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Patho Final
CNS
Question | Answer |
---|---|
The Nervous system is composed of 2 cell types. What are they and what are their functions? | Nervous system is composed of 2 cell types: neurons (generate and transmit nerve impulses) and glial cells (provide supportive fx to neurons w/o transmitting impulses) |
What are the 3 basic components of neurons? | (1) cell body containing organelles, (2) dendrites that receive signals and conduct them to the cell body, (3) axon that generates and conducts action potentials. |
Each neuron secretes one principal ____ that is excitatory if it ____ the target neuron or inhibitory if it results in _____? | Each neuron secretes one principal neurotransmitter that is excitatory if it depolarizes the target neuron or inhibitory if it results in hyperpolarization. |
What are the 3 basic configurations neurons come in based on the location of the cell body and the relative length & # of dendrites and axons? | Neurons come in 3 basic configurations based on the location of the cell body and the relative length and # of dendrites and axons: multipolar, bipolar, and unipolar |
What is a multipolar neuron? | Multipolar – lg # of dendrites from one cell body and one axon, most common |
What is a bipolar neuron? | Bipolar – have only one dendrite and one axon extending from the cell body, prevalent in the retina, cochlea, and olfactory structures |
What is a unipolar neuron? | Unipolar – single process protruding from cell body, splits to form a dendrite and axon, prevalent in the somatosensory nerves |
___ are not capable of generating action potentials? | Glia – not capable of generating action potentials. |
What are the 4 types of Gila? | 4 types: oligodendrocytes, astrocytes, microglia, and ependymal cells. |
___ is a type of gila that form the myelin sheath that wraps around nerve axons to insulate and speed the rate of action potential conduction? | Oligodendrocytes |
___ is a type of gila that have foot processes that contact the brain capillaries and maintain the blood brain barrier? | Astrocytes have foot processes that contact the brain capillaries and maintain the blood-brain barrier |
Others types of ____ regulate ionic balance of interstitial fluid or transfer nutrients from capillarires to neurons and release molecules which bind to neuron receptors and modulate neurotransmission? | Astrocytes |
What is the function of microglia? | Microglia provide phagocytic function in CNS. |
What does ependymal cells line? What do they produce? What do they maintain? | Ependymal cells line ventricles and central canal of spinal cord, produce CSF and maintain CSF-brain barrier |
Why is myelination important? | Wraps around nerve axons to insulate and speed the rate of action potential conduction, and gives the white matter its color |
The Brain is composed of what structures? | Cerebrum; diencephalon, cerebellum, & brain stem |
What is the cerebrum composed of? | Cerebrum – Cerebral cortex (outermost layer, has 6 layers), limbic system (memory, emotion), basal ganglia (movement), corpus callosum (means of communication b/t R and L hemispheres) |
What is the diencephalon composed of? | Diencephalon – Thalamus, hypothalamus, epithalamus, ventral thalamus |
What does the thalamus do? | (relay sensory info, motor, emotions, language, creativity, complex thought) |
What does the hypothalamus do? | (endocrine activity, ANS, sex drive, temp, appetite, sleep, homeostasis) |
What does the epithalamus contain? | (pineal gland, circadian rhythms) |
What does the ventral thalamus contain? | (basal ganglia structure subthalamic nucleus) |
What is the function of the cerebellum? | Cerebellum (coordinate and smooth movements, maintain posture and balance) |
What is the brain stem composed of? | Midbrain, pons, medulla oblongata |
What is the function of the brain stem? | Brain stem (transmission b/t brain and spinal cord) |
What is the function of the midbrain? | Midbrain (holds motor tracks to spinal cord) |
What is the function of the pons? | pons (regulate respiration and CV fx) |
What is the function of the medulla? | medulla oblongata (regulate respiration and CV fx, swallowing, vomiting, coughing, sneezing) |
What is the function of the spinal cord? | Spinal cord – conveys nerve impulses b/t brain and 31 spinal nerve pairs that maintain posture, respond to pain, urination, and muscle tone. |
