Download Pathophysiology Chapter 23 - Chronic Neurologic

Pathophysiology Chapter 23 - Chronic Neurologic Disorders
I. Review of the Nervous System
A. Responses
1. involuntary - reflexes - ans
2. voluntary - somatic nervous system
B. Protection for the brain
1. skull
2. meninges
a. dura mater
-tough outer layer
-subdural space
b. arachnoid mater
-middle layer
-weblike
-subarachnoid space - contains CSF, arteries, veins
-arachnoid villi - absorb CSF into venous blood
c. pia mater
-inner delicate covering
-adheres to brain tissue
-many capillaries
3. CSF - cerebrospinal fluid
a. cushions
b. clear fluid
c. definite concentrations of electrolytes, glucose, protein
d. formed constantly in ventricles of brain
e. circulates around brain and spinal cord
f. = amt. must be produced/reabsorbed at same rate
C. Blood-brain barrier and blood-CSF barrier
1. blood-brain barrier
a. impermeable capillary walls
b. limits passage of potentially damaging materials from blood into brain
c. controls balance of electrolytes, glucose, protein in CSF
2. barrier in place in ventricles for CSF/venous blood exchange
D. Functional areas
1. cerebral hemispheres - 2 a. connected by corpus callosum - bundle of nerve fibers
b. gyri
c. sulci
d. longitudinal fissure
e. cerebral cortex - surface
-gray matter - nerve cell bodies
-white matter below - myelinated nerve fibers
-basal nuclei - islands of gray matter inside white matter (voluntary motor
skills)
f. each cerebral hemisphere divided into 4 major lobes
-frontal
-prefrontal area - intellectual function and personality
-premotor cortex - skilled movements
-motor cortex - voluntary movements
-Broca's area - speech
-pyramidal (corticospinal) tracts - 2 major voluntary motor tracts (bundles)
-extend from cortex down medulla on ventral surface continuing to
descend to spinal cord
-parietal
-somatosensory area - sensation (touch, pain, etc.)
-occipital
-visual cortex - vision
-temporal
-auditory cortex - hearing
-olfactory cortex - smell
-Wernicke's area - comprehension of speech; memory
g. dominant hemisphere (usually left) - language, mathematical, problem
solving, logical reasoning abilities
h. other hemisphere (usually right) - artistic abilities, creativity, spatial
relationships, and emotional and behavioral characteristics
2. diencephalon
a. central portion of brain
b. surrounded by hemispheres
c. contains thalamus and hypothalamus
d. thalamus
-incoming sensory sorting and relay center
e. hypothalamus
-part of limbic system
-maintaining homeostasis (body temp., appetite, pain, sleep, thirst, etc.)
-controlling ans and lots of endocrine system
-key to stress response
-regulates pituitary gland
-regulates adrenal glands
f. limbic system
-primitive brain structures on top of brain stem
-emotional responses (survival responses, fear, anger, etc.)
-sex drive (libido)
-pleasure center
-2 important structures
- amygdala - what memories are stored and where stored
-hippocampus - sends long-term memories to be stored and retrieves
them when needed
3. brainstem - inferior portion of brain
-contains pons, medulla oblongata, midbrain, reticular formation
-connecting link to spinal cord
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-pons - bundle of fibers - involved in breathing
-medulla oblongata - fiber tract area connecting to spinal cord
-regulates respiration, cough reflex, swallowing, vomiting, blood pressure,
heart rate, etc.
