nervous system Flashcards
(84 cards)
1
Q
define paresthesia
A
non-painful abnormal sensations such as
numbness,
tingling,
prickling,
“pins & needles”
2
Q
define hyperesthesia
A
unpleasant hypersensitivity;
may be due to increased response or decreased threshold;
-includes both allodynia & hyperalgesia
3
Q
define allodynia
A
painful response to a stimulus that is NOT normally painful.
Ex: clothes or sheets touching skin
- showering
- wind on the face
4
Q
define hyperalgesia
A
- increased response to stimuli that is typically painful
(ex: increased response to a pinprick)
5
Q
migraine HA:
list signs/symptoms
A
- unilateral moderate to severe HA
- retro/supraorbital
- throbbing/pusatile
- associated with photo- and/or phonophobia
- associated w/N&V (esp children)
- 80% without aura; 20% experience aura
- aura usu visual (scintillating scotoma; blind spots)
6
Q
migraine HA:
describe population(s) most affected
A
pre-puberty: males=females or males > females
post-puberty: females > males
occurences usually decrease w/pregnancy and post-menopause
7
Q
migraine HA:
describe abortive and preventative treatments
A
Medication
Acute (abortive):
- Ergotamines
- dihydroergotamine (DHE 45)
- Tryptans (5-HT1/serotonin receptor agonists)
- sumatriptan (Imatrex)
- rizatriptan (Maxalt)
- NSAIDs
- ibuprofen, etc
Prophylaxis (≥2-4 HA’s/ month):
-anti-epileptic drugs (AEDs)
- valproate
- divalproex
- topiramate
- Beta-blockers:
- propanolol, etc
8
Q
cluster HA:
-s/s
A
- unilateral stabbing/squeezing pain
- VERY severe brief pain
- not associated w/N&V or aura
- facial flushing, ipsilateral eye tearing, conjunctival injection, nasal congestion/rhinorrhea , Horner sysdrome
- think “labor ctx for the eyes” as the pain comes and goes like ctxs
- pain lasts for minutes and recurs several times per day
9
Q
cluster HA-
risk factors
A
-risk factors: smoking, ETOH use, male sex
10
Q
cluster HA:
treatments (acute & preventative)
A
-acute tx:
- high flow O2
- triptans
- ergotamines
preventative:
- lithium
- calcium channel blockers
11
Q
tension-type HA:
s/s, cause, triggers, treatments
A
dull, achy, vice-like mild/mod pain
diffuse or headband location
underlying cause probably sustained ctx of occipital muscles
triggers: hunger, low bld glucose, lack of sleep, anger/stress
treatments: OTC pain relievers, non-pharm therapies: massage, accupuncture, biofeedback, etc
12
Q
Name the locations and effects of Beta-adrenergic receptors
A
ß-1: heart:
- increased HR (+chronotropic effect)
- increased conduction velocity (+ dromotropic effect
- increased contaction force or strength (+ionotropic effect)
ß-2: smooth muscle of lungs, GI, GU
- bronchiole dilation, dec’d GI motility; dc’d labor; dec’d urine flow
ß-3: adipocytes:
- increased FA catabolism; activates uncoupling protein (increased heat production)
13
Q
Define somatosensory
A
senses that can be felt almost everywhere through out the body, such as temperature, touch, pain, pressure, itchiness, vibration (versus senses are localized to a specialized sense organ such as taste, smell, hearing, sight)
14
Q
Describe the characteristics of the 4 types of nerve fibers that transmit somatosensory information
A
TYPE DIAMETER MYELINATED? SENSES TRANSMITTED
A-alpha largest/fastest yes -mechanosensation, -proprioception
A-beta large/fast yes -pressure, touch, vibration
A-delta medium/fast lighty -localized, sharp pain
C smallest/slowest no -dull, achy, diffuse pain
15
Q
What is another name for pseudotumor cerebri?
