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Brain, Spinal Cord, and Nerve Disorders
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Biology of the Nervous System
Overview of the Nervous System
Brain
Cerebrum
Brain stem
Cerebellum
Meninges
Spinal Cord
Nerves
Somatic nervous system
Autonomic nervous system
Cranial nerves and spinal nerves
Effects of Aging on the Nervous System
Brain
Spinal cord
Peripheral nerves
Symptoms of Brain, Spinal Cord, and Nerve Disorders
Weakness
Causes
Common causes
Less common causes
Fatigue
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Essentials for Older Adults
Key Points
Numbness
Pathway for sensation
Causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Key Points
Memory Loss
Causes
Common causes
Less common causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
General measures
Medications
Safety and supportive measures
Key Points
More Information
Introduction to Symptoms of Brain, Spinal Cord, and Nerve Disorders
Muscle Cramps
Causes
Disorders that cause similar symptoms
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Prevention
Key Points
Diagnosis of Brain, Spinal Cord, and Nerve Disorders
Introduction to the Diagnosis of Brain, Spinal Cord, and Nerve Disorders
Medical History in Neurologic Disorders
Tests for Brain, Spinal Cord, and Nerve Disorders
Imaging Tests
Spinal Tap
Electroencephalography
Electromyography and Nerve Conduction Studies
Electromyography
Nerve conduction studies
Evoked Responses
Myelography
Biopsy
Muscle and nerve
Skin
Echoencephalography
Genetic Testing
Neurologic Examination
Neurologic Examination
Mental Status
Cranial Nerves
Motor Nerves
Change in muscle size
Involuntary movements
Muscle tone
Muscle strength
Sensory Nerves
Reflexes
Coordination, Balance, and Gait
Autonomic Nervous System
Blood Flow to the Brain
Autonomic Nervous System Disorders
Multiple System Atrophy (MSA)
Causes
Symptoms
Diagnosis
Treatment
End-of-life issues
Overview of the Autonomic Nervous System
Anatomy of the autonomic nervous system
Function of the autonomic nervous system
Causes
Symptoms
Diagnosis
Treatment
Autonomic Neuropathies
Causes
Symptoms
Diagnosis
Treatment
Horner Syndrome
Causes
Symptoms
Diagnosis
Treatment
Pure Autonomic Failure
Symptoms
Diagnosis
Treatment
Brain Dysfunction
Apraxia
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Brain Dysfunction Related to COVID-19
Symptoms
Early symptoms
Later symptoms
Diagnosis
Treatment
Overview of Brain Dysfunction
Causes
Symptoms
Prognosis
Brain Dysfunction by Location
Frontal Lobe Damage
Parietal Lobe Damage
Temporal Lobe Damage
Occipital Lobe Damage
Limbic Lobe Damage
Other Locations
Aphasia
Causes
Types
Diagnosis
Treatment
Prognosis
Dysarthria
Causes
Symptoms
Diagnosis
Treatment
Agnosia
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Amnesia
Causes
Symptoms
Diagnosis
Treatment
Transient Global Amnesia
Causes
Symptoms
Diagnosis
Treatment
Wernicke-Korsakoff Syndrome
Symptoms
Diagnosis
Treatment
Brain Infections
Overview of Brain Infections
Encephalitis
Types of Encephalitis
Epidemic encephalitis
Sporadic encephalitis
Reactivation of a previous infection
Autoimmune encephalitis
COVID-19 encephalitis
Symptoms
Diagnosis
Treatment
Progressive Multifocal Leukoencephalopathy (PML)
Symptoms
Diagnosis
Treatment
Abscess of the Brain
Causes
Symptoms
Diagnosis
Treatment
Intracranial Epidural Abscess and Subdural Empyema
Causes
Symptoms
Diagnosis
Treatment
Parasitic Brain Infections
Neurocysticercosis
Other Infections
Rabies
Causes
Symptoms
Diagnosis
Prevention
Before an animal bite
After an animal bite
Treatment
More Information
Coma and Impaired Consciousness
Brain Herniation
Symptoms
Diagnosis
