Neurological Disorders Part 1

Vocabulary flashcards derived from lecture notes on neurological disorders.

Wernicke’s Area

An area in the dominant hemisphere responsible for language comprehension.

Cranial Nerves

Twelve pairs of nerves that originate in the brain and control motor and sensory functions of the head and neck.

Paresthesia

Abnormal sensations such as tingling or numbness, often seen in neuropathies.

Paresis

Weakness or partial loss of muscle strength.

Delirium

An acute, transient state of confusion often due to underlying medical issues.

Dementia

A progressive decline in cognitive function that interferes with daily living.

Seizure

A sudden, transient occurrence of signs or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.

Generalized Onset Seizures

Seizures that affect the entire brain and include types like tonic-clonic and absence seizures.

Focal Onset Seizures

Seizures that affect just one part of the brain, which may or may not impair consciousness.

Dizziness

A sensation of unsteadiness or feeling of movement within the head.

Vertigo

A sensation of rotation or movement of the patient or their surroundings.

Temporal Arteritis

Inflammation of the temporal arteries that can lead to severe headaches and vision loss.

Headache

Pain in any region of the head, which may be classified into primary or secondary types.

Cluster Headache

A severe unilateral headache characterized by grouping of attacks and often occurring at night.

Migraine

A recurring headache characterized by unilateral location, pulsating quality, and associated symptoms like nausea.

Motor Pathways

Neurological pathways that control voluntary movements, including corticospinal and extrapyramidal tracts.

Cerebellum

A structure in the brain that coordinates voluntary movements and maintains balance.

Bell's Palsy

Acute, unilateral facial nerve (cranial nerve VII) paralysis caused by inflammation or compression. It manifests as sudden weakness or paralysis affecting one side of the face, including inability to close the eye, smile, or raise the eyebrow. Typically temporary.

Trigeminal Neuralgia

A chronic pain condition affecting the trigeminal nerve (cranial nerve V), causing sudden, severe, shock-like facial pain, usually on one side of the face. Pain attacks are often triggered by touch, chewing, talking, or brushing teeth.

Alzheimer's Disease

The most common cause of dementia, a progressive neurodegenerative disease characterized by memory loss, cognitive decline, and behavioral changes. It involves the accumulation of amyloid plaques and neurofibrillary tangles in the brain, leading to neuronal damage and brain atrophy.

Transient Ischemic Attack (TIA)

Often called a "mini-stroke," a TIA is a temporary episode of neurological dysfunction caused by a brief interruption of blood flow to the brain, spinal cord, or retina, with no acute infarction. Symptoms are similar to a stroke but typically resolve within minutes to 24 hours. TIAs are a warning sign for future strokes.

Stroke

A medical emergency where poor blood flow to the brain results in brain cell death. Divided into two main types:
- Ischemic Stroke: Accounts for ~87% of strokes, caused by a blockage in a blood vessel supplying the brain (thrombosis or embolism).
- Hemorrhagic Stroke: Caused by bleeding into the brain tissue or surrounding spaces, often due to ruptured blood vessels (e.g., aneurysm).
Symptoms include sudden weakness, numbness, difficulty speaking, confusion, or vision loss.

National Institutes of Health Stroke Scale (NIHSS)

A systematic assessment tool used to quantify the severity of neurological deficits caused by a stroke. It evaluates 11 different items, including level of consciousness, visual fields, facial palsy, motor arm, motor leg, limb ataxia, sensory deficits, best language, dysarthria, and inattention. Scores range from 0 (no stroke symptoms) to 42 (severe stroke).

Parkinson's Disease

A progressive neurodegenerative disorder primarily affecting dopamine-producing neurons in the substantia nigra of the brain. Characterized by motor symptoms such as:
- Tremor (often "pill-rolling" at rest)
- Bradykinesia (slowness of movement)
- Rigidity (stiffness of the limbs and trunk)
- Postural instability (impaired balance and coordination)
Non-motor symptoms include cognitive changes, sleep problems, and mood disorders.