What does the white matter of the spinal cord consist of and what does it form? | The white matter consists of bundles of mylenated axons forming tracts that run up & down the cord, they are somatotopically organized |
_____ - innervation of a particular region is connected to specific region of cerebral cortex. Cord travels in small lumen protected by vertebral column? | somatotopically organized |
What does a cross section of the spinal cord revel? | Cross section reveals butterfly pattern of gray matter surrounded by white matter with 3 horns of neuron cell bodies, synapses and unmylenated interneurons. |
What are the 3 unmylenated interneurons that the cross section of the spinal cord revels? | ventral (motor neurons), dorsal (sensory neurons), and lateral (sympathetic neurons). |
The ____ matter of the spinal cord is divided into columns that containing nerve fibers to the brain, which allows afferent and efferent impulses from the brain to spinal cord? | white |
What is the acronym/saying that helps u remember the cranial nerves? | Cranial Nerves: On Old Olympus Towering Tops A French And German Viewed Some Hops |
Where is the olfactory sense located? | nasal mucous membrane |
What is the function of the olfactory? | olfaction (smell) |
Where is the optic nerve located? | Retina |
What is the function of the optic nerve? | Vision |
Where is the oculomotor nerve located? | Midbrain |
What is the function of the oculomotor nerve? | Eye & lid movement, pupil |
What is the function of the trochlear nerve? | lateral eye movement |
Where is the trochlear nerve located? | lower midbrain |
Where is the trigeminal nerve located? | Opthalamic-forehead, eyes; Maxillary-upper jaw, lip; & mandibular-lower jaw |
What is the function of the trigeminal nerve? | In General Sensation; Opthalamic-sensation of forehead/eye/scalp; Maxillary sensation of cheek/upper lip; & Mandibular sensation of chin/low jaw, chewing |
What is the function of the abducans? | taste (anterior tongue), face muscles |
Where is the abducans nerve located? | lower pons |
Where is the facial nerve located? | pons |
What is the function of the facial nerve? | hearing |
Where is the vestibulocochlear located? | Cochlea, inner ear |
What is the function of the vestibulocochlear nerve? | equilibrium |
What is the function of the glossopharyngeal nerve? | tatse (post tongue), sliva, swallowing |
Where is the glossopharyngeal nerve located? | medulla |
Where is the spinal accessory located? | medulla and cervical cord |
What is the function of the spinal accessory nerve? | voice, head & shoulder movement |
What is the function of the hypoglossal nerve? | tongue mvt (sppech), swallowing |
Where is the hypoglossal nerve located? | medulla |
The spinal nerves divide into 2 sections as they make contact with ___ & ____? | Spinal nerves divide into 2 sections as they make contact with cord - ventral & dorsal roots. |
Ventral roots contain motor neurons that originate in the ___ & travel in the spinal nerve to ____? | Ventral roots contain motor neurons that originate in the anterior horn & travel in the spinal nerve to skeletal muscles. |
Dorsal roots carry sensory information from where to where? | Dorsal roots carry sensory information from somatic receptors to neurons in the posterior horn. |
What are the 31 nerve pairs in the spinal cord? | 31 nerve pairs:8 Cervical; 12 Thoracic; 5 Lumbar; 5 Sacral; 1 Coccygeal |
The Nervous system is composed of 2 cell types. What are they and what are their functions? | Nervous system is composed of 2 cell types: neurons (generate and transmit nerve impulses) and glial cells (provide supportive fx to neurons w/o transmitting impulses) |
What are the 3 basic components of neurons? | (1) cell body containing organelles, (2) dendrites that receive signals and conduct them to the cell body, (3) axon that generates and conducts action potentials. |
Each neuron secretes one principal ____ that is excitatory if it ____ the target neuron or inhibitory if it results in _____? | Each neuron secretes one principal neurotransmitter that is excitatory if it depolarizes the target neuron or inhibitory if it results in hyperpolarization. |
What are the 3 basic configurations neurons come in based on the location of the cell body and the relative length & # of dendrites and axons? | Neurons come in 3 basic configurations based on the location of the cell body and the relative length and # of dendrites and axons: multipolar, bipolar, and unipolar |