-site of crossover (decussation) of majority of pyramidal (corticospinal)
tracts
-midbrain
-reflex centers involved in vision and hearing, eye movement, body
movement
-contain large number of dopamine producing neurons
-reticular formation
-motor control of visceral organs
-arousal or awareness of cerebral cortex
-decides which incoming sensory impulses brain ignores/notices
4. cerebellum
-coordinate movement
-maintain posture and equilibrium
E. Blood supply to the brain
1. provided by carotid and vertebral arteries
2. anastomoses - union of bv forming a sinus (sac)
3. pressoreceptors
-protect brain from damage by abnormal bp
4. chemoreceptors
-protect brain from abnormal pH and oxygen levels
5. blood returned to jugular veins/heart by means dural sinuses
F. Cranial nerves
a. 12 pairs
b. originate from brainstem/pass through foramina (holes) in skull to head and
neck
G. Spinal Cord and Peripheral nerves
1. protection
a. vertebral column
b. meninges
c. CSF
2. spinal cord begins at medulla oblongata and ends at L1
3. L2 on - bundle of nerve roots - cauda equina
4. spinal tap (lumbar puncture)
-subarachnoid space between L3 and L4
5. composition of cord
a. white matter - nerve fibers - surrounds gray matter
b. gray matter - nerve cell bodies (motor neurons)
c. peripheral nerves leave spinal cord to all parts of body
H. Spinal nerves
1. 31 pairs
2. connected to spinal cord by 2 short roots
3. plexuses
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a. interlacing network of nerve fibers (or blood vessels)
b. four
-cervical, brachial, lumbar, sacral
I. Reflexes
1. automatic, rapid, involuntary responses to stimulus
2. pathway
a. sensory stimulus from receptor
b. conducted along afferent nerve fiber to brain
c. stimulus assessed
d. efferent impulse sent along peripheral nerve
e. response
J. Neurons and conduction of impulses
1. neurons
a. nonmitotic cells that conduct impulses throughout CNS and PNS
b. require glucose and oxygen for metabolism
c. cytoplasmic extensions
-dendrites receive impulses and send toward cell body
- axons send impulses away from cell body
d. myelin sheath - covering for many nerve fibers
-insulates fiber
-speeds up rate of conduction
-formed by cell membrane of Schwann cells
-nucleus and cytoplasm form neurilemma or sheath of Schwann around
myelin
-nodes of Ranvier - gaps between Schwann cells
e. glial cells - support/protect neurons
-Astroglia - astrocytes
-Oligodendroglia
-Microglia
-Ependymal cells
2. regeneration of neurons
a. nonmitotic
b. cell body damaged - entire neuron dies
c. axons may regenerate if cell body viable
d. new growth not always correct/appropriate
3. conduction of impulses
a. inside of cell negative, outside positive - membrane potential
b. sodium/potassium pump - 3 Na+ ions out/2 K+ ions in - maintains membrane
potential
c. stimulus occurs
-increases permeability allowing Na+ to flow into cell
-depolarizes cell membrane
-action potential generated
-impulse travels along membrane
-repolarization occurs as K+ ions move out
-membrane potential restored
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-Na+/K+ pump returns ions to proper amount to maintain membrane
potential
-myelinated nerve fibers - impulses travel much faster than unmyelinated
d. synapses
-connection between 2 or more neurons or neuron and
effector site
-may have multiple synapses per neuron
4. Synapses and chemical neurotransmitters
a. a typical synapse
-axon terminal of presynaptic neuron
-synaptic vesicle containing neurotransmitter
-synaptic cleft - fluid filled gap
-receptor of postsynaptic neuron
b. process of stimulus (nerve impulse)
-stimulus reaches axon terminal
-synaptic vesicles release chemical (neurotransmitter) into synaptic cleft
-neurotransmitter flows across synaptic cleft to receptors in postsynaptic
membrane
-stimulus created
-neurotransmitter inactivated by enzymes or taken up by presynaptic axon
-prevents further stimulation
c. examples of neurotransmitters
-acetycholine (ACh), catecholamines, norepinephrine (adrenaline),
epinephrine, serotonin, histamine, and gamma-aminobutyric acid (GABA)
5. neurotransmitters play role in mental illnesses
-example: norepinephrine and dopamine - excitatory - low level leads to
depression
K. Autonomic Nervous System (ANS)
1. sympathetic and parasympathetic nervous systems
a. antagonistic effects
b. provide balance in maintaining homeostasis
2. motor and sensory innervation to smooth muscle, cardiac muscle, and glands
3. Sympathetic Nervous System - increases general level of activity in body
a. fight or flight response
b. increases breathing, heart, brain, etc.