A
idiopathic intracranial hypertension
16
Q
Differentiate between vertigo caused by
Benign Paroxysmal Positional Vertigo
and vertigo caused by CNS lesions
A
BPPV:
- latency: vertigo/nystagmus begins few seconds-60 sec after head position change
- habituation: symptoms/nystagmus stops upon repetition of maneuver
- fatigability: symptoms subside after 10-60 seconds
- nystagmus is usually horizontal
Vertigo from CNS lesion:
- no latency, no fatigability, no habituation
- nystagmus is often vertical
17
Q
Name the maneuvers to diagnosis and correct BPPV
A
- diagnostic maneuver: Dix-Hallpike maneuver (aka Nylen-Barany test) (with pt’s head turned 45 degrees to one side, pt quickly leans back with head hanging off table by 30 degrees; nystagmus appears within a few seconds to one minute= positive test)
- Corrective maneuver: Epley (aka vestibular exercises): from the position above: pt turns head to opposite side 45 degrees, hold for 30 seconds, then pt turns on side and tilts head towards floor, then with head still turned, sit up on side of bed for ~30 seconds, with head down (chin to chest) for 30 sec. Can be repeated until symptoms stop.
18
Q
What 3 structures make up the diencephalon?
A
- thalamus
- hypothalamus
- epithalamus (includes pineal gland, habenula)
19
Q
Where do the dural venous sinuses empty?
A
- internal jugular veins
20
Q
reversed prompt
non-painful abnormal sensations such as
numbness,
tingling,
prickling,
“pins & needles”
A
define paresthesia
21
Q
reversed prompt
unpleasant hypersensitivity;
may be due to increased response or decreased threshold;
-includes both allodynia & hyperalgesia
A
define hyperesthesia
22
Q
reversed prompt
painful response to a stimulus that is NOT normally painful.
Ex: clothes or sheets touching skin
- showering
- wind on the face
A
define allodynia
23
Q
reversed prompt
- increased response to stimuli that is typically painful
(ex: increased response to a pinprick)
A
define hyperalgesia
24
Q
reversed prompt
senses that can be felt almost everywhere through out the body, such as temperature, touch, pain, pressure, itchiness, vibration (versus senses are localized to a specialized sense organ such as taste, smell, hearing, sight)
A
Define somatosensory
25
# reversed prompt
idiopathic intracranial hypertension
What is another name for pseudotumor cerebri?
26
# reversed prompt
* thalamus
* hypothalamus
* epithalamus (includes pineal gland, habenula)
What 3 structures make up the diencephalon?
27
Name the 2 types of embryonic nervous tissue precursor cells (and what they become)
(and which embryonic tissue they derived from)
* derived from ectoderm
* _neural stem cells_ --\> become neurons and glia of the **CNS** (except for microglia which come from mesoderm --\>monocytes in bone marrow)
* _neural crest cells_ --\> become neurons and glis of **PNS**
28
List the 3 embryonic developmental structures of the brain and what they become
* _prosencephalon_ (forebrain):
* telencephalon- becomes the cerebrum
* diencephalon- becomes epithalamus, thalamus, and hypothalamus
* _mesencephalon_ (midbrain): becomes midbrain
* _rhombencephalon_ (hindbrain): becomes the pons, medulla oblongata, and cerebullum
29
List the 3 divisions of the brain stem
* midbrain
* pons
* medulla oblongata
30
What 3 structures make up the diencephalon?
* epithalamus (pineal gland and habenula)
* thalamus
* hypothalamus
31
Where do the dural sinuses empty?
-into the internal jugular veins
32
What are the 2 major categories of the long tracts (neural)?
1. _Upper motor neurons_: efferent; traveling from cortex, passing thru the brain stem (crossing to opposite sides), down to synapse with lower motor neurons
2. _Somatosensory_- afferent, passing thru the brain stem (decussating) and synapsing in cerebral cortex
33
Regarding upper motor neurons:
trace the pathway of the corticospinal tract
starts in gray matter of cerebral cortex, axons pass thru brain stem, then most cross over to other side of spinal cord to synapse with lower motor neurons
34
Regarding upper motor neurons:
trace the pathway of the corticobulbar tract
-starts out in cerebral cortex, then either synapses with LMN on *same side* or *opposite* side of brain stem
35
List 4 signs of pathology in upper motor neurons
1. _hyperreflexia_- increase in muscle stretch reflex
2. _clonus_- rhythmic contraction of antagonist muscle groups
3. _hypertonia_- increased tone of skeletal muscle
4. _extensor planter response_- + Babinski sign (dorsiflexion of big toe when sole of foot is stroked with hard object- this is abnormal response in adults but normal in newborn-gone by 2 yrs old)
36
List 4 signs of pathology in lower motor neurons
1. hypotonia
2. hyporeflexia
3. atrophy
4. fasciculations (twitching)
37
"All excitatory and inhibitory signals that control skeletal movement converge on the __ \_\_\_ \_\_\_, also known as ___ \_\_\_ \_\_\_, or the ___ \_\_\_ \_\_\_\_."