What is a multipolar neuron? | Multipolar – lg # of dendrites from one cell body and one axon, most common |
What is a bipolar neuron? | Bipolar – have only one dendrite and one axon extending from the cell body, prevalent in the retina, cochlea, and olfactory structures |
What is a unipolar neuron? | Unipolar – single process protruding from cell body, splits to form a dendrite and axon, prevalent in the somatosensory nerves |
___ are not capable of generating action potentials? | Glia – not capable of generating action potentials. |
What are the 4 types of Gila? | 4 types: oligodendrocytes, astrocytes, microglia, and ependymal cells. |
___ is a type of gila that form the myelin sheath that wraps around nerve axons to insulate and speed the rate of action potential conduction? | Oligodendrocytes |
___ is a type of gila that have foot processes that contact the brain capillaries and maintain the blood brain barrier? | Astrocytes have foot processes that contact the brain capillaries and maintain the blood-brain barrier |
Others types of ____ regulate ionic balance of interstitial fluid or transfer nutrients from capillarires to neurons and release molecules which bind to neuron receptors and modulate neurotransmission? | Astrocytes |
What is the function of microglia? | Microglia provide phagocytic function in CNS. |
What does ependymal cells line? What do they produce? What do they maintain? | Ependymal cells line ventricles and central canal of spinal cord, produce CSF and maintain CSF-brain barrier |
Why is myelination important? | Wraps around nerve axons to insulate and speed the rate of action potential conduction, and gives the white matter its color |
The Brain is composed of what structures? | Cerebrum; diencephalon, cerebellum, & brain stem |
What is the cerebrum composed of? | Cerebrum – Cerebral cortex (outermost layer, has 6 layers), limbic system (memory, emotion), basal ganglia (movement), corpus callosum (means of communication b/t R and L hemispheres) |
What is the diencephalon composed of? | Diencephalon – Thalamus, hypothalamus, epithalamus, ventral thalamus |
What does the thalamus do? | (relay sensory info, motor, emotions, language, creativity, complex thought) |
What does the hypothalamus do? | (endocrine activity, ANS, sex drive, temp, appetite, sleep, homeostasis) |
What does the epithalamus contain? | (pineal gland, circadian rhythms) |
What does the ventral thalamus contain? | (basal ganglia structure subthalamic nucleus) |
What is the function of the cerebellum? | Cerebellum (coordinate and smooth movements, maintain posture and balance) |
What is the brain stem composed of? | Midbrain, pons, medulla oblongata |
What is the function of the brain stem? | Brain stem (transmission b/t brain and spinal cord) |
What is the function of the midbrain? | Midbrain (holds motor tracks to spinal cord) |
What is the function of the pons? | pons (regulate respiration and CV fx) |
What is the function of the medulla? | medulla oblongata (regulate respiration and CV fx, swallowing, vomiting, coughing, sneezing) |
What is the function of the spinal cord? | Spinal cord – conveys nerve impulses b/t brain and 31 spinal nerve pairs that maintain posture, respond to pain, urination, and muscle tone. |
What does the white matter of the spinal cord consist of and what does it form? | The white matter consists of bundles of mylenated axons forming tracts that run up & down the cord, they are somatotopically organized |
_____ - innervation of a particular region is connected to specific region of cerebral cortex. Cord travels in small lumen protected by vertebral column? | somatotopically organized |
What does a cross section of the spinal cord revel? | Cross section reveals butterfly pattern of gray matter surrounded by white matter with 3 horns of neuron cell bodies, synapses and unmylenated interneurons. |
What are the 3 unmylenated interneurons that the cross section of the spinal cord revels? | ventral (motor neurons), dorsal (sensory neurons), and lateral (sympathetic neurons). |
The ____ matter of the spinal cord is divided into columns that containing nerve fibers to the brain, which allows afferent and efferent impulses from the brain to spinal cord? | white |
What is the acronym/saying that helps u remember the cranial nerves? | Cranial Nerves: On Old Olympus Towering Tops A French And German Viewed Some Hops |
Where is the olfactory sense located? | nasal mucous membrane |