Treatment
Immediate treatment
Treatment to control breathing
Treatment of increased pressure within the skull
Stupor and Coma
Control of consciousness
Levels of impaired consciousness
Causes
Disorders
Substances
Mental health disorders and stress
Older age
Symptoms
Diagnosis
Physical examination
Neurologic examination
Laboratory tests
Other tests
Treatment
Immediate treatment
Treatment of the cause
Treatment to control breathing
Treatment of increased pressure within the skull
Long-term care
Prognosis
Essentials for Older Adults: Coma and Stupor
Consciousness
Vegetative State
Causes
Symptoms
Diagnosis
Treatment
Long-term care
Other issues
Prognosis
Minimally Conscious State
Symptoms
Diagnosis
Treatment
Long-term care
Other treatments
Prognosis
Locked-In Syndrome
Symptoms
Diagnosis
Treatment
Long-term care
Communication training
Other issues
Prognosis
Brain Death
Diagnosis
Optional additional tests
Prognosis
Cranial Nerve Disorders
Third Cranial Nerve (Oculomotor Nerve) Palsy
Symptoms
Diagnosis
Treatment
Fourth Cranial Nerve (Trochlear Nerve) Palsy
Causes
Symptoms
Diagnosis
Treatment
Sixth Cranial Nerve (Abducens Nerve) Palsy
Symptoms
Diagnosis
Treatment
Overview of the Cranial Nerves
Causes
Symptoms
Diagnosis
Treatment
Internuclear Ophthalmoplegia
Conjugate Gaze Palsies
Horizontal gaze palsy
Vertical gaze palsy
Trigeminal Neuralgia
Symptoms
Diagnosis
Treatment
Bell Palsy
Symptoms
Diagnosis
Treatment
Prognosis
Hemifacial Spasm
Symptoms
Diagnosis
Treatment
Glossopharyngeal Neuralgia
Causes
Symptoms
Diagnosis
Treatment
Hypoglossal Nerve Disorders
Causes
Symptoms
Diagnosis
Treatment
Craniocervical Junction Disorders
Craniocervical Junction Disorders
Causes
Present at birth
Acquired
Symptoms
Diagnosis
Treatment
Delirium and Dementia
Chronic Traumatic Encephalopathy (CTE)
Symptoms
Diagnosis
Treatment
Safety and supportive measures
Other measures
Care for caregivers
End-of-life issues
More Information
Overview of Delirium and Dementia
Delirium
Causes
Hospitalization
Surgery
Drug use
Withdrawal
Disorders
Poisons
Symptoms
Diagnosis
Medical history
Physical examination
Mental status testing
Testing
Treatment
Treatment of the cause
General measures
Management of agitation
Prognosis
Dementia
Causes
Common causes of dementia
Other disorders that can cause dementia
Reversible or treatable causes of dementias
Other disorders
Medications
Symptoms
Progression of dementia symptoms
General dementia symptoms
Early dementia symptoms
Intermediate dementia symptoms
Behavior disorders in dementia
Late (severe) dementia symptoms
Diagnosis
Medical history
Mental function testing
Physical examination
Other testing
Treatment
Safety measures
Supportive measures
Medications that may improve mental function
Medications that help control disruptive behavior
Other medications
Dietary supplements
Care for caregivers
End-of-life issues
More Information
Alzheimer Disease
Causes
Changes in the brain
Symptoms
Early in Alzheimer disease
Later in Alzheimer disease
Behavior disorders in Alzheimer disease
Progression of Alzheimer disease
Diagnosis
Diagnosis of dementia
Diagnosis of Alzheimer disease
Treatment
Safety and supportive measures
Medications
Care for caregivers
Long-term care
End-of-life issues
Prevention
More Information
Vascular Dementia
Types of vascular dementia
Causes
Symptoms
Diagnosis
Diagnosis of dementia
Diagnosis of vascular dementia
Treatment
Safety and supportive measures
Management of conditions that increase risk
Medications
Care for caregivers
End-of-life issues
More Information
Dementia With Lewy Bodies and Parkinson Disease Dementia
Changes in the brain
Symptoms
Dementia with Lewy bodies
Parkinson disease dementia
Diagnosis