1. alpha motor neuron
2. lower motor neuron
3. final common pathway
38
List the 2 pathways via which the somatosensory tracts travel and which senses travel together
(2 sets of four each)
* Dorsal Column Medial Lemniscal (DCML) pathway
* conscious proprioception
* vibration
* fine touch
* light pressure
* Antereolateral pathway:
* pain
* temperature
* gross/crude touch
* deep pressure
39
Describe the spinal nerve organization
| (starting from the cord)
* DORSAL:
* dorsal rootlets --\>
* dorsal root --\>
* dorsal root ganglia --\>
* spinal nerve trunk
* VENTRAL/ANTERIOR
* anterior rootlets --\>
* anterior root --\>
* spinal nerve trunk
SPINAL NERVE (mixed) - divides into anterior ramus and posterior ramus
40
Where does the spinal cord end in adults and newborns?
* adults: superior border of L2
* newborns: L3-4
41
What are the major functions of the basal nuclei?
* starting/initiating movement
* stopping/terminating movement
* cognitive processes: memory, attention, planning
* acts with limbic system to regulate emotions
42
Name 2 physiologic (versus anatomic)
components of the basal nuclei
* substantial nigra
* subthalamic nuclei
43
Name the 3 components of the basal nuclei
and their 2 subcategories)
* Lentiform nucleus:
* globus pallidus
* putamen
* Corpus Striatum
* putamen
* caudate nucleus (with a head, body, and tail)
44
What 5 diseases are related to disfunction of the basal nuclei?
* Parkinson's disease
* Huntington's chorea
* Tourette syndrome
* obsessive-compulsive disorder
* schizophrenia
45
What is a normal intracranial pressure for adults, children, and newborns?
What is a life-threatening ICP?
**Normal Adult Standing ICP:** -10 mmHg (negative ICP)
**Normal Supine Adult ICP:** 7-15 mmHg
* abnormal: \>15 mmHg
* pathologic: \>20 mmHg
* life-threatening: \> or = to 40 mmHg
**Normal for young children:** 3-7 mmHg
**Normal for term newborn**: 1.5-6 mmHg (can also be negative)
46
What is the effect of posture on intracranial pressure?
Standing or elevating the head results in decreased ICP.
Supine- higher ICP
47
What is the formula for calculating CPP (cerebral perfusion pressure)?
CPP= MAP - ICP
(MAP: Mean Arterial Pressure= 1/3 SBP +2/3 DBP)
Ex: SBP= 120 mmHg, DBP = 80 mmHg, and ICP = 10 mmHg
CPP= 93-10= 83 mmHg
48
What is another name for pseudotumor cerebri?
idiopathic intracranial hypertension (IIH)
49
# reversed prompt
What is anothe name for idiopathic intracranial hypertension (IIH)
pseudotumor cerebri
50
# reversed prompt
What do these 5 conditions have in common?
* Parkinson's disease
* Huntington's chorea
* Tourette syndrome
* obsessive-compulsive disorder
* schizophrenia
All are related to disfunction of the basal nuclei
51
What is the basic pathology of Parkinson's disease?