What is the function of the olfactory? | olfaction (smell) |
Where is the optic nerve located? | Retina |
What is the function of the optic nerve? | Vision |
Where is the oculomotor nerve located? | Midbrain |
What is the function of the oculomotor nerve? | Eye & lid movement, pupil |
What is the function of the trochlear nerve? | lateral eye movement |
Where is the trochlear nerve located? | lower midbrain |
Where is the trigeminal nerve located? | Opthalamic-forehead, eyes; Maxillary-upper jaw, lip; & mandibular-lower jaw |
What is the function of the trigeminal nerve? | In General Sensation; Opthalamic-sensation of forehead/eye/scalp; Maxillary sensation of cheek/upper lip; & Mandibular sensation of chin/low jaw, chewing |
What is the function of the abducans? | taste (anterior tongue), face muscles |
Where is the abducans nerve located? | lower pons |
Where is the facial nerve located? | pons |
What is the function of the facial nerve? | hearing |
Where is the vestibulocochlear located? | Cochlea, inner ear |
What is the function of the vestibulocochlear nerve? | equilibrium |
What is the function of the glossopharyngeal nerve? | tatse (post tongue), sliva, swallowing |
Where is the glossopharyngeal nerve located? | medulla |
Where is the spinal accessory located? | medulla and cervical cord |
What is the function of the spinal accessory nerve? | voice, head & shoulder movement |
What is the function of the hypoglossal nerve? | tongue mvt (sppech), swallowing |
Where is the hypoglossal nerve located? | medulla |
The spinal nerves divide into 2 sections as they make contact with ___ & ____? | Spinal nerves divide into 2 sections as they make contact with cord - ventral & dorsal roots. |
Ventral roots contain motor neurons that originate in the ___ & travel in the spinal nerve to ____? | Ventral roots contain motor neurons that originate in the anterior horn & travel in the spinal nerve to skeletal muscles. |
Dorsal roots carry sensory information from where to where? | Dorsal roots carry sensory information from somatic receptors to neurons in the posterior horn. |
What are the 31 nerve pairs in the spinal cord? | 31 nerve pairs:8 Cervical; 12 Thoracic; 5 Lumbar; 5 Sacral; 1 Coccygeal |
Where are the C1-4 nerves distribution & what is the plexus? | plexus-cervical; Distribution-diaphragm, neck, & hyoid bone |
Where are the C5-8, T1 distributed and the Plexus? | plexus-brachial; distribution upper arm, forearm, wrist, digits, thumb, upper arm |
Where are the L1-4 distributed and the Plexus? | Plexus- lumbar distribution-hip, knee, inner thigh |
Where are the L4-5, S1-3 distributed and the Plexus? | Plexus – sacral distribution- gluteus med, min, max; thigh, leg, foot; perineum |
Where is the S4-5, Coccygeal distributed and the plexus? | plexus-coccygeal; distribution skin on coccyx |
What are the 2 pairs of arteries that supply blood to the brain? | Blood Supply to Brain supplied by 2 pairs of arteries: internal carotid arteries and vertebral arteries |
What are the 3 branches of the internal carotid? | Internal Carotid – anterior circulation. 3 branches: anterior and middle cerebral arteries and posterior communicating arteries |
Where does the vertebral posterior circulation enter? | Vertebral – posterior circulation. Enter skull at foramen magnum join at pons to form basilar arteries |
What is the circle of willis? | Circle of Willis: ring of vessels that unite the anterior and posterior circulation at the base of the brain. |
____ – result from sudden occlusion of a cerebral artery secondary to thrombus formation or embolization? | Ischemic stroke |
Sudden blockage of a cerebral artery by thrombus or embolus produce acute ischemia in the territory served by the artery resulting in insufficient blood flow leading to _____ and ____...? | leading to oxygen deprivation and rapid cerebral deterioration and neurologic deficits. |
If the clot can be lysed b/4 permanent tissue damage occurs, it’s called a ____? | TIA |
What is a thromotic stoke associated with? | Thrombotic stroke – assoc w/ atherosclerosis and hypercoagulable states, so clots form from platelet aggregation or atherosclerotic plaques |
What are embolic strokes usullay from? | Embolic stroke – emboli are usually from a cardiac source, although disruptions in carotid artery plaques may lead to downstream embolization, |
