-clonic seizure
Bilateral tonic-clonic seizure is a type of seizure that involves the entire body. It is also called grand mal seizure. The terms generalized seizure, convulsion, or epilepsy are most often associated with...

Diseases & Conditions
Brachial plexopathy
Brachial plexopathy is a form of peripheral neuropathy. It occurs when there is damage to the brachial plexus. This is a group of nerves that run from the lower neck through the upper shoulder area. These...

Special Topics
Brachial plexus
The brachial plexus is a group of nerves that run from the lower neck through the upper shoulder area. These nerves provide the shoulder, arm, forearm, and hand with movement and sensation.

Tests
Brain PET scan
A brain positron emission tomography (PET) scan is an imaging test of the brain. It uses a radioactive substance called a tracer to look for disease or injury in the brain. A PET scan shows how the brain...

Diseases & Conditions
Brain abscess
A brain abscess is a collection of pus, immune cells, and other material in the brain, caused by a bacterial or fungal infection.

Discharge Instructions
Brain aneurysm repair - discharge
Aneurysm repair - cerebral - discharge; Cerebral aneurysm repair - discharge; Coiling - discharge; Saccular aneurysm repair - discharge; Berry aneurysm repair - discharge; Fusiform aneurysm repair - discharge...

Diseases & Conditions
Brain herniation
Brain herniation is the shifting of the brain tissue from one space in the skull to another through various folds and openings.

Discharge Instructions
Brain injury - discharge
Head injury - discharge; Head trauma - discharge; Contusion - discharge; Shaken baby syndrome - discharge

Discharge Instructions
Brain surgery - discharge
Craniotomy - discharge; Neurosurgery - discharge; Craniectomy - discharge; Stereotactic craniotomy - discharge; Stereotactic brain biopsy - discharge; Endoscopic craniotomy - discharge

In-depth Report
Brain tumors - primary - InDepth
An in-depth report on the causes, diagnosis, and treatment of primary brain tumors.

Tests
CSF analysis
Cerebrospinal fluid (CSF) analysis is a group of laboratory tests that measure chemicals in the cerebrospinal fluid. CSF is a clear fluid that surrounds and protects the brain and spinal cord. The tests...

Tests
CSF cell count
A CSF cell count is a test to measure the number of red and white blood cells that are in cerebrospinal fluid (CSF). CSF is a clear fluid that is in the space around the spinal cord and brain.

Tests
CSF glucose test
A CSF glucose test measures the amount of sugar (glucose) in the cerebrospinal fluid (CSF). CSF is a clear fluid that flows in the space surrounding the spinal cord and brain.

Diseases & Conditions
CSF leak
A CSF leak is an escape of the fluid that surrounds the brain and spinal cord. This fluid is called the cerebrospinal fluid (CSF).

Tests
CSF myelin basic protein
CSF myelin basic protein is a test to measure the level of myelin basic protein (MBP) in the cerebrospinal fluid (CSF). myelin CSF is a clear liquid that surrounds the brain and spinal cord. MBP is found...

Tests
CSF oligoclonal banding
CSF oligoclonal banding is a test to look for inflammation-related proteins in the cerebrospinal fluid (CSF). CSF is the clear fluid that flows in the space around the spinal cord and brain. Oligoclonal...

Tests
CSF smear
A cerebrospinal fluid (CSF) smear is a laboratory test to look for bacteria, fungi, and viruses in the fluid that moves in the space around the spinal cord and brain. CSF protects the brain and spinal cord...

Tests
CSF total protein
CSF total protein is a test to determine the amount of protein in cerebrospinal fluid (CSF). CSF is a clear fluid that is in the space around the spinal cord and brain. protein

Tests
CSF-VDRL test
The CSF-VDRL test is used to help diagnose neurosyphilis. It looks for substances (proteins) called antibodies, which are sometimes produced by the body in reaction to the syphilis-causing bacteria. neurosyphilis...

Tests
CT angiography - head and neck
CT angiography (CTA) combines a CT scan with the injection of dye. CT stands for computed tomography. This technique is able to create pictures of the blood vessels in the head and neck.

Tests
Caloric stimulation
Caloric stimulation is a test that uses differences in temperature to diagnose damage to the acoustic nerve. This is the nerve that is involved in hearing and balance. The test also checks for damage to...

Self-Care Instructions
Caring for muscle spasticity or spasms
High muscle tone - care; Increased muscle tension - care; Upper motor neuron syndrome - care; Muscle stiffness - care

Diseases & Conditions
Carotid artery disease
Carotid artery disease causes the carotid arteries to become narrowed or blocked. The carotid arteries provide part of the main blood supply to your brain. They are located on each side of your neck. You...

Self-Care Instructions
Carotid artery stenosis - self-care
Carotid artery disease - self-care

Tests
Carotid duplex
Carotid duplex is an ultrasound test that shows how well blood is flowing through the carotid arteries. The carotid arteries are located in the neck. They supply blood directly to the brain. ultrasound

Special Topics
Central nervous system
The central nervous system is composed of the brain and spinal cord. Your brain and spinal cord serve as the main "processing center" for your entire nervous system. They control all the workings of your...

Diseases & Conditions
Cerebral amyloid angiopathy
Cerebral amyloid angiopathy (CAA) is a condition in which proteins called amyloid build up on the walls of the arteries in the brain. CAA causes bleeding into the brain (hemorrhagic stroke) and dementia...

Tests
Cerebral angiography
Cerebral angiography is a procedure that uses a special dye (contrast material) and x-rays to see how blood flows through the brain.

Diseases & Conditions
Cerebral arteriovenous malformation
A cerebral arteriovenous malformation (AVM) is an abnormal connection between the arteries and veins in the brain that usually forms before birth.

Diseases & Conditions
Cerebral hypoxia
Cerebral hypoxia occurs when there is not enough oxygen getting to the brain. The brain needs a constant supply of oxygen and nutrients to function. Cerebral hypoxia affects the largest parts of the brain...

Diseases & Conditions
Cerebral palsy
Cerebral palsy (CP) is a group of disorders that involve the brain. This affects nervous system functions, such as movement, learning, hearing, seeing, and thinking. There are several different types of...

Special Topics
Cerebral palsy - resources

Tests
Cerebrospinal fluid (CSF) collection
Cerebrospinal fluid (CSF) collection is a test to look at the fluid that surrounds the brain and spinal cord. CSF acts as a cushion, protecting the brain and spine from injury. The fluid is normally clear...

Tests
Cerebrospinal fluid (CSF) culture
A cerebrospinal fluid (CSF) culture is a laboratory test to look for bacteria, fungi, and viruses in the fluid that moves in the space around the spinal cord. CSF protects the brain and spinal cord from...

Diseases & Conditions
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth disease is a group of disorders passed down through families that affect the nerves outside the brain and spine. These are called the peripheral nerves.