c. neurotransmitters closely linked to drug actions
4. Parasympathetic Nervous System
a. dominates digestive system, aids in recovery of body after sympathetic
activity (has opposite effect on body from sympathetic ns)
b. ganglia scattered - located close to target organ and neurotransmitter
II. Congenital Neurologic Disorders
A. Hydrocephalus
1. pathophysiology
a. excess csf within skull (water on the brain)
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b. caused by stenosis, neural tube defect, impaired absorption of csf, atresia
(absence of a canal or opening), tumors, infection, scar tissue, thickened
arachnoid membrane
c. many neonates have a myelomeningocele (Arnold-Chiari malformation)
-herniation of sc, nerves, meninges, and csf
d. compresses brain tissue/blood vessels
e. varying amounts of brain damage result
2. etiology (cause/origin) - listed above
3. signs and symptoms
a. neonates/young infants - bulging fontanels and enlarged head
b. dilated scalp veins
c. "sunset sign"
d. slow pupil response to light
e. lethargy and irritability
f. difficult to feed
g. high pitched cry when moved
4. diagnostic tests
-MRI or CT scan
5. treatment
-surgery to place shunt
B. Spina Bifida
-neural tube defects (in embryo - hollow dorsal tube that becomes brain and
spinal cord).
1. pathophysiology
a. failure of spinous process on vertebra to fuse
b. allows herniation of meninges and spinal cord
c. usually occurs in lumbar area
2. 3 types of spina bifida
a. spina bifida occulta
-spinous process does not fuse
-no herniation
b. meningocele
-spinous process does not fuse
-herniation of meninges and csf
-sac formed on outside of lumbar area
-transillumination
-no neurologic impairment
c. myelomeningocele - discussed above
3. diagnostic tests
a. AFP - alpha-fetoprotein in maternal blood
b. amniocentesis
c. ultrasound
4. etiology
a. genetic
b. environmental
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-exposure to radiation, gestational diabetes, deficits of vitamin A or folic acid
during pregnancy
5. signs and symptoms
a. meningocele or myelomeningocele visible
b. motor function at/below herniation impaired
c. some muscle weakness or paralysis
d. impaired bladder and bowel control
6. treatment
a. surgical repair of sac
b. physical therapy
C. Cerebral Palsy
1. pathophysiology
a. some degree of motor disability caused by brain damage during perinatal
pd.
b. damage caused by malformation, mechanical trauma, hypoxia,
hemorrhage, hypoglycemia, hyperbilirubinemia, kernicterus - bilirubin
crosses blood- brain barrier and damages neurons
c. result: necrosis and atrophy of brain tissue
2. etiology - listed above
3. signs and symptoms
a. classified 2 ways
-on basis of area affected - quadriplegia or diplegia
-on basis of resulting motor disability
-spastic paralysis - motor cortex or pyramidal tracts - hyperreflexia
(excessive reflex response)
-dyskinetic - basal nuclei, extrapyramidal tracts, or cranial nerves - loss of
motor control/coordination and choreiform movement
-ataxic - cerebellum - gait disturbance, loss of balance
-mixed - all of the above - some of each
b. other areas of dysfunction
-intellectual function
-communication and speech
-seizures
-vision (astigmatism, strabismus)
4. treatment
a. speech and language pathologists
b. physical therapy
c. exercise
d. braces
e. wheelchair
f. medication for seizures
III. Seizure Disorders
A. Pathophysiology
1. results from uncontrolled, spontaneous, excessive depolarization of neurons
2. causes abnormal motor or sensory activity; possible loss of consciousness
3. lower threshold of stimulation
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4. neurons can be activated by physiologic change (i.e. flashing lights)
5. duration - seconds to minutes
6. classified by location and clinical features
a. generalized seizures - multiple foci (origins) in both cerebral hemispheres
and brainstem; lose consciousness
b. partial seizures - one foci usually in cerebral cortex; might lose consciousness
c. idiopathic - no known cause
d. secondary (acquired) - identifiable cause
7. EEG - indicates location and type of seizure
8. injuries might occur
9. status epilepticus - continuous seizures without recovery of consciousness dangerous
B. Etiology
1. withdrawal from drugs and/or alcohol, hypoglycemia, ptsd., renal failure,
high fever, infection, tumor, hemorrhage in brain, etc.
2. precipitating factors (triggers)- loud noises, flashing lights, stress,
hyperventilation, excessive premenstrual fluid retention, etc.