What are the embolic strokes cardiac sources from? | cardiac sources can be from chronic a-fib or thrombi formation in static areas which can dislodge and travel to the cerebral circulation |
What are the s/s of TIA? | s/s – contralateral hemiplegia, hemisensory loss, contralateral visual field blindness common |
____ stroke are intracerebral hemorrhage usually occurs b/c of severe and long-lasting ____, ___ mortality? | Hemorrhagic stroke – intracerebral hemorrhage usually occurs b/c of severe and long-lasting HTN, 38% mortality |
Where do most hemorrhagic strokes occur? | most occur in basal ganglia or thalamus. |
What can a large hemorrhage stroke lead to? | If hemorrhage is lg, may lead to ↑ ICP, herniation, and death |
What is a focal head injury? | Focal – (coup) localized to site of injury, damage can be superficial or deep |
What is a polar head injury? | Polar -(coup/contracoup) consequence of brain shift within skull and meninges during acceleration-deceleration movement with two poles of brain being damaged |
What is a diffuse head injury? | Diffuse – movement of brain within cranial vault causes widespread neuronal damage, stretching and shearing forces |
What is a concussion head injury? | Concussion – when head injury produces an altered LOC but no evidence o f brain damage found, common with sports, graded according to severity |
What is a contusion head injury? | Contusion – MRI or CT reveals area of brain damage |
Who are spinal cord injuries a problem for? | Spinal cord injuries – problem of young (20-24yrs, males, WE, summer) |
What are the causes of spinal cords? | causes MVA, violence, falls, recreational activities as a result, compression, blunt trauma, hyperflexion, or hyperextension cause penetration/transection of spinal cord |
What are the s/s of spinal cord injury? | s/s – immediate loss of fx below level of injury, spinal shock, flaccid paralysis, loss of spinal reflexes, loss of pain and proprioception and sensations, bowel/bladder dysfunction. |
What happens with upper thoracic injury? | With upper thoracic injury HoTN d/t peripheral vasodilation, bradycardia. |
What happens in a T6 or above injury? | With T6 or above autonomic dysreflexia characterized by sudden HoTN, HA, upper body flushing, bradycardia, lower body vasoconstriction, goosebumps, sweating usually caused by a full bladder or constipation |
_______ – disease of mobility, idiopathic (slow onset) or acquired (rapid onset) from infection, intoxication, and trauma, typically drug toxicity? | Parkinson |
What does Parkinson result from? | Disease results from degeneration of the pigmented dopaminergic neurons found in the substantia nigra, Lewy bodies may be found along with amyloid plaques in pts with dementia |
Lwey bodies may be found along with amyloid plaques in pts with dementia. What is the cause of this thought to be? | cause unknown, thought to be genetic (α-synuclein of Lewy bodies, parkin for protein degradation and clearance), or environmental (caffeine inverse relationship, pesticide rotenone increased risk) |
What are the s/s of Parkinson? | s/s – loss of flexibility, ache, fatigue, worse one side first then both, tremor, bradykinesia/hypokinesia, loss of facial expression, infrequent eye blinking, small handwriting, speech low and monotonous and dysarthric or mumbling |
delayed swallowing/drooling, short shuffling gait, balance problems, orthostatic HoTN, depression, daytime sleepiness, dementia are also s/s of ____? | parkinson |
What is the most common cause of Alzheimer? | Alzheimer – most common cause of dementia, |
What are the 2 neurologic lesions of an autopsy of Alzheimer’s show? | neurofibrillary tangles (tau proteins that stabilize microtubules gets chemically twisted into helical filaments) and amyloid deposits (senile plaques and cerebrovascular accumulations), brain atrophy. |
What 3 mechanisms does the damage of alzheimer’s involve? | Damage involves changes in 3 mechanisms: nerve cell communication, metabolism and repair |
What are the risk factors for alzheimer’s? | Risk factors – age, family HX (1st degree), or presence of apolipoprotein E4 on Ch19 |
What are the s/s of alzheimer’s? | progressive memory loss (short term especially), decreased ability fx work & social, agitation common, poor judgmnt, problem solving, & communication, difficulty w/ ADL’s, loss of bladder/bowel eventual, difficulty eating, swallowing, wt loss |
What is bell palsy? | an acute idiopathic paresis or paralysis of the facial nerve involving an inflammatory reaction at or near stylomastoid foramen or in bony facial canal, may be viral infection (antibodies from HSV simplex and zoster found in pts) |