* neurons of substantial nigra (which produce dopamine) are destroyed by build up of protein clumps (Lewy bodies)
* lack of dopamine produced by the substantial nigra in basal nuclei leads to over supply of ACh --\> tremors, rigidity, bradykinesia, freezing
52
List the 4 movement signs of Parkinson's disease
* bradykinesia- slow movement, shuffling gait, weakness, fatigue (dx with reduced blinking of 8-12 times/minute
* resting tremors ("pill-rolling")
* postural instability- loss of balance
* rigidity- cogwheel rigidity
53
list 4 structural categories of neurotransmitters and
give examples of each
1. **_amino acids:_** glutamate, glycine, GABA, aspartate
2. **_monoamines:_** seratonin, histamine
* catecholamines: dopamine, epinephrine, norepinephrine
3. **_peptides:_** endorphins, enkephalins, dynorphins, substance P
4. **_other:_** nitric oxide (NO) (precusor is L-arginine), acetylcholine, carbon monoxide
54
Which amino acid is the precusor to catecholamines?
tyrosine
55
List the steps of the production of epinephrine
amino acid tyrosine --\> dopa --\> dopamine --\> norepinephrine --\> epinephrine
(in the adrenal medulla, 80% of norepi is converted to epinephrine)
56
Which amino acid is the precusor to the monoamine seratonin?
tryptophan
57
Name 3 families of endogenous opioid peptides
* endorphins
* enkephalins
* dynorphins
58
Name the 2 types of cholinergic receptors
* muscarinic:
* M1- gastric glands (increase secretion)
* M2- in heart (decrease rate and force of ctx)
* M3- pupils, salivary glands, bronchioles, GI smooth m, bladder
* M4- brain
* M5- brain
* nicotinic:
* muscle type (NM or N1)
* neuronal type (NN or N2)
59
Describe the categories of adrenergic receptors
* **Alpha**- located on arterioles
* alpha1- causes vasoconstriction of:
* skin, GI tract, kidney, brain
* alpha2- presynaptic CNS- inhibits release of norepi
* **Beta**
* beta1: heart (increased rate/ctx force
* beta2: lungs (bronchiole dilation)
* beta3: adipocytes (increase lipolysis)
60
Which body structures are NOT innervated by parasympathetic NS neurons (only sympathetic)?
- blood vessels
- sweat glands
61
Name the 2 receptors for vibration.
Which is for low frequency and which is for high frequency?
* lamellated corpuscles (Pacinian corpuscles)- high frequency
* corpuscles of touch (Meissner corpuscles) - low frequency
62
define dysesthesia
an abnormal sense of touch- burning/tingling sensation even from light touch of clothes/bedding
63
64
# reversed prompt
an abnormal sense of touch- burning/tingling sensation even from light touch of clothes/bedding
dysesthesia
65
Name the glial cells of the peripheral nervous system and give their functions
* **_schwann cells (aka neurolemmocytes)_**- wrap around axons, forming the myelin sheath; also clear debris and aid regrowth of PNS nerves
* **_satellite cells_**- similar function to astrocytes of CNS (protection, homeostasis)
66
Name the 4 types of glial cells of the CNS
* astrocytes
* microglia
* oligodendrocytes
* ependymal cells
67
Name 6 functions of astrocytes
* form glial scar when CNS injury occurs
* provide structural support, scaffolding
* homeostasis- can use it's glycogen to form lactate to provide E to neurons; regulates ion/nutrient concentrations
* forms the blood-brain (and blood-spinal cord) barrier
* take up/recycle neurotransmitters (clears synapses)
* influence neurons and other glial cells via exchange of substances
68
Name the location and functions of ependymal cells
* they create the lining of the cerebral ventricles and central canal of spinal cord
* secrete CSF in chroid plexus
* cilia aid in CSF circulation
* forms the blood-CSF barrier
* derived from neural stem cells
69
Describe microglia-
embryonic origin, general function, where found
- come from embryonic mesoderm --\> monocytes from red bone marrow
- found in CNS
- primary functions: inflammation (phagocytosis, antigen presentation, secretion of ROS to kill pathogens)
70
Describe the 4 variaties of synapses
* axoaxonal- axon to another axon
* axodendritic- axon to dendrite
* axosomatic- axon to neuron cell body (soma)
* dendrodentritic- dendrite to dendrite
71
define nuclei and tracts
* **_nuclei_**- bundle of neuronal somas (gray matter) located within the CNS