Tests
Cholinesterase - blood
Serum cholinesterase is a blood test that looks at levels of 2 substances that help the nervous system work properly. They are called acetylcholinesterase and pseudocholinesterase. Your nerves need these...

Special Topics
Choroid
The choroid is the layer of blood vessels and connective tissue between the white of the eye and retina (at the back of the eye). It is part of the uvea and supplies nutrients to the inner parts of the...

Diseases & Conditions
Chronic inflammatory demyelinating polyneuropathy
Chronic inflammatory demyelinating polyneuropathy (CIDP) is a disorder that involves nerve swelling and irritation (inflammation) that leads to a loss of strength or sensation.

Diseases & Conditions
Chronic motor or vocal tic disorder
Chronic motor or vocal tic disorder is a condition that involves quick, uncontrollable movements or vocal outbursts (but not both).

Diseases & Conditions
Chronic subdural hematoma
A chronic subdural hematoma is an "old" collection of blood and blood breakdown products between the surface of the brain and its outermost covering (the dura). The chronic phase of a subdural hematoma...

Diseases & Conditions
Cluster headache
A cluster headache is an uncommon type of headache. It is one-sided head pain that may involve tearing of the eyes, a droopy eyelid, and a stuffy nose. Attacks last from 15 minutes to 3 hours, occur daily...

Diseases & Conditions
Common peroneal nerve dysfunction
Common peroneal nerve dysfunction is due to damage to the peroneal nerve leading to loss of movement or sensation in the foot and leg. This condition is also called common fibular nerve dysfunction.

Self-Care Instructions
Communicating with someone with aphasia
Stroke - aphasia; Speech and language disorder - aphasia

Self-Care Instructions
Communicating with someone with dysarthria
Speech and language disorder - dysarthria care; Slurred speech - dysarthria; Articulation disorder - dysarthria

Diseases & Conditions
Complex regional pain syndrome
Complex regional pain syndrome (CRPS) is a long-term (chronic) pain condition that can affect any area of the body, but often affects an arm or a leg.

Diseases & Conditions
Concussion
A concussion may occur when the head hits an object, or a moving object strikes the head. A concussion is a less severe type of brain injury. It may also be called a traumatic brain injury. A concussion...

Discharge Instructions
Concussion in adults - discharge
Brain injury - concussion - discharge; Traumatic brain injury - concussion - discharge; Closed head injury - concussion - discharge

Questions To Ask Your Doctor
Concussion in adults - what to ask your doctor
What to ask your doctor about concussion - adult; Adult brain injury - what to ask your doctor; Traumatic brain injury - what to ask the doctor

Discharge Instructions
Concussion in children - discharge
Mild brain injury in children - discharge; Brain injury in children - discharge; Mild traumatic brain injury in children - discharge; Closed head injury in children - discharge; TBI in children - discharge

Symptoms
Confusion
Confusion is the inability to think as clearly or quickly as you normally do. You may feel disoriented and have difficulty paying attention, remembering, and making decisions.

Symptoms
Contracture deformity
A contracture develops when the normally stretchy (elastic) tissues are replaced by nonstretchy (inelastic) fiber-like tissue. This tissue makes it hard to stretch the area and prevents normal movement...

Diseases & Conditions
Cranial mononeuropathy III
Cranial mononeuropathy III is a nerve disorder. It affects the function of the third cranial nerve. As a result, the person may have double vision and eyelid drooping.

Diseases & Conditions
Cranial mononeuropathy III - diabetic type
This diabetic type of cranial mononeuropathy III is a complication of diabetes. It causes double vision and eyelid drooping. diabetes eyelid drooping

Diseases & Conditions
Cranial mononeuropathy VI
Cranial mononeuropathy VI is a nerve disorder. It affects the function of the sixth cranial (skull) nerve. As a result, the person may have double vision.

Diseases & Conditions
Craniosynostosis
Craniosynostosis is a birth defect in which one or more sutures on a baby's head closes earlier than usual. The skull of an infant or young child is made up of bony plates that are still growing. The borders...

Diseases & Conditions
Creutzfeldt-Jakob disease
Creutzfeldt-Jakob disease (CJD) is a form of brain damage that leads to a rapid decrease in movement and loss of mental function.

Tests
D-dimer test
D-dimer tests are used to check for blood clotting problems. Blood clots can cause health problems, such as: Blood clots Deep vein thrombosis (DVT)Disseminated intravascular coagulation (DIC)Pulmonary embolism...

Self-Care Instructions
Daily bowel care program
Incontinence - care; Dysfunctional bowel - care; Neurogenic bowel - care

Symptoms
Decerebrate posture
Decerebrate posture is an abnormal body posture that involves the arms and legs being held straight out, the toes being pointed downward, and the head and neck being arched backward. The muscles are tightened...

Symptoms
Decorticate posture
Decorticate posture is an abnormal posturing in which a person is stiff with bent arms, clenched fists, and legs held out straight. The arms are bent in toward the body and the wrists and fingers are bent...

Symptoms
Decreased alertness
Decreased alertness is a state of reduced awareness and is often a serious condition. A coma is the most severe state of decreased alertness from which a person cannot be awakened. A long-term coma is called...

Surgery
Deep brain stimulation
Deep brain stimulation (DBS) uses a device called a neurostimulator to deliver electrical signals to the areas of the brain that control movement, pain, mood, weight, obsessive-compulsive thoughts, and...

Diseases & Conditions
Delirium
Delirium is sudden severe confusion due to rapid changes in brain function that occur with physical or mental illness. confusion

Diseases & Conditions
Dementia
Dementia is a loss of brain function that occurs with certain diseases. It affects one or more brain functions such as memory, thinking, language, judgment, or behavior. Dementia may also be referred to...

Self-Care Instructions
Dementia - behavior and sleep problems
Sundowning - care

Self-Care Instructions
Dementia - daily care

Special Topics
Dementia - home care
Dementia is a loss of cognitive function that occurs with certain diseases. It affects memory, thinking, and behavior.

Self-Care Instructions
Dementia - keeping safe in the home

Questions To Ask Your Doctor
Dementia - what to ask your doctor
What to ask your doctor about dementia; Alzheimer disease - what to ask your doctor; Cognitive impairment - what to ask your doctor

Self-Care Instructions
Dementia and driving

Diseases & Conditions
Dementia due to metabolic causes
Dementia is loss of brain function that occurs with certain diseases. Dementia may also be referred to as major neurocognitive disorder. Dementia neurocognitive disorder Dementia due to metabolic causes...

Diseases & Conditions
Developmental coordination disorder
Developmental coordination disorder is a childhood disorder. It leads to poor coordination and clumsiness.