What are the s/s of bell palsy? | rapid, unilateral facial weakness with facial droop and diminished eye blink, hyperacusis, decreased lacrimation, pt may feel heavy sensation in face but maintain feeling, decreased taste, posterior auricular pain |
What is crutzfeldt Jacob disease? | Crutzfeldt Jacob disease – a prion disease, proteinaceous infection of prions, rare, rapidly progressive dementia, |
What does crutzfeldt Jacob disease start with? | starts with memory changes and ataxia |
At what age does crutzfeldt Jacob disease peak and it is fatal w/in ___? | peaks in 70yr olds, fatal w/i 7 months. |
In crutzfeldt Jacob disease what are prions a problem in? | Prions are problems in Kura, mad cow disease, Scrapie in sheep, transmitted through infected food source. |
Why must people doing the autopsy of a pt with crutzfeldt Jacobs disease use extreme caution? (hint Prions) | Autopsy must use extreme caution as can’t kill prions, no nucleus, corruption of normal cell components |
What is the hydrocephalus? | Hydrocephalus – abnormal accumulation of CSF in the cerebral ventricular system |
What is hydrocephalus generally associated with? | generally assoc w/ congenital defect (neural tube defect), |
Hydrocephalus occurs occasionally in adults/elderly as a consequence of mass lesions or after hemorrhage 3 types. What are the 3 types? | normal-pressure; obstructive, & communicating |
Hydrocephalus normal pressure ___ volume increases w/o change in ___ pressure b/c brain tissue has been lost (___), arterial HTN may be risk? | Normal-pressure – CSF volume increases w/o change in CSF pressure b/c brain tissue has been lost (Alzheimers), arterial HTN may be risk |
Hydrocephalus obstructive is an obstruction at some point in ___ or ___ pathways? | obstructive – an obstruction at some point in intraventricular or extraventricular pathways |
Hydrocephalus communicating is an acquired abnormality I capacity to absorb ___ from subarachnoid space, no ____ to flow of fluid b/t ___, ___ or ___? | Communicating – (acquired) an abnormality I capacity to absorb fluid from subarachnoid space, no obstruction to flow of fluid b/t ventricles, infection or trauma may be cause |
___ is localized collections of blood within the cranium? | Intracranial hematoma – localized collection of blood within cranium. |
What are the three common types after HI of intercranial hematomas? | 3types common after HI: Epidural; subdural; and subarachnoid |
____– blood in epidural space (b/t inner surface of skull & dura mater), vessels susceptible to injury w/ skull fractures, common disruption of middle meningeal artery (acute blood loss), brief period of disturbed consciousness followed by lucid period? | epidural |
___ – blood in subdural space (b/t dura and outer arachnoid membrane), vessels can be sheared or torn with rapid changes in head velocity (slow blood loss), delayed symptoms: HA, vomiting, blurred vision? | Subdural |
____ – blood subarachnoid space (b/t outer arachnoid membrane and pia mater) usually filled with CSF, symptoms: HA, meningeal irritation, bloody spinal tap, common cause is aneurysm? | Subarachnoid |
What is ICP? | ICP is the pressure exerted by contents of the cranium |
What is the normal level of ICP? | NL 0-15mmHg. |
Elevated ICP may occur in most types of ___, assoc w/ impaired ___ fx d/t compression of brain structures? | Elevated ICP may occur in most types of brain injuries, assoc w/ impaired neuro fx d/t compression of brain structures. |
T/F In ICP there is a finite ability to accommodate changes (compliance) in volume b/4 elevations in ICP occur. | true |
What are some things that can cause elevated ICP? | Sneezing, coughing, straining, and head-dependent positions cause elevated ICP. |
What are the most common cause for increased ICP? | The most common cause for ↑ ICP: stroke, trauma, and tumors. |
What is the common etiology for ICP? | Common etiology: ↑ brain tissue volume, ↑ CSF volume, ↑ blood volume. |
What are the s/s of ICP? | HA, vomiting, altered LOC (drowsiness-unconscious: inability to move, verbalize, or open eyes), blurry vision, papilledema, pupillary response, motor paresis, altered respiratory patterns. |
What is a cushing reflex? (Hint happens in increased ICP) | Cushing reflex – sBP may exceed 22mmHg accompanied by bradycardia, & widening pulse pressure |