NERVOUS SYSTEM: EXAM #3: MODULES 8.2-3 TERMS

1. APHASIA-loss of comprehension & languagea) Expressive(motor)-difficulty speaking & writing ex. Damage Broca’s area due to

strokeb) Receptive(sensory)- difficulty understanding writing & speech ex. Damage

Wernicke area due stroke2. Ataxia- lack co-ordination of movement3. Concussion-a minor traumatic brain injury4. Dysarthria- lack control over muscles of speech5. Transient ischemic attack (TIA)-occurs when blood flow to part of brain is stopped briefly

—mini stroke6. Encephalitis- acute inflammation of brain7. Homonymous hemianopsia- loss vision in one side visual field8. ICP- increased intracranial pressure9. Nuchal rigidity- neck stiffness10.Posturing:

a) Decerebrate- legs and arms extended, toes plantar flexed, arms adducted and wrist pronated with fingers flexed

b) Decorticate-arms adducted & flexed, wrist & fingers flexed on chest, legs extended, internally rotated w/ plantar flexion of feet.

11.Paralysis-loss muscle fxn in part of bodya) Flaccid- decreased muscle toneb) Spastic- increased muscle tonec) Paraplegia- paralysis & loss sensation in legsd) Tetraplegia- paralysis arms & legse) Hemiplegia- paralysis one side bodyf) Upper motor neuron-originate in the cerebral cortex or brainstem and connect to

the skeletal muscle—innervate skeletal muscles of arms, legs, trunk etcg) Lower motor neuron- connect the brain and spinal cord to skeletal muscles,

bringing the impulse from the UMN to the muscles12.Trephine-surgical instrument for cutting out circular pieces of bone or corneal tissue STRUCTURE OF NERVOUS SYSTEM A. NERVOUS SYSTEM

1. CNS- brain & spinal cord2. PNS- 12 cranial & 33 spinal nerves

a) Autonomic nervous system- regulation involuntary body fxns i. Parasympathetic nervous system-maintenance of normal body fxns ii. Sympathetic nervous system-fight or flight

3. Cells4. Neuron- conducts & receives impulses5. Neuroglial cell- supports, nourishes and protects neuron

a) Oligodendrite- CNS, white matter- production myelin sheath (Swann cell in PNS)

b) Astrocyte- PNS, grey matter- supports cell, forms blood brain barrier. when injury acts as phagocyte

c) Ependemal cell- line ventricles brain- produce CSF 20-30mL/hrd) Micoglia-phagocyte

C. CRANIAL NERVESI. Olfactory- smellII. Optic- visionIII. Oculomotor- movement of eye

and superior levator palpabreIV. Trochlear- eve movement &

superior obliqueV. Trigeminal- sensation in face,

biting, chewing, swallow

VI. Abducens-eye movement & lateral rectus

VII. Facial-muscles of expressionVIII. Vestibulocochlear- hearingIX. Glossopharyngeal- tongue &

tasteX. Vagus- heart, lung, stomach,

intestines

XI. Accessory- sternocleidomastoid, trapezius & other neck muscles

XII. Hypoglossal- tongue and buccinator

NERVE GENERATION • To maintain resting membrane potential (action potential), need energy (ATP) to pump

Na+ out of cell (NA-K+ pump)àACTION POTENTIAL.• Neurons release chemicals into synapse:

Acetylcholine-activates muscle in PNS decrease seen in alzheimers, decreased receptors seen in myasthenia gravis

Epinephrine & norepinephrine- fight or flight, speeds up physiologic respones Serotonin-mood, emotions, sleep, increased w/ schizophrenia Dopamine- emotions, mood, motor control, decreased w/ Parkinson's Gamma-aminobutyric acid (GABA)- regulates muscle tone Endorphins well being, analgesia (feel goods) - & enkephalins-regulate nocioception

in body (noxious stimuli) Substance P- pain transmission-morphine blocks

I. Cerebruma) Frontal lobe- higher level fxn, intellectual fx, social appropriateness, creative

thinking, long term memory, personality Broca’s area- motor aspects speech- damage= can understand spoken

word, but can’t properly form words or produce speech--expressive(motor) aphasia- difficulty speaking & writing

b) Parietal- sensory & spatial, interpretation of touch, pressure & pain as well as distinguish objects, shapes & sizes—pin prick test palm of hand or place object in hand w/ eyes closed

c) Temporal-hearing, speech, behaviour & memory Wernicke's area- comprehension & recognition of written & spoken word,

damage=sensory(receptive) aphasiaà speech & meanings not understood d) Occipital lobe- visione) Hypothalamus- control autonomic nervous system, endocrine, motor control—

maintain homeostasisf) Thalamus-sensory perception & motor control, sleep-wake cyclesg) Limbic system-primitive –emotions & motivations for survival—anger, sex, eating

II. Brainstem- pons, midbrain, medullaà respirations, vasomotor & cardiac fxns etcIII. Cerebrum- coordination voluntary movement, posture, equilibrium & gait

A. LUMBAR PUNCTURE- CSF analysis, med. Administration, assess spinal blocks etc. Contraindicated ICP & skin infection . For pressure readings, CSF analysis, medication

BEFORE: Informed consent Explain & reinforce HCP

Note discomfort w/ injection, pain leg Void Assist into fetal position

-checks for spinal blocks, decreasing mild-moderate ICP AFTER:

Strict bed rest HOB flat 4-8hrs Neuro, neurovasc & VS Encourage fluids to decrease spinal headache Admin. Analgesics spinal headache

B. CEREBRAL ANGIOGRAPHY- illumination of cerebral arteries, injection dye into femoral artery, -dx aneurysm, arteriovenous malformations,

Before: Assess allergy to iodine, shellfish, contrast media Reinforce procedure & informed consent

Inform must remain still, head immobile, Burning & heat on injection NPO 8-12hrs Remove hairpins, jewellery, hearing aides etc Baseline VS, neuro, neurovasc Void Admin analgesics

-occlusions, leaky blood, displacements After:

Strict bed rest w/ affected leg extended until off bed rest Check for bleeding @ puncture site Check neurovasc, neuro, VS Maintain pressure dressing & ice Encourage fluids to help excrete dye

C. CT SCAN- 3D imaging w/without dye Before: if using dye

Check for allergies Explain procedure & informed consent Instruct remove hairpins, jewellery etc No food 4-6hrs prior (can have fluids)

After: Assess delayed allergic rx. IV fluids

-tumours, infarcts, hemorrhage, hydrocephalus, bone malformationsD. ELECTROENCEPHALOPGRAPHY (EEG

BEFORE: Explain procedure If for sleep deprived, instruct wake at 2-3a.m & stay awake for rest of night Avoid stimulants & depressants; anticonvulsants if D.O

Monitor for seizures Shampoo hair before & after procedure

records electrical activity of cerebral hemispheres on ambulatory basis

E. MRI BEFORE:

Informed consent Explain procedure

Hard, cold surface, noisy, earplugs available, if claustrophobic sedative given Remove all metal clothing, jewellery etc.

-enhanced when use Galladium (non-iodine), -Detects abnormalities of brain & spine, -contraindicated in those with metal implants, pacemakers, pregnant, confused, agitated, tattoos, unstable VS, continuous life support

F. ELECTROMYOGRAPHY BEFORE:

May cause discomfort Some may need sedative

AFTER: Comfort measure Inspect needle sites

- Dx neuromuscular, LMN, & peripheral nerve disorders- -EMG lab/bedsideà electrode placed along nerve- --test muscle potential, needle electrode inserted

G. TRANSCRANIAL DOPPLER Measures time needed for pulse travel specific depth & return to skulls surface