Diseases & Conditions
Developmental expressive language disorder
Developmental expressive language disorder is a condition in which a child has lower than normal ability in vocabulary, saying complex sentences, and remembering words. However, a child with this disorder...

Special Topics
Developmental milestones record - 12 months
The typical 12-month-old child will demonstrate certain physical and mental skills. These skills are called developmental milestones.

Special Topics
Developmental milestones record - 18 months
The typical 18-month-old child will demonstrate certain physical and mental skills. These skills are called developmental milestones.

Special Topics
Developmental milestones record - 2 months
This article describes the skills and growth targets of 2-month-old infants.

Special Topics
Developmental milestones record - 2 years
Physical and motor skill markers: Able to turn a door knob.Can look through a book turning one page at a time.Can build a tower of 6 to 7 cubes.Can kick a ball without losing balance.Can pick up objects...

Special Topics
Developmental milestones record - 3 years
This article describes the skills and growth markers that are relevant to 3-year-olds.

Special Topics
Developmental milestones record - 4 months
Typical 4-month-old infants are expected to develop certain physical and mental skills. These skills are called milestones.

Special Topics
Developmental milestones record - 4 years
The typical 4-year-old child will demonstrate certain physical and mental skills. These skills are called developmental milestones.

Special Topics
Developmental milestones record - 5 years
This article describes the expected skills and growth markers of most 5-year-old children.

Special Topics
Developmental milestones record - 6 months
This article describes the skills and growth targets for 6-month-old infants.

Special Topics
Developmental milestones record - 9 months
At 9 months, a typical infant will have certain skills and reach growth markers called milestones.

Diseases & Conditions
Developmental reading disorder
Developmental reading disorder is a reading disability that occurs when the brain does not properly recognize and process certain symbols. It is also called dyslexia.

Nutrition
Diet - chronic kidney disease
You may need to make changes to your diet when you have chronic kidney disease (CKD). These changes may include limiting fluids, eating a low-protein diet, limiting salt, potassium, phosphorous, and other...

Diseases & Conditions
Dificultad con la deglución
Es la sensación de que el alimento sólido o líquido se atora en la garganta o en cualquier punto antes de que este ingrese al estómago. Este problema también se denomina disfagia.

Diseases & Conditions
Distal median nerve dysfunction
Distal median nerve dysfunction is a form of peripheral neuropathy that affects the movement of or sensation in the hands. peripheral neuropathy A common type of distal median nerve dysfunction is carpal...

Symptoms
Dizziness
Dizziness is a term that is often used to describe 2 different symptoms: lightheadedness and vertigo. Lightheadedness is a feeling that you might faint. Vertigo is a feeling that you are spinning or moving...

Self-Care Instructions
Dizziness and vertigo - aftercare
Meniere disease - aftercare; Benign positional vertigo - aftercare

Diseases & Conditions
Drug-induced tremor
Drug-induced tremor is involuntary shaking due to the use of medicines. Involuntary means you shake without trying to do so and can't stop when you try. The shaking occurs when you move or try to hold your...

Self-Care Instructions
Dry mouth during cancer treatment
Chemotherapy - dry mouth; Radiation therapy - dry mouth; Transplant - dry mouth; Transplantation - dry mouth

Diseases & Conditions
Duchenne muscular dystrophy
Duchenne muscular dystrophy is an inherited disorder. It involves muscle weakness, which quickly gets worse. muscle weakness

Diseases & Conditions
Dysarthria
Dysarthria is a condition in which you have difficulty saying words because of problems with the muscles that help you talk.

Tests
EEG
An electroencephalogram (EEG) is a test to measure the electrical activity of the brain.

Tests
Electromyography
Electromyography (EMG) is a test that checks the health of the muscles and the nerves that control the muscles.

Tests
Electronystagmography
Electronystagmography is a test that looks at eye movements to see how well nerves in the brain are working. These nerves are: Vestibular nerve (eighth cranial nerve), which runs from the brain to the earsOculomotor...

Diseases & Conditions
Empty sella syndrome
Empty sella syndrome is a condition in which the pituitary gland shrinks or becomes flattened.

Diseases & Conditions
Encephalitis
Encephalitis is irritation and swelling (inflammation) of the brain, most often due to infections.

Surgery
Endovascular embolization
Endovascular embolization is a procedure to treat abnormal blood vessels in the brain and other parts of the body. It is an alternative to open surgery. This procedure cuts off the blood supply to a certain...

Diseases & Conditions
Epidural abscess
An epidural abscess is a collection of pus (infected material) and germs between the outer covering of the brain and spinal cord and the bones of the skull or spine. The abscess causes swelling in the area...

Diseases & Conditions
Epidural hematoma
An epidural hematoma (EDH) is bleeding between the inside of the skull and the outer covering of the brain (called the dura mater).

Diseases & Conditions
Epilepsy
Epilepsy is a brain disorder in which a person has repeated seizures over time. Seizures are episodes of uncontrolled and abnormal electrical activity of brain cells that may cause changes in attention...

In-depth Report
Epilepsy - InDepth
An in-depth report on the types, causes, diagnosis, and treatment of epilepsy.

Special Topics
Epilepsy - resources

Questions To Ask Your Doctor
Epilepsy in adults - what to ask your doctor
What to ask your doctor about epilepsy - adult; Seizures - what to ask your doctor - adult; Seizure - what to ask your doctor

Diseases & Conditions
Epilepsy in children
Epilepsy is a brain disorder in which a person has repeated seizures over time. seizures A seizure is a sudden change in the electrical and chemical activity in the brain. A single seizure that does not...

Discharge Instructions
Epilepsy in children - discharge
Seizure disorder in children - discharge

Questions To Ask Your Doctor
Epilepsy in children - what to ask your doctor
What to ask your doctor about epilepsy - child; Seizures - what to ask your doctor - child

Discharge Instructions
Epilepsy or seizures - discharge
Focal seizure - discharge; Jacksonian seizure - discharge; Seizure - partial (focal) - discharge; TLE - discharge; Seizure - temporal lobe - discharge; Seizure - tonic-clonic - discharge; Seizure - grand...

Diseases & Conditions
Essential tremor
Essential tremor (ET) is a type of involuntary shaking movement. It has no identified cause. Involuntary means you shake without trying to do so and are not able to stop the shaking at will.

Tests
Eye and orbit ultrasound
An eye and orbit ultrasound is a test to look at the eye area. It also measures the size and structures of the eye. ultrasound

Diseases & Conditions
Eyelid twitch
An eyelid twitch is a general term for spasms of the eyelid muscles. These spasms happen without your control. The eyelid may repeatedly close (or nearly close) and reopen. This article discusses eyelid...

Diseases & Conditions
Facial nerve palsy due to birth trauma
Facial nerve palsy due to birth trauma is the loss of controllable (voluntary) muscle movement in an infant's face due to pressure on the facial nerve just before or at the time of birth.