Diagnosis of dementia
Diagnosis of dementia with Lewy bodies and Parkinson disease dementia
Treatment
Safety and supportive measures
Medications
Care for caregivers
End-of-life issues
More Information
Frontotemporal Dementia
Symptoms
Changes in personality and behavior
Problems with language
Diagnosis
Diagnosis of dementia
Diagnosis of frontotemporal dementia
Treatment
Safety and supportive measures
Care for caregivers
End-of-life issues
More Information
Normal Pressure Hydrocephalus
Symptoms
Diagnosis
Diagnosis of dementia
Diagnosis of normal pressure hydrocephalus
Treatment
Safety and supportive measures
Care for caregivers
More Information
Headaches
Short-Lasting Unilateral Neuralgiform Headache With Conjunctival Injection and Tearing (SUNCT)
Treatment
Medication Overuse Headache
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Overview of Headache
Causes
Common headaches
Less common headaches
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Essentials for Older Adults
Key Points
Tension-Type Headaches
Causes
Symptoms
Diagnosis
Treatment
Migraines
Causes
Symptoms
Diagnosis
Treatment
Medications
Prevention
Cluster Headaches
Symptoms
Diagnosis
Treatment
Stopping cluster headaches as soon as they start
Preventing cluster headaches
Idiopathic Intracranial Hypertension
Causes
Symptoms
Diagnosis
Treatment
Reduction of pressure within the skull
Preserving vision
Weight-loss surgery
Low-Pressure Headache
Diagnosis
Treatment
Meningitis
Introduction to Meningitis
Symptoms
Diagnosis
Treatment
Acute Bacterial Meningitis
Complications
Causes
Age
Route of entry
Strength of the immune system
Symptoms
Diagnosis
Tests
Treatment
Treatment of complications
Prognosis
Prevention
Meningococcal meningitis
Meningitis due to
Streptococcus pneumoniae
Meningitis due to
Haemophilus influenzae
Prevention after exposure to meningitis
Subacute and Chronic Meningitis
Causes
Symptoms
Diagnosis
Analysis of cerebrospinal fluid
Other tests
Treatment
Prognosis
Viral Meningitis
Causes
Transmission of viral meningitis
Symptoms
Diagnosis
Treatment
Prognosis
Noninfectious Meningitis
Causes
Symptoms
Diagnosis
Treatment
Recurrent Meningitis
Bacteria
Viruses
Other causes
Movement Disorders
Cervical Dystonia
Symptoms
Diagnosis
Treatment
Medications
Surgery
Overview of Movement Disorders
Classification
Myoclonus
Causes
Symptoms
Diagnosis
Treatment
Tremor
Types of Tremors
Physiologic tremor
Essential tremor
Resting tremor
Intention tremor
Postural tremor
Complex tremor
Causes
Evaluation
Warning signs
When to see a doctor
What a doctor does
Testing
Treatment
Physiologic tremor
Essential tremor
Intention tremors
Deep brain stimulation
Essentials for Older Adults
Key Points
Parkinson Disease (PD)
Changes inside the brain
Causes
Symptoms
Diagnosis
Physical examination
Tests
Treatment
General measures
Levodopa/carbidopa
Other medications
Deep brain stimulation
Other procedures
Stem cells
Treatment of mental symptoms
Caregiver and end-of-life issues
More Information
Parkinsonism
Causes
Symptoms
Diagnosis
Treatment
Progressive Supranuclear Palsy (PSP)
Symptoms
Diagnosis
Treatment
Chorea, Athetosis, and Hemiballismus
Causes
Symptoms
Diagnosis
Treatment
Huntington Disease
Symptoms
Diagnosis
Treatment
More Information
Dystonias
Causes
Types and Symptoms
Focal and segmental dystonias
Generalized dystonias
Diagnosis
Treatment
Coordination Disorders
Causes
Symptoms
Friedreich ataxia
Spinocerebellar ataxias
Diagnosis
Treatment
Fragile X–Associated Tremor/Ataxia Syndrome
Symptoms
Diagnosis
Treatment
More Information
Multiple Sclerosis (MS) and Related Disorders
Neuromyelitis Optica Spectrum Disorder (NMOSD)
Symptoms
Diagnosis
Treatment
Overview of Demyelinating Disorders