General Characteristics and Causes of Seizures

Seizures are caused by abnormal electrical activity in the brain. They can manifest in various ways, including:
- Motor symptoms: Uncontrolled jerking movements (convulsions), muscle rigidity, or limpness.
- Sensory symptoms: Tingling, numbness, visual disturbances, or altered smells.
- Autonomic symptoms: Changes in heart rate, breathing, or bowel/bladder control.
- Cognitive/Psychic symptoms: Confusion, déjí vu, or fear.
Causes include epilepsy, head injury, stroke, infection, brain tumors, electrolyte imbalances, and drug withdrawal.

Clinical Presentation and Importance of Temporal Arteritis

Also known as Giant Cell Arteritis, it's an inflammatory disease of large and medium-sized arteries, often affecting temporal arteries. Key symptoms include:
- New-onset severe headache (often temporal)
- Scalp tenderness
- Jaw claudication (pain when chewing)
- Constitutional symptoms (fever, weight loss, fatigue)
- Risk of permanent vision loss due to ophthalmic artery involvement.
Prompt diagnosis and corticosteroid treatment are crucial to prevent irreversible blindness.

Amyotrophic Lateral Sclerosis (ALS)

A progressive neurodegenerative disease that affects motor neurons in the brain and spinal cord. It leads to the degeneration of upper and lower motor neurons, resulting in:
- Progressive muscle weakness
- Muscle atrophy (wasting)
- Fasciculations (muscle twitching)
- Difficulty speaking (dysarthria), swallowing (dysphagia), and eventually breathing.
Sensation and cognitive function are typically preserved.

Multiple Sclerosis (MS)

A chronic, autoimmune disease of the central nervous system where the immune system attacks the myelin sheath, the protective covering of nerve fibers. This demyelination disrupts nerve signal transmission, leading to a wide range of neurological symptoms that can vary significantly among individuals, including:
- Fatigue
- Numbness or weakness in limbs
- Vision problems (e.g., optic neuritis)
- Difficulty with balance and coordination
- Cognitive impairment
MS often presents with relapsing-remitting patterns but can also be progressive.

Types and Associated Symptoms of Vertigo

Vertigo is a type of dizziness characterized by a false sensation of self-motion or motion of one's surroundings. It can be classified into:
- Peripheral Vertigo: Caused by problems in the inner ear or vestibular nerve (e.g., Benign Paroxysmal Positional Vertigo [BPPV], Meniere's disease, vestibular neuritis). Often accompanied by hearing loss, tinnitus, or ear fullness.
- Central Vertigo: Caused by problems in the brainstem or cerebellum (e.g., stroke, MS, tumor). Often associated with severe neurological signs like double vision, weakness, or ataxia, and usually no hearing symptoms.

Myasthenia Gravis

An autoimmune neuromuscular disorder characterized by fluctuating muscle weakness and fatigue. It occurs when the immune system mistakenly attacks acetylcholine receptors at the neuromuscular junction, preventing nerve impulses from effectively stimulating muscle contraction. Symptoms often worsen with activity and improve with rest, commonly affecting:
- Eye muscles (ptosis, double vision)
- Facial and throat muscles (difficulty speaking, swallowing)
- Limb and respiratory muscles

Mini-Mental Status Exam (MMSE)

A widely used, 30-point questionnaire to screen for cognitive impairment, commonly used in suspected dementia. It assesses various cognitive domains, including:
- Orientation (time and place)
- Attention and calculation
- Recall
- Language (naming, repetition, comprehension, writing)
- Visuospatial skills (copying a drawing)
A score below 24 typically suggests cognitive impairment, with lower scores indicating greater severity.

Encephalitis

Inflammation of the brain parenchyma, most commonly caused by a viral infection (e.g., herpes simplex virus, arboviruses).
Symptoms include:
- Fever
- Headache
- Altered mental status (confusion, disorientation, personality changes)
- Seizures
- Focal neurological deficits

Meningitis

Inflammation of the meninges, the protective membranes surrounding the brain and spinal cord, typically caused by bacterial or viral infection.
Classic symptoms include:
- Severe headache
- Fever
- Stiff neck (nuchal rigidity)
- Photophobia (sensitivity to light)
- Altered mental status
Bacterial meningitis is a medical emergency requiring urgent antibiotic treatment.