Symptoms
Facial paralysis
Facial paralysis means that a person is no longer able to move some or all of the muscles on one or both sides of the face.

Diseases & Conditions
Facial tics
A facial tic is a repeated spasm, often involving the eyes and muscles of the face.

Diseases & Conditions
Facioscapulohumeral muscular dystrophy
Facioscapulohumeral muscular dystrophy is a condition that causes muscle weakness and loss of muscle tissue that gets worse over time. muscle weakness

Symptoms
Fainting
Fainting is a brief loss of consciousness due to a drop in blood flow to the brain. The episode most often lasts less than a couple of minutes and you usually recover from it quickly. The medical name for...

Diseases & Conditions
Femoral nerve dysfunction
Femoral nerve dysfunction is a loss of movement or sensation in parts of the legs due to damage to the femoral nerve.

Special Topics
Fine motor control

Symptoms
Focal neurologic deficits
A focal neurologic deficit is a problem with nerve, spinal cord, or brain function. It affects a specific location, such as the left side of the face, right arm, or even a small area such as the tongue...

Diseases & Conditions
Focal seizure
All seizures are caused by abnormal electrical disturbances in the brain. Focal seizures occur when this electrical activity is in a limited area of the brain. Sometimes the seizures stay only in one part...

Diseases & Conditions
Foot drop
Foot drop is when you have difficulty lifting the front part of your foot. This may cause you to drag your foot when you walk. Foot drop, also called drop foot, can be caused by a problem with the muscles...

Diseases & Conditions
Friedreich ataxia
Friedreich ataxia is a rare disease passed down through families (inherited). It affects the muscles and heart.

Diseases & Conditions
Frontotemporal dementia
Frontotemporal dementia (FTD) is a rare form of dementia that is similar to Alzheimer disease, except that it tends to affect only certain areas of the brain. dementia Alzheimer disease Dementia may also...

Diseases & Conditions
Ganglioneuroma
Ganglioneuroma is a tumor of the autonomic nervous system.

Diseases & Conditions
General paresis
General paresis is a problem with mental function due to damage to the brain from untreated syphilis.

Diseases & Conditions
Giant cell arteritis
Giant cell arteritis (GCA) is inflammation and damage to the blood vessels that supply blood to the head, neck, upper body and arms. It is also called temporal arteritis.

Diseases & Conditions
Gigantism
Gigantism is abnormal growth due to an excess of growth hormone (GH) during childhood. growth hormone

Diseases & Conditions
Glossopharyngeal neuralgia
Glossopharyngeal neuralgia is a rare condition in which there are repeated episodes of severe pain in the tongue, throat, ear, and tonsils. This can last from a few seconds to a few minutes.

Special Topics
Gross motor control
Gross motor control is the ability to make large, general movements (such as waving an arm or lifting a leg). It requires proper coordination and function of muscle, bones, and nerves.

Diseases & Conditions
Guillain-Barre syndrome
Guillain-Barré syndrome (GBS) is a serious health problem that occurs when the body's defense (immune) system mistakenly attacks part of the peripheral nervous system. This leads to nerve inflammation that...

Symptoms
Hand or foot spasms
Spasms are contractions of the muscles of the hands, thumbs, feet, or toes. Spasms are usually brief, but they can be severe and painful.

Tests
Head CT scan
A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses. computed tomography

Tests
Head MRI
A head MRI (magnetic resonance imaging) is an imaging test that uses powerful magnets and radio waves to create pictures of the brain and surrounding tissues. It does not use radiation.

Special Topics
Head circumference
Head circumference is a measurement of a child's head around its largest area. It measures the distance from above the eyebrows and ears and around the back of the head.

Symptoms
Headache
A headache is pain or discomfort in the head, scalp, or neck. Serious causes of headaches are rare. Most people with headaches can feel much better by making lifestyle changes, learning ways to relax, and...

Questions To Ask Your Doctor
Headache - what to ask your doctor
What to ask your doctor about headaches; Migraine - what to ask your doctor; Tension-type headache - what to ask your doctor; Cluster headache - what to ask your doctor

In-depth Report
Headaches - cluster - InDepth
An in-depth report on the causes, diagnosis, treatment, and prevention of cluster headaches.

Self-Care Instructions
Headaches - danger signs
Migraine headache - danger signs; Tension headache - danger signs; Cluster headache - danger signs; Vascular headache - danger signs

In-depth Report
Headaches - tension - InDepth
An in-depth report on the causes, diagnosis, treatment, and prevention of common headaches.

Diseases & Conditions
Hepatocerebral degeneration
Hepatocerebral degeneration is a brain disorder that occurs in people with liver damage.

Diseases & Conditions
Horner syndrome
Horner syndrome is a rare condition that affects the nerves to the eye and face.

Diseases & Conditions
Huntington disease
Huntington disease (HD) is a genetic disorder in which nerve cells in certain parts of the brain waste away, or degenerate. The disease is passed down through families.

Diseases & Conditions
Hydrocephalus
Hydrocephalus is a buildup of fluid inside the skull that leads to the brain pushing against the skull. Hydrocephalus means "water on the brain."

Diseases & Conditions
Hypopituitarism
Hypopituitarism is a condition in which the pituitary gland does not produce normal amounts of some or all of its hormones.

Diseases & Conditions
Idiopathic intracranial hypertension
Idiopathic intracranial hypertension (IIH) is a condition in which the pressure inside the skull is increased. The brain is affected in a way that the condition appears to be, but is not, a tumor.

Diseases & Conditions
Increased intracranial pressure
Increased intracranial pressure is a rise in the pressure inside the skull that can result from or cause brain injury.

Special Topics
Infant - newborn development

Symptoms
Infant reflexes
A reflex is a muscle reaction that happens automatically in response to stimulation. Certain sensations or movements produce specific muscle responses.

Diseases & Conditions
Intellectual disability
Intellectual disability is a condition diagnosed before age 18 that includes below-average intellectual function and a lack of skills necessary for daily living. In the past, the term mental retardation...

Tests
Intracranial pressure monitoring
Intracranial pressure (ICP) monitoring uses a device placed inside the head. The monitor senses the pressure inside the skull and sends measurements to a recording device.

Diseases & Conditions
Kuru
Kuru is a disease of the nervous system.

Diseases & Conditions
Labyrinthitis
Labyrinthitis is irritation and swelling of the inner ear. It can cause vertigo and hearing loss.

Diseases & Conditions
Lambert-Eaton myasthenic syndrome
Lambert-Eaton myasthenic syndrome (LEMS) is a rare disorder in which faulty communication between nerves and muscles leads to muscle weakness. muscle weakness

Diseases & Conditions
Language disorders in children
Language disorders in children are problems with the development of language skills. Children may have problems with one or both of the following: Getting their meaning or message across to others (expressive...