C. Signs and Symptoms
1. generalized seizures a. absence (petit mal) seizures: brief loss of awareness, no
memory of episode
b. tonic-clonic (Grand mal) seizures - definite pattern of events
-tonic stage
-prodromal signs - nausea, depression, muscle twitching, irritability
-aura - peculiar auditory or visual sensation precedes loss of consciousness
-loss of consciousness
-strong tonic muscle contraction, flexion, extension of limbs and rigidity
in trunk
-air forced out of lungs due to diaphragm contracting - sounds like a cry jaw clenches, breathing ceases
-clonic stage
-muscles alternately contract and relax
-increased salivation
-possible loss of bowel and bladder control
-contractions cease, body goes limp - consciousness slowly returns
-postictal period - individual confused and fatigued, has aching muscles,
falls into deep sleep
- possible hypoxia, acidosis, some amnesia
- possible status epilepticus
2. partial seizures
-simple partial or focal seizures
-arise from epileptogenic focus in cortex
-repeated motor activity (jerking head or leg, tingling sensation, etc.)
-possible auditory/visual experiences
-memory and consciousness remain with reduced awareness
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-complex partial, temporal lobe, or psychomotor seizures
-bizarre behavior
-repetitive but inappropriate behavior - clapping hands
-visual or auditory hallucinations
-feelings of déjà vu
-afterwards - drowsy and amnesic
D. Diagnostic Tests
1. medical history
2. EEG
3. MRI
E. Treatment
-anticonvulsant drugs possible in combination with sedatives
-complications from drugs: reduced wbc, reduced blood-clotting ability,
sudden withdrawal may trigger more seizures with possible status epilepticus
IV. Chronic Degenerative Disorders
A. Multiple Sclerosis (MS)
1. Pathophysiology
a. progressive demyelination of neurons of brain, spinal cord, and cranial nerves
b. interferes with conduction of impulses
c. occurs in patches throughout nervous system
d. all types of neurons affected
e. no known cure
f. permanent and progressive
g. remissions and exacerbations
2.. Etiology
a. onset - between 20-40 yrs. of age
b. more common in women and people of European descent
c. autoimmune and possible viral infection
d. genetic, immunologic, and environmental components
3.. Signs and symptoms
a. manifestations determined by areas of demyelination
b blurred vision, leg weakness, double vision (diplopia), spot in field of
vision (scotoma), dysarthria (poor articulation), paresthesias, numbness,
burning, tingling, depression, euphoria
c. complications - respiratory infections, decubitus ulcers, contractures
4.. Diagnostic tests
a. patient history
b. physical exam
c. MRI
d. spinal tap (elevated protein, gamma globulin, lymphocytes)
5. Treatment
a. glucocorticoids, interferon
b. muscle relaxants
c. avoid excessive fatigue, stress, injury, infection
d. physical therapy/exercise
e. speech/language pathologists
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B. Parkinson's Disease
1. pathophysiology
a. progressive degenerative disorder
b. motor neurons affected
c. located in basal nuclei outside of pyramidal tracts (specifically in substantia
nigra)
d. fewer neurons secrete dopamine - leads to imbalance between excitation and
inhibition in basal nuclei
e. affects movement and posture due to increasing muscle tone and activity
f. resting tremors, muscular rigidity, difficulty in initiating movement, and
postural instability
g. possible dementia (b/c of reduced # of cortical neurons)
2. etiology
a. primary or idiopathic Parkinson's
b. secondary parkinsonism - encephalitis, trauma, vascular disease, certain
drugs
3. signs and symptoms
a. fatigue
b. muscle weakness/aching
c. decreased flexibility
d. hand tremors
e. increased muscle rigidity
f. propulsive gait
g. flat voice
h. difficulty in chewing/swallowing
i. drooling
j. face becomes like a mask
k. bladder/bowel issues
l. respiratory infections
m. dementia
4. treatment
a. dopamine replacement therapy, medications
b. speech/language pathologist
c. exercise/physical therapy
C. Amyotrophic Lateral Sclerosis (ALS) - Lou Gehrig's disease
1. Pathophysiology
a. amytrophic - muscle wasting; sclerosis - hardening of lateral corticospinal
tracts
b. rapid continuous decline of motor function while cognitive function remains
okay
c. areas affected - both upper motor neurons in cerebral cortex and lower
motor neurons in brainstem and spinal cord
d. loss of upper neurons - spastic paralysis and hyperreflexia
e. loss of lower neurons - flaccid paralysis, decreased muscle tone/reflexes
f. progressive muscle weakness
g. develops usually after age 60
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2. signs and symptoms
a. weakness/atrophy in upper arms/hands
b. loss of fine motor coordination
c. stumbling/falling
d. muscle cramps
e. dysarthria
f. swallowing and respiration impaired - will need a ventilator
g. respiratory failure - 2-5 years
3. treatment
a. exercise
b. rest
c. physical and respiratory therapist, speech pathologist, nutritionist,
psychologist, social worker
D. Myasthenia Gravis
1. pathophysiology
a. autoimmune disorder
b. blocks/destroys acetylcholine receptors at synaptic cleft
-prevents further stimulation of muscle
c. women more than men
d. between 20-30 yrs. of age and over 50 for men
e. skeletal muscle weakness/rapid fatigue
f. begins with facial/ocular muscles, then arm and trunk muscles
2. diagnostic tests
a. electromyography for muscle fatigue
b. assay of serum antibodies
3. signs and symptoms
a. muscle weakness in face/eyes
- loss of spontaneous facial expressions
-drooping of face
b. fatigue
c. diplopia and ptosis impair vision
d. speech becomes nasal/monotone
e. chewing/swallowing difficulty
f. head droops
g. arms weaken
h. upper respiratory infections
i. Myasthenic crisis may occur - increase in symptoms under stress, illness, etc.