* **_tract_**- bundle of axons (white matter) in the CNS
72
define ganglion and nerves
* **ganglion**: bundle of neuronal cell bodies (somas) (gray matter) in the Peripheral nervous system
* **nerves**- collection of axons (white matter) in the PNS
73
describe white matter versus gray matter
* **white matter**- myelinated axons; found in the central portions of the brain and the peripheral portions of the spinal cord
* **gray matter**- neuronal cell bodies and unmyelinated axons; found in the outer region of the brain and inner region of the spinal cord; appears gray due to Nissel bodies in soma
74
describe afferent vs. efferent nerve fibers
* **afferent**: (**a**rrive to CNS); senosory fibers, travel from periphery into CNS; dorsal part of spinal cord
* **efferent**: (**e**gress); motor, travel from CNS to **e**ffector organs (skeletal muscle, smooth muscle, glands, cardiac muscle); ventral part of spinal cord
75
Describe the 2 types of neurotranmitter receptors and their effects
* ionotropic:
* ligand-gated ion channels (the NT is the ligand)
* excitatory if they allow entrance to Na+ or Ca++
* inhibitory if they allow Cl- to enter or K+ to leave cell
* cause graded potentials
* local, brief action
* metabotropic:
* NT binding causes 2nd messenger activation
* larger/slower/more wide-spread effects than ionotropic receptors
76
define IPSP
inhibitory post-synaptic potential
(example- if NT binding opens ion channels that cause Cl- to enter or K+ to leave, it causes hyperpolarization, making it less likely that an action potential will propagate)
77
define EPSP
**_e_**xcitatory **_p_**ost-**_s_**ynaptic **_p_**otential
(example- if NT binding opens ion channels that cause Na+ or Ca++ to enter, it causes hypopolarization, making it more likely that an action potential will propagate)
78
what is the difference between a neuromodulator and a neurotransmitter?
neuromodulators do NOT bind to ionotropic receptors; instead, they bind to metabotropic receptors, causing longer lasting effects
79
# fill in the blanks:
_neurotransmitter excitatory_/_inhibitory primary location_
glutamate
norepinephrine
GABA
dopamine
aspartate
glycine
acetylcholine
nitric oxide
histamine
serotonin
# fill in the blanks:
_neurotransmitter excitatory_/_inhibitory primary location_
glutamate usually excitatory brain, spinal cord
norepinephrine either-depending on receptors CNS, ANS
GABA usually inhibitory brain, spinal cord
dopamine either-depending on receptors areas of brain
aspartate excitatory
glycine inhibitory spinal cord
acetylcholine excitatory-skeletal m; either on organs brain, ANS, neuromuscular junction
serotonin usu inhibitory areas of brain, cord
80
describe the structural variety of neurons (ie, # of poles)
* unipolar: cell body and one process; not seen in adults; developmental stage
* pseudounipolar- one process that splits into 2; ex: dorsal root ganglion
* bipolar: cell body and one axon, one dendrite; ex: retinal neuron, inner ear, olfactory
* multi-polar- many dendrites, usually only one axon; pyramidal in hippocampus and perkinje in cerebellum
81
describe the beta-adrenergic receptors (locations and effects)
* **_beta-1:_**
* location- heart
* effects- +chronotropic (increased HR)
* + dromotropic effect (increased conduction velocity)
* +inotropic (increase ctx force, contractility)
* **_beta-2:_**
* location: bronchioles (2 lungs), smooth m of GI tract, bladder, and uterus
* increased respiration, decreased GI motility, decrease labor ctxs
* **_beta 3_**: adipocytes (increased lipolysis, increased uncoupling protein)
82
define somatosensory
senses felt throughout the body and some internal organs (pain, temperature, touch, pressure) as oppposed to those received only at localized special sensory organs (sight, hearing, smell, taste)
83
describe the characteristics of the 4 types of nerve fibers that transmit somatosensory information (diameter, myelination, senses conveyed)
* **A-alpha**: largest/fastest diameter, myelinated, proprioception
* **A-beta**: large/fast, myelinated, skin-pressure, touch, vibration
* **A-delta**: medium diameter, lightly myelinated, mechanical/thermal PAIN
* **C**: smallest/slowest diameter, *non*-myelinated, mechanical/thermal/chemical PAIN
84