Diseases & Conditions
Lesch-Nyhan syndrome
Lesch-Nyhan syndrome is a disorder that is passed down through families (inherited). It affects how the body builds and breaks down purines. Purines are a normal part of human tissue that help make up the...

Diseases & Conditions
Limb-girdle muscular dystrophies
Limb-girdle muscular dystrophies include at least 33 different inherited diseases. (There are 16 known genetic forms. ) These disorders first affect the muscles around the shoulder girdle and hips. These...

Self-Care Instructions
Managing migraines at home
Headache - migraine - self-care; Vascular headache - self-care

Self-Care Instructions
Managing tension headaches at home
Tension-type headache - self-care; Muscle contraction headache - self-care; Headache - benign - self-care; Headache - tension- self-care; Chronic headaches - tension - self-care; Rebound headaches - tension...

Self-Care Instructions
Managing your chronic back pain
Chronic back pain - managing; Chronic back pain - self-care; Failed back syndrome - managing; Lumbar stenosis -managing; Spinal stenosis - managing; Sciatica - managing; Chronic lumbar pain - managing

Symptoms
Memory loss
Memory loss is unusual forgetfulness. You may not be able to remember new events, recall one or more memories of the past, or both. The memory loss may be for a short time and then resolve (transient)....

Diseases & Conditions
Meniere disease
Ménière disease is an inner ear disorder that affects balance and hearing.

Special Topics
Meniere disease - self-care
Hydrops - self-care; Endolymphatic hydrops - self-care; Dizziness - Ménière self-care; Vertigo - Ménière self-care; Loss of balance - Ménière self-care; Primary endolymphatic hydrops - self-care; Auditory...

Surgery
Meningocele repair
Meningocele repair (also known as myelomeningocele repair) is surgery to repair birth defects of the spine and spinal membranes. Meningocele and myelomeningocele are types of spina bifida. spina bifida

Tests
Mental status testing
Mental status testing is done to check a person's thinking ability and to determine if any problems are getting better or worse. It is also called neurocognitive testing.

Diseases & Conditions
Metabolic neuropathies
Metabolic neuropathies are nerve disorders that occur with diseases that disrupt the chemical processes in the body

Diseases & Conditions
Migraine
A migraine is a type of headache. It may occur with symptoms such as nausea, vomiting, or sensitivity to light and sound. In most people, a throbbing pain is felt only on one side of the head.

Special Topics
Migraine - resources

In-depth Report
Migraine headaches - InDepth
An in-depth report on the causes, diagnosis, treatment, and prevention of migraine.

Diseases & Conditions
Mononeuropathy
Mononeuropathy is damage to a single nerve, which results in loss of movement, sensation, or other function of that nerve. loss of movement

Symptoms
Moro reflex
A reflex is a type of involuntary (without trying) response to stimulation. The Moro reflex is one of many reflexes that are seen at birth. It normally goes away after 3 or 4 months. reflexes

Symptoms
Movement - uncontrollable
Uncontrollable movements include many types of movements that you cannot control. They can affect the arms, legs, face, neck, or other parts of the body. Examples of uncontrollable movements are: Loss of...

Symptoms
Movement - uncontrolled or slow
Uncontrolled or slow movement is a problem with muscle tone, usually in the large muscle groups. The problem leads to slow, uncontrollable jerky movements of the head, limbs, trunk, or neck.

Symptoms
Movement - uncoordinated
Uncoordinated movement is due to a muscle control problem that causes an inability to coordinate movements. It leads to a jerky, unsteady, to-and-fro motion of the middle of the body (trunk) and an unsteady...

Symptoms
Movement - unpredictable or jerky
Jerky body movement is a condition in which a person makes fast movements that they cannot control and that have no purpose. These movements interrupt the person's normal movement or posture. When abnormal...

Diseases & Conditions
Mucormycosis
Mucormycosis is a fungal infection of the sinuses, brain, or lungs. It occurs in some people with a weakened immune system.

Diseases & Conditions
Multiple mononeuropathy
Multiple mononeuropathy is a nervous system disorder that involves damage to at least two separate nerve areas. Neuropathy means damage to a peripheral nerve.

Diseases & Conditions
Multiple sclerosis
Multiple sclerosis (MS) is an autoimmune disease that affects the brain and spinal cord (central nervous system). autoimmune disease brain and spinal cord

In-depth Report
Multiple sclerosis - InDepth
An in-depth report on the causes, diagnosis, and treatment of MS.

Discharge Instructions
Multiple sclerosis - discharge
MS - discharge

Special Topics
Multiple sclerosis - resources

Diseases & Conditions
Multiple system atrophy - cerebellar subtype
Multiple system atrophy - cerebellar subtype (MSA-C) is a rare disease that causes areas deep in the brain, just above the spinal cord, to shrink (atrophy). MSA-C used to be known as olivopontocerebellar...

Diseases & Conditions
Multiple system atrophy - parkinsonian type
Multiple system atrophy- parkinsonian type (MSA-P) is a rare condition that causes symptoms similar to Parkinson disease. However, people with MSA-P have more widespread damage to the part of the nervous...

Symptoms
Muscle atrophy
Muscle atrophy is the wasting (thinning) or loss of muscle tissue.

Diseases & Conditions
Muscle disorder
A muscle disorder includes patterns of weakness, loss of muscle tissue, electromyogram (EMG) findings, or biopsy results that suggest a muscle problem. The muscle disorder can be inherited, such as muscular...

Symptoms
Muscle function loss
Muscle function loss is when a muscle does not work or move normally. The medical term for complete loss of muscle function is paralysis.

Symptoms
Muscle twitching
Muscle twitches are fine movements of a small area of muscle.

Diseases & Conditions
Muscular dystrophy
Muscular dystrophy is a group of inherited disorders that cause muscle weakness and loss of muscle tissue, which get worse over time. muscle weakness

Special Topics
Muscular dystrophy - resources

Diseases & Conditions
Myasthenia gravis
Myasthenia gravis is a neuromuscular disorder. Neuromuscular disorders involve the muscles and the nerves that control them.

Special Topics
Myasthenia gravis - resources

Special Topics
Myelin
Myelin is an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord. It is made up of protein and fatty substances. This myelin sheath allows electrical impulses...

Diseases & Conditions
Myelomeningocele
Myelomeningocele is a birth defect in which the backbone and spinal canal do not close fully before birth. The condition is a type of neural tube defect (NTD).

Diseases & Conditions
Myotonia congenita
Myotonia congenita is an inherited condition that affects muscle relaxation. It is congenital, meaning that it is present from birth. It occurs more frequently in northern Scandinavia.

Diseases & Conditions
Narcolepsy
Narcolepsy is a nervous system problem that causes extreme sleepiness and attacks of daytime sleep.