4. treatment
a. medications for improved neuromuscular transmission
-anticholinesterase drugs - prolong ACh at neuromuscular junction
b. glucocorticoids
c. plasmapheresis - removes ab from blood
E. Huntington's Disease
1. pathophysiology
a. inherited autosomal dominant trait on chromosome #4
b. manifests in midlife
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c. progressive atrophy of brain
d. degeneration of neurons in basal ganglia/frontal cortex
e. ventricles become dilated
f. depletion of GABA - inhibitory neurotransmitter
g. ACh level decreases
2. etiology - listed above
3. signs and symptoms
a. onset
-mood swings, personality changes, restlessness, rapid jerky movements in
arms/face, intellectual impairment
b. later
-progressive degeneration, rigidity and akinesia develop, more personality
changes, moodiness, dementia
4. diagnostic tests
-DNA analysis
5. Treatment
-none
V. Dementia
A. General Information
1. progressive chronic disease
2. cognitive skills impaired
a. mathematical ability and reasoning
b. language
c. logical thinking
d. judgment
e. ability to learn new information
f. motor coordination
g. short term memory
h. confusion within long term memory
i. behavioral/personality changes
3. causes
a. vascular disease (arteriosclerosis)
b. infections
c. toxins
d. genetic disorders
e. Alzheimer's
B. Alzheimer's Disease
1. general information
a. females more than males
b. progressive loss of intellectual function
c. personality changes
d. personal hygiene, relationships, work suffer
e. lack of initiative
f. repetitive behavior
g. impaired judgment, abstract thinking, problem-solving
2. pathophysiology
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a. progressive cortical atrophy
b. dilated ventricles
c. widening of sulci
d. tangles in neurons
e. senile plaques - disrupts nerve impulse transmission
f. number/distribution of plaques significant
g. deficit of ACh in brain
3. etiology
a. to date, 4 defective genes found
b. 3 of the 4 are autosomal dominant traits
4. signs and symptoms
a. onset insidious - extends over 10-20 years
b. 3 stages
-early stage
-gradual loss of memory
-lack of concentration
-behavioral changes (irritable, hostile, mood swings)
-reasoning/learning of new information impaired
-depression/anxiety
-middle stage
-cognitive function, memory, language continue to decline
-problem solving, mathematical ability and judgment poor
-apathy, indifference, confusion become more marked
-daily living becomes difficult
-wandering
-late stage
-no recognition of family
-no awareness or interest in surroundings
-incontinent
-language gone
-continual decline
5. treatment
a. nothing specific
b. medications for symptoms
c. therapists, exercise, social worker
d. daily routine important
e. moderate stimulation
f. survival range - up to 20 years - 7 years average
C. Other forms of dementia
1. vascular dementia
a. cerebrovascular disease
b. result of multiple brain infarctions
c. onset insidious - memory loss, apathy, inability to manage daily routines
2. Creutzfeldt-Jakob Disease (CJD)
a. rare and rapidly progressive
b. caused by infection by a prion (infectious protein particle - PrP)
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c. long incubation pd.