Causes
Multiple Sclerosis (MS)
Causes
Symptoms
Patterns of multiple sclerosis
Early symptoms of multiple sclerosis
Later symptoms of multiple sclerosis
Diagnosis
Additional testing
Treatment
Steroids
Disease-modifying therapies
Other treatments
Rehabilitative care and symptom control
General measures
Prognosis
More Information
Other Primary Demyelinating Diseases
Acute Disseminated Encephalomyelitis (ADEM)
Symptoms
Diagnosis
Treatment
Adrenoleukodystrophy and Adrenomyeloneuropathy
Leber Hereditary Optic Neuropathy
Pain
Neuropathic Pain
Symptoms
Diagnosis
Treatment
Medications
Physical and occupational therapy
Other treatments
Complex Regional Pain Syndrome
Symptoms
Diagnosis
Treatment
Chronic Widespread Pain
Symptoms
Diagnosis
Treatment
Medications
Physical or occupational therapy
Complementary and integrative medicine
Counseling and behavioral techniques
Interventional pain management techniques
Pain rehabilitation programs
Overview of Pain
Pain pathways
Acute versus chronic pain
Causes of Pain
Treatment of Pain
Nonopioid Pain Relievers
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)
Acetaminophen
Opioid Pain Relievers
Side effects of opioids
Administration of opioids
Problems with use of opioids
Adjuvant Analgesics
Antidepressants
Antiseizure medications
Anesthetics
Other medications
Nonmedication-Related Pain Treatments
Evaluation of Pain
Chronic pain
Peripheral Nerve and Related Disorders
Isaacs Syndrome
Symptoms
Diagnosis
Treatment
Stiff-Person Syndrome
Symptoms
Diagnosis
Treatment
Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)
Symptoms
Diagnosis
Treatment
Charcot-Marie-Tooth Disease
Symptoms
Diagnosis
Treatment
Hereditary Neuropathy With Liability to Pressure Palsies (HNPP)
Symptoms
Diagnosis
Treatment
Myasthenia Gravis
Neonatal myasthenia
Symptoms
Myasthenia crisis
Diagnosis
Treatment
Medications to help improve strength quickly
Treatments to suppress the autoimmune reaction
Other treatments
Eaton-Lambert Syndrome
Symptoms
Diagnosis
Treatment
Spinal Muscular Atrophies (SMAs)
Symptoms
Diagnosis
Treatment
Nerve Root Disorders
Causes
Symptoms
Diagnosis
Treatment
Polyneuropathy
Causes
Symptoms
Diagnosis
Treatment
Guillain-Barré Syndrome (GBS)
Symptoms
Diagnosis
Treatment
Supportive care
Immune globulin or plasma exchange
Other treatments
Prognosis
Overview of the Peripheral Nervous System
Causes
Disorders that may resemble peripheral nerve disorders
Diagnosis
Treatment
Amyotrophic Lateral Sclerosis (ALS) and Other Motor Neuron Diseases (MNDs)
Symptoms
Amyotrophic lateral sclerosis (Lou Gehrig disease)
Primary lateral sclerosis and progressive pseudobulbar palsy
Progressive muscular atrophy
Progressive bulbar palsy
Diagnosis
Treatment
Overview of Neuromuscular Junction Disorders
Plexus Disorders
Causes
Symptoms
Diagnosis
Treatment
Thoracic Outlet Syndromes (TOS)
Symptoms
Diagnosis
Treatment
Mononeuropathy
Causes
Symptoms
Carpal tunnel syndrome
Peroneal nerve palsy
Radial nerve palsy
Ulnar nerve palsy
Diagnosis
Treatment
Multiple Mononeuropathy
Hereditary Neuropathies
Prion Diseases
Prion Disease Associated With Diarrhea and Autonomic Neuropathy
Overview of Prion Diseases
Sporadic prion diseases
Familial prion diseases
Acquired prion diseases
Treatment
Prevention
Creutzfeldt-Jakob Disease (CJD)
Variant CJD
CJD acquired during a medical procedure
Symptoms
Diagnosis
Treatment
Prevention
More Information
Fatal Insomnia
Symptoms
Diagnosis
Treatment
Gerstmann-Sträussler-Scheinker Disease (GSS)
Kuru
Variably Protease-Sensitive Prionopathy (VPSPr)
Seizure Disorders
Seizure Disorders
Types of seizures
Causes
Symptoms
Focal-onset seizures
Generalized-onset seizures
Status epilepticus