In-depth Report
Narcolepsy - InDepth
An in-depth report on the causes, diagnosis, and treatment of narcolepsy.

Tests
Nerve biopsy
A nerve biopsy is the removal of a small piece of a nerve for examination.

Tests
Nerve conduction velocity
Nerve conduction velocity (NCV) is a test to see how fast electrical signals move through a nerve. This test is done along with electromyography (EMG) to assess the muscles for abnormalities. electromyography...

Self-Care Instructions
Nerve damage from diabetes - self-care
Diabetic neuropathy - self-care

Diseases & Conditions
Neuralgia
Neuralgia is a sharp, shocking pain that follows the path of a nerve and is due to irritation or damage to the nerve. Common neuralgias include: Postherpetic neuralgia (pain that continues after a bout...

Diseases & Conditions
Neurocognitive disorder
Neurocognitive disorder is a general term that describes decreased mental function due to a medical disease other than a psychiatric illness. Neurocognitive disorders are grouped into three subcategories...

Diseases & Conditions
Neurodegeneration with brain iron accumulation (NBIA)
Neurodegeneration with brain iron accumulation (NBIA) are a group of very rare nervous system disorders. They are passed down through families (inherited). NBIA involves movement problems, dementia, and...

Diseases & Conditions
Neurogenic bladder
Neurogenic bladder is a problem in which a person lacks bladder control due to a brain, spinal cord, or nerve condition.

Special Topics
Neurologic deficit

Diseases & Conditions
Neuropathy secondary to drugs
Neuropathy is injury to one or more peripheral nerves. These are nerves that are not in the brain or spinal cord. Neuropathy secondary to drugs causes a loss of sensation or movement in a part of the body...

Diseases & Conditions
Neurosarcoidosis
Neurosarcoidosis is a form of sarcoidosis, in which inflammation occurs in the brain, spinal cord, and other areas of the nervous system. sarcoidosis

Special Topics
Neurosciences
Neurosciences refers to the branch of medicine that focuses on the nervous system. The nervous system is made of two parts: The central nervous system (CNS) consists of your brain and spinal cord. The peripheral...

Diseases & Conditions
Neurosyphilis
Neurosyphilis is a bacterial infection of the brain or spinal cord. It usually occurs in people who have had untreated syphilis for many years. syphilis

Diseases & Conditions
Night terrors in children
Night terrors (sleep terrors) are a sleep disorder in which a person quickly wakes from sleep in a terrified state.

Nutrition
Normal growth and development
A child's growth and development can be divided into four periods: InfancyPreschool yearsMiddle childhood yearsAdolescence Infancy Preschool years Middle childhood years Adolescence Soon after birth, an...

Diseases & Conditions
Normal pressure hydrocephalus
Hydrocephalus is a buildup of spinal fluid inside the fluid chambers of the brain. Hydrocephalus means "water on the brain." Normal pressure hydrocephalus (NPH) is a rise in the amount of cerebrospinal...

Symptoms
Numbness and tingling
Numbness and tingling are abnormal sensations that can occur anywhere in your body, but they are often felt in your fingers, hands, feet, arms, or legs.

Symptoms
Nystagmus
Nystagmus is a term to describe uncontrollable movements of the eyes that may be: Side to side (horizontal nystagmus)Up and down (vertical nystagmus)Rotary (rotary or torsional nystagmus) Side to side ...

Symptoms
Opisthotonos
Opisthotonos is a condition in which a person holds their body in an abnormal position. The person is usually rigid and arches their back, with their head thrown backward. If a person with opisthotonos...

Diseases & Conditions
Optic glioma
Gliomas are tumors that grow in various parts of the brain. Optic gliomas can affect: One or both of the optic nerves that carry visual information to the brain from each eyeThe optic chiasm, the area where...

Diseases & Conditions
Osmotic demyelination syndrome
Osmotic demyelination syndrome (ODS) leads to brain cell dysfunction. It is caused by the destruction of the layer (myelin sheath) covering nerve cells in the middle of the brainstem (pons). myelin sheath

Special Topics
Pain medications - narcotics
Narcotics are also called opioid pain relievers. They are only used for pain that is severe and is not helped by other types of painkillers. When used carefully and under a health care provider's direct...

Diseases & Conditions
Parkinson disease
Parkinson disease results from certain brain cells dying. These cells help control movement and coordination. The disease leads to shaking (tremors) and trouble walking and moving. tremors trouble walking...

In-depth Report
Parkinson disease - InDepth
An in-depth report on the causes, diagnosis, and treatment of Parkinson disease.

Discharge Instructions
Parkinson disease - discharge
Paralysis agitans - discharge; Shaking palsy - discharge; PD - discharge

Special Topics
Parkinson disease - resources

Diseases & Conditions
Peripheral neuropathy
Peripheral nerves carry information to and from the brain. They also carry signals to and from the spinal cord to the rest of the body. Peripheral neuropathy means these nerves don't work properly. Peripheral...

Self-Care Instructions
Phantom limb pain
Amputation - phantom limb

Diseases & Conditions
Phonological disorder
Phonological disorder is a type of speech sound disorder. Speech sound disorders are the inability to correctly form the sounds of words. Speech sound disorders also include articulation disorder, disfluency...

Special Topics
Physical medicine and rehabilitation
Physical medicine and rehabilitation is a medical specialty that helps people regain body functions they lost due to medical conditions or injury. This term is often used to describe the whole medical team...

Diseases & Conditions
Polio
Polio is a viral disease that can affect nerves and can lead to partial or full paralysis. The medical name for polio is poliomyelitis. paralysis

Self-Care Instructions
Postherpetic neuralgia - aftercare
Herpes zoster - postherpetic neuralgia; Varicella-zoster - postherpetic neuralgia; Shingles - pain; PHN

Diseases & Conditions
Prader-Willi syndrome
Prader-Willi syndrome is a disease that is present from birth (congenital). It affects many parts of the body. People with this condition feel hungry all the time and become obese. They also have poor muscle...

Special Topics
Preschooler development
The normal social and physical development of children ages 3 to 6 years old includes many milestones.

Self-Care Instructions
Preventing falls
Home safety; Safety in the home; Fall prevention

Questions To Ask Your Doctor
Preventing falls - what to ask your doctor
Fall prevention - what to ask your doctor

Self-Care Instructions
Preventing head injuries in children
Concussion - preventing in children; Traumatic brain injury - preventing in children; TBI - children; Safety - preventing head injury

Special Topics
Preventing stroke
Stroke - prevention; CVA - prevention; Cerebral vascular accident - prevention; TIA - prevention, Transient ischemic attack - prevention

Diseases & Conditions
Progressive multifocal leukoencephalopathy
Progressive multifocal leukoencephalopathy (PML) is a rare infection that damages the material (myelin) that covers and protects nerves in the white matter of the brain. myelin white matter of the brain

Diseases & Conditions
Progressive supranuclear palsy
Progressive supranuclear palsy (PSP) is a movement disorder that occurs from damage to certain nerve cells in the brain.