d. rapid destruction of neurons, formation of plaques, and vacuoles in
neurons (spongiform encephalopathy)
e. memory loss, behavioral changes, motor dysfunction, progressive
dementia
f. no treatment
g. linked to consumption of beef with Mad Cow Disease
3. AIDS Dementia
a. latter stages of AIDS
b. HIV virus invades brain tissue
c. loss of memory, cognitive ability, impaired motor function
d. in children with congenital infection - mental retardation/delayed motor
development
VI. Mental Disorders
A. General information
1. classified by Diagnostic and Statistical Manual of Mental Disorders (DSM)
2. defined - significant dysfunction in areas of behavior or personality interfering
with person's ability to function
3. biochemical/structural abnormalities involved
4. some - genetic component
5. stressors involved in development of disorders
6. Psychotic illness - more serious disorders
a. schizophrenia
b. delusional disorders
c. affective or mood disorders
7. anxiety/panic disorders
B. Schizophrenia
1. pathophysiology
a. variety of syndromes presented - each person unique
b. common changes
-reduced gray matter in temporal lobes
-enlarged third and lateral ventricles
-abnormal cells in hippocampus (part of limbic system)
-excessive dopamine secretion
-decreased blood flow to frontal lobes
2. etiology
a. genetic predisposition
b. brain damage in fetus
c. onset - between ages 15-25 in men
- between 25-35 in women
d. stressful events initiate onset and recurrences
3. signs and symptoms
a. grouped 2 ways
-positive (delusions, bizarre behavior)
-negative (flat emotions, decreased speech)
b. disorganized thought processes
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c. poor language skill
d. lack of appropriate association of thoughts
e. meaningless repetition of words or thoughts
f. development of "new" words
g. delusions/false beliefs and ideas
h. poor problem solving
i. brief attention span
j. hallucinations or abnormal sensory perceptions
k. social withdrawal
l. little emotion
m. lack of self-care
n. mood swings/anxious
4. treatment
a. antipsychotic drugs
-Thorazine, Prolixin, Haldol, clozapine
-many have side effects on extrapyramidal system (jerking, twitching,
tremors, grimacing, writhing movements of limbs, shuffling gait, etc.)
b. psychotherapy
c. psychosocial rehabilitation
C. Depression
1. general information
-mood disorder
-unipolar disorder - major depression
-factors - genetic, developmental, and psychosocial disorders
-bipolar
-alternating periods of depression and mania
2. pathophysiology
a. linked to deficits of excitatory neurotransmitters
-norepinephrine and serotonin in brain
b. may also develop secondary to systemic disorders
3. signs and symptoms
a. prolonged pd. of profound sadness, hopelessness, lack of joy in activities
b. lack of energy
c. loss of self-esteem and motivation
d. all of the above interfere with daily life
e. difficulty in concentration and problem-solving
f. too little/much sleep
g. loss of appetite and libido
4. treatment
a. antidepressants
-SSRIs - Prozac; SNRIs - Effexor; tricyclic antidepressants (TCAs) - Elavil;
monoamine axidase (MOA) inhibitors - Parnate
b. electroconvulsive shock therapy (ECT) - increases norepinephrine activity
D. Panic Disorder
1. general information
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a. panic attack - sudden brief episode of discomfort and anxiety
b. panic disorder - when panic attacks frequent/prolonged
2. pathophysiology
a. genetic factor
b. increased discharge of neurons - temporal lobe
c. biochemical abnormalities with neurotransmitters
-norepinephrine, serotonin, GABA
3. signs and symptoms
a. repeated episodes of intense fear/anxiety without reason
b. experience: tachycardia or palpitations, hyperventilation, sweating, nausea,
sensations of choking or smothering
c. may develop phobias
4. treatment
a. psychotherapy
b. medications: Xanax, Valium
VII. Spinal Cord Problems
A. Herniated Intervertebral Disc
1. cartilaginous discs separate vertebrae
2. herniation - protrusion of nucleus pulposus
3. places pressure on spinal nerve root/cord
B. Etiology
1. trauma
2. poor body mechanics (improper lifting)
C. signs and symptoms
1. pain in back/neck; radiates down leg(s)/arm(s)
2. numbness/tingling
3. muscle weakness
D. diagnostic tests
1. MRI
2. CT scan
3. myelography with contrast dye
E. treatment
1. bed rest
2. heat, ice, or traction
3. medications
4. surgery: laminectomy, diskectomy, chemonucleolysis, spinal fusion
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