Dravet syndrome
Symptoms after a seizure
Complications
Diagnosis
History and physical examination
Testing
Treatment
General measures
Antiseizure medications
Emergency treatment
Surgery
Stimulation of the vagus nerve
Stimulation of the brain
Prognosis
Sleep Disorders
Snoring
Causes
Sleep-disordered breathing
Complications
Risk factors
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
General measures
Oral appliances
Continuous positive airway pressure (CPAP)
Surgery
Key Points
Overview of Sleep
The sleep cycle
Sleep disorders
Essentials for Older Adults
Age-related changes
Disorders in older adults
Medications in older adults
Older adults and napping
Measures to improve sleep in older adults
Insomnia and Excessive Daytime Sleepiness (EDS)
Causes
Common causes
Less common causes
Evaluation
Warning signs
When to see a doctor
What the doctor does
Testing
Treatment
Sleep hygiene
Cognitive-behavioral therapy
Prescription sleep aids
Over-the-counter sleep aids
Antidepressants
Essentials for Older Adults
Key Points
Circadian Rhythm Sleep Disorders
Causes
Symptoms
Diagnosis
Treatment
Medications
Narcolepsy
Symptoms
Excessive daytime sleepiness
Cataplexy
Sleep paralysis
Hallucinations
Disturbances in nighttime sleep
Complications
Diagnosis
Treatment
Periodic Limb Movement Disorder (PLMD) and Restless Legs Syndrome (RLS)
Symptoms
Symptoms of periodic limb movement disorder
Symptoms of restless legs syndrome
Diagnosis
Treatment
Parasomnias
Night terrors
Nightmares
Sleepwalking (somnambulism)
Rapid eye movement sleep behavior disorder
Sleep-related leg cramps
Sleep Disorders in Dementia
Treatment
Spinal Cord Disorders
Cauda Equina Syndrome
Causes
Symptoms
Diagnosis
Treatment
Autonomic Dysreflexia of the Spinal Cord
Symptoms
Diagnosis
Treatment
Epidural Abscess in the Spine
Symptoms
Diagnosis
Treatment
Overview of Spinal Cord Disorders
Anatomy
Causes
Outside the spinal cord
Inside the spinal cord
Symptoms
Diagnosis
Treatment
Rehabilitation
Compression of the Spinal Cord
Causes
Symptoms
Diagnosis
Treatment
Cervical Spondylosis
Symptoms
Diagnosis
Treatment
Syrinx of the Spinal Cord or Brain Stem
Symptoms
Diagnosis
Treatment
Hereditary Spastic Paraplegia
Symptoms
Diagnosis
Treatment
Acute Transverse Myelitis
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Blockage of the Blood Supply to the Spinal Cord
Symptoms
Diagnosis
Treatment
Subacute Combined Degeneration
Symptoms
Diagnosis
Treatment
HTLV-1–Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP)
Symptoms
Diagnosis
Treatment
Stroke
Intracerebral Hemorrhage
Causes
Symptoms
Diagnosis
Treatment
Prognosis
Subarachnoid Hemorrhage
Causes
Symptoms
Diagnosis
Treatment
Procedures to treat aneurysms
Prognosis
Brain Arteriovenous Malformations
Diagnosis
Treatment
Brain Aneurysms
Causes
Symptoms
Diagnosis
Treatment
Overview of Stroke
Types
Risk factors for stroke
Symptoms
Warning symptoms of stroke
Other symptoms
Effects of stroke
Complications of stroke
Diagnosis
Treatment
Rehabilitation
Prognosis
End-of-Life Issues
Prevention
Managing risk factors
Antiplatelet medications
Anticoagulants
Transient Ischemic Attacks
Causes
Risk factors
Symptoms
Diagnosis
Treatment
Medications
Surgery
Angioplasty and stent placement
Ischemic Stroke
Causes
Common causes
Cryptogenic stroke
Embolic stroke
Lacunar infarction
Large-vessel atherosclerosis
Other causes
Risk factors
Symptoms
Complications of stroke
Diagnosis
Tests to identify the cause
Treatment
Thrombolytic (fibrinolytic) medications
Mechanical thrombectomy
Antiplatelet medications and anticoagulants
Carotid artery surgery
Carotid artery angioplasty and stenting
Long-term treatment of strokes
Prognosis
Overview of Hemorrhagic Stroke