Tests
Prolactin blood test
Prolactin is a hormone released by the pituitary gland. The prolactin test measures the amount of prolactin in the blood.

Diseases & Conditions
Prolactinoma
A prolactinoma is a noncancerous (benign) pituitary tumor that produces a hormone called prolactin. This results in too much prolactin in the blood.

Diseases & Conditions
Provisional tic disorder
Provisional (transient) tic disorder is a condition in which a person makes one or many brief, repeated, movements or noises (tics). These movements or noises are involuntary (not on purpose).

Diseases & Conditions
Rabies
Rabies is a deadly viral infection that is mainly spread by infected animals.

Diseases & Conditions
Radial nerve dysfunction
Radial nerve dysfunction is a problem with the radial nerve. This is the nerve that travels from the armpit down the back of the arm to the hand. It helps you move your arm, wrist, and hand.

Tests
Radionuclide cisternogram
A radionuclide cisternogram is a nuclear scan test. It is used to diagnose problems with the flow of spinal fluid.

Diseases & Conditions
Ramsay Hunt syndrome
Ramsay Hunt syndrome is a painful rash around the ear, on the face, or on the mouth. It occurs when the varicella-zoster virus infects a nerve in the head. varicella-zoster

Special Topics
Recovering after stroke
A stroke happens when blood flow to any part of the brain stops. stroke Each person has a different recovery time and need for long-term care. Problems with moving, thinking, and talking often improve in...

Special Topics
Remembering tips
People who have early memory loss can use a number of techniques to help with remembering things. Below are some tips.

Diseases & Conditions
Restless legs syndrome
Restless legs syndrome (RLS) is a nervous system problem that causes you to feel an unstoppable urge to get up and pace or walk. You feel uncomfortable unless you move your legs. Moving stops the unpleasant...

In-depth Report
Restless legs syndrome and related disorders - InDepth
An in-depth report on the causes, diagnosis, treatment, and prevention of RLS.

Diseases & Conditions
Rett syndrome
Rett syndrome (RTT) is a disorder of the nervous system. This condition leads to developmental problems in children. It mostly affects language skills and hand use.

Special Topics
School-age children development
School-age child development describes the expected physical, emotional, and mental abilities of children ages 6 to 12 years.

Diseases & Conditions
Secondary parkinsonism
Secondary parkinsonism is when symptoms similar to Parkinson disease are caused by certain medicines, a different nervous system disorder, or another illness. Parkinsonism refers to any condition that involves...

Symptoms
Seizures
A seizure is the physical changes in behavior that occurs during an episode of specific types of abnormal electrical activity in the brain. The term "seizure" is often used interchangeably with "convulsion...

Diseases & Conditions
Sensorimotor polyneuropathy
Sensorimotor polyneuropathy is a condition that causes a decreased ability to move and feel (sensation) because of nerve damage.

Symptoms
Sensorineural deafness
Sensorineural deafness is a type of hearing loss. It occurs from damage to the inner ear, the place of origin of the nerve that runs from the ear to the brain (auditory nerve), or the brain.

Self-Care Instructions
Shingles - aftercare
Herpes zoster - treatment

In-depth Report
Shingles and chickenpox (Varicella-zoster virus) - InDepth
An in-depth report on the causes, diagnosis, treatment, and prevention of shingles and chickenpox.

Surgery
Simple prostatectomy
Simple prostate removal is a procedure to remove the inside part of the prostate gland to treat an enlarged prostate. It is done through a surgical cut in your lower belly. enlarged prostate

Diseases & Conditions
Sleepwalking
Sleepwalking is a disorder that occurs when people walk or do other activity while they are still asleep.

Diseases & Conditions
Spasmodic dysphonia
Spasmodic dysphonia is difficulty speaking due to spasms (dystonia) of the muscles that control the vocal cords.

Diseases & Conditions
Spasmus nutans
Spasmus nutans is a disorder affecting infants and young children. It involves rapid, uncontrolled eye movements, head bobbing, and sometimes, holding the neck in an abnormal position.

Symptoms
Spasticity
Spasticity is stiff or rigid muscles. It may also be called unusual tightness or increased muscle tone. Reflexes (for example, a knee-jerk reflex) are stronger or exaggerated. The condition can interfere...

Diseases & Conditions
Speech disorders - children
A speech disorder is a condition in which a person has problems creating or forming the speech sounds needed to communicate with others. This can make the child's speech difficult to understand. Common...

Symptoms
Speech impairment in adults
Speech and language impairment may be any of several problems that make it difficult to communicate.

Diseases & Conditions
Spinal cord abscess
Spinal cord abscess is the swelling and irritation (inflammation) and the collection of infected material (pus) and germs in or around the spinal cord.

Diseases & Conditions
Spinal cord trauma
Spinal cord trauma is damage to the spinal cord. It may result from direct injury to the cord itself or indirectly from disease of the nearby bones, tissues, or blood vessels.

Diseases & Conditions
Spinal muscular atrophy
Spinal muscular atrophy (SMA) is a group of disorders of the motor neurons (motor cells). These disorders are passed down through families (inherited) and can appear at any stage of life. The disorder leads...

Self-Care Instructions
Staying safe at home
Carbon monoxide safety; Electrical safety; Furnace safety; Gas appliance safety; Water heater safety

Discharge Instructions
Stereotactic radiosurgery - discharge
Gamma Knife - discharge; CyberKnife - discharge; Stereotactic radiotherapy - discharge; Fractionated stereotactic radiotherapy - discharge; Cyclotrons - discharge; Linear accelerator - discharge; LINAC...

Diseases & Conditions
Stereotypic movement disorder
Stereotypic movement disorder is a condition in which a person makes repetitive, purposeless movements. These can be hand waving, body rocking, or head banging. The movements interfere with normal activity...

Diseases & Conditions
Stroke
A stroke occurs when blood flow to a part of the brain stops. A stroke is sometimes called a "brain attack." If blood flow is cut off for longer than a few seconds, the brain cannot get nutrients and oxygen...

In-depth Report
Stroke - InDepth
An in-depth report on the causes, diagnosis, treatment, and prevention of stroke.

Discharge Instructions
Stroke - discharge
Cerebrovascular disease - discharge; CVA - discharge; Cerebral infarction - discharge; Cerebral hemorrhage - discharge; Ischemic stroke - discharge; Stroke - ischemic - discharge; Stroke secondary to atrial...

Self-Care Instructions
Stroke risk factors
Preventing stroke; Stroke - prevention; CVA - prevention; TIA - prevention

Diseases & Conditions
Subacute combined degeneration
Subacute combined degeneration (SCD) is a disorder of the spine, brain, and nerves. It causes weakness, abnormal sensations, mental problems, and vision difficulties. weakness abnormal sensations vision...

Diseases & Conditions
Subacute sclerosing panencephalitis
Subacute sclerosing panencephalitis (SSPE) is a progressive, disabling, and deadly brain disorder related to measles (rubeola) infection. measles The disease develops many years after the measles infection...

Diseases & Conditions
Subarachnoid hemorrhage
Subarachnoid hemorrhage is bleeding in the area between the brain and the thin tissues that cover the brain. This area is called the subarachnoid space. Subarachnoid bleeding is an emergency and prompt...

Diseases & Conditions
Subdural effusion
A subdural effusion is a collection of cerebrospinal fluid (CSF) trapped between the surface of the brain and the outer lining of the brain (the dura matter). If this fluid becomes infected, the condition...

Diseases & Conditions
Subdural hematoma
A subdural hematoma is a collection of blood between the covering of the brain (dura) and the surface of the brain.

Diseases & Conditions
Supranuclear ophthalmoplegia
Supranuclear ophthalmoplegia is a condition that affects the movement of the eyes.

Diseases & Conditions
Swallowing difficulty
Difficulty with swallowing is the feeling that food or liquid is stuck in the throat or at any point before the food enters the stomach. This problem is also called dysphagia.

Diseases & Conditions
Swimming pool granuloma
A swimming pool granuloma is a long-term (chronic) skin infection. It is caused by the bacteria Mycobacterium marinum (M marinum). Mycobacterium marinum (M marinum)

Diseases & Conditions
Sydenham chorea
Sydenham chorea is a movement disorder that occurs after infection with specific bacteria called group A streptococcus.

Diseases & Conditions
Syphilitic aseptic meningitis
Syphilitic aseptic meningitis, or syphilitic meningitis, is a complication of untreated syphilis. It involves inflammation of the tissues covering the brain and spinal cord caused by this bacterial infection...

Diseases & Conditions
Syringomyelia
Syringomyelia is a cyst-like collection of cerebrospinal fluid (CSF) that forms in the spinal cord. Over time, it may damage the spinal cord.

Diseases & Conditions
Tabes dorsalis
Tabes dorsalis is a complication of untreated syphilis that involves muscle weakness and abnormal sensations. syphilis

Diseases & Conditions
Tardive dyskinesia
Tardive dyskinesia (TD) is a disorder that involves involuntary movements. Tardive means delayed and dyskinesia means abnormal movement.

Diseases & Conditions
Tarsal tunnel syndrome
Tarsal tunnel syndrome is a condition in which the tibial nerve is being compressed. This is the nerve in the ankle that allows feeling and movement to parts of the foot. Tarsal tunnel syndrome can lead...

Diseases & Conditions
Tay-Sachs disease
Tay-Sachs disease is a life-threatening disease of the nervous system passed down through families.

Tests
Tensilon test
The Tensilon test is a method to help diagnose myasthenia gravis. myasthenia gravis

Diseases & Conditions
Tension headache
A tension headache is the most common type of headache. It is pain or discomfort in the head, scalp, or neck, and is often associated with muscle tightness in these areas.

Special Topics
Thrombolytic therapy
Thrombolytic therapy is the use of drugs to break up or dissolve blood clots, which are the main cause of both heart attacks and stroke.

Diseases & Conditions
Tick paralysis
Tick paralysis is a loss of muscle function that results from a tick bite. tick bite

Special Topics
Toddler development
Toddlers are children ages 1 to 3. CHILD DEVELOPMENT THEORIES Cognitive (thought) development skills typical for toddlers include: Early use of instruments or toolsFollowing visual (then later, invisible...

Diseases & Conditions
Torticollis
Torticollis is a condition in which the neck muscles cause the head to tilt, turn or rotate to the side.

Diseases & Conditions
Tourette syndrome
Tourette syndrome is a condition that causes a person to make repeated, quick movements or sounds that they cannot control.

Tests
Transcranial Doppler ultrasound
Transcranial doppler ultrasound (TCD) is a diagnostic test. It measures blood flow to and within the brain.

Diseases & Conditions
Transient ischemic attack
A transient ischemic attack (TIA) occurs when blood flow to a part of the brain stops for a brief time. A person will have stroke-like symptoms for up to 24 hours. In most cases, the symptoms last for 1...

Diseases & Conditions
Transverse myelitis
Transverse myelitis is a condition caused by inflammation of the spinal cord. As a result, the covering (myelin sheath) around the nerve cells is damaged. This disturbs the signals between spinal nerves...

Symptoms
Tremor
A tremor is a type of shaking movement. A tremor is most often noticed in the hands and arms. It may affect any body part, including the head, tongue, or vocal cords.

Self-Care Instructions
Tremor - self-care
Shaking - self-care; Essential tremor - self-care; Familial tremor - self-care

Diseases & Conditions
Trigeminal neuralgia
Trigeminal neuralgia (TN) is a nerve disorder. It causes a stabbing or electric shock-like pain in parts of the face.

Diseases & Conditions
Ulnar nerve dysfunction
Ulnar nerve dysfunction is a problem with one of the nerves that travel from the shoulder to the hand, called the ulnar nerve. It helps you move your arm, wrist, and hand.

Diseases & Conditions
Vascular dementia
Dementia is a loss of brain function that occurs with certain diseases. It affects one or more brain functions such as memory, thinking, language, judgment, or behavior. Vascular dementia is caused by a...

Discharge Instructions
Ventriculoperitoneal shunt - discharge
Shunt - ventriculoperitoneal - discharge; VP shunt - discharge; Shunt revision - discharge; Hydrocephalus shunt placement - discharge

Diseases & Conditions
Vertebrobasilar circulatory disorders
Vertebrobasilar circulatory disorders are conditions in which the blood supply to the back of the brain is disrupted.

Diseases & Conditions
Vertigo-associated disorders
Vertigo is a sensation of motion or spinning that is often described as dizziness. Vertigo Vertigo is not the same as being lightheaded. People with vertigo feel as though they are actually spinning or...

In-depth Report
Viral encephalitis - InDepth
An in-depth report on the causes, diagnosis, treatment, and prevention of viral encephalitis.

Symptoms
Walking abnormalities
Walking abnormalities can be caused by many different types of problems. Problems with the joints, (such as arthritis), bones (such as deformities), circulation (such as peripheral vascular disease), or...

Diseases & Conditions
Wernicke-Korsakoff syndrome
Wernicke-Korsakoff syndrome is a brain disorder due to vitamin B1 (thiamine) deficiency. vitamin B1 (thiamine) deficiency

Special Topics
White matter of the brain