Unit 2 Overview Flashcards
(72 cards)
1
Q
X- ray
A
2-D imaging
Fast/Cheap
- Good for fractures, pneumonia, intestinal blockages
2
Q
CT
A
- First line of defense
- good for acute stroke
- Tolerates metal implants
3
Q
MRI
A
- T1= gray vs White matter
- T2 better for pathology
- no radiation exposure in MRI
- Longer process 30-90 minutes
4
Q
T2 Flair
A
Useful for looking at plaques
Deeper imaging with thinner slices
5
Q
DWI (Diffusion imaging)
A
Mainly used for ischemia, tracks water movement
- oncology
6
Q
DTI (diffusion tension imaging)
A
Measures how water diffuses across bundles of axons
7
Q
gastrulation
A
- When the egg and the sperm meet making a zygote
- Days 14-21 embryonic phase
- WEEKS 2-20 are most concerned for structural CNS information because that where all the brain development and differentiation happens
- WEEKS 20-30 we worry more about the vascularization of the brain, intracranial hemorrhage
- embryo becomes a fetus at week 8
- Ectoderm gives rise to CNS
8
Q
Ectoderm-
A
Skin and nervous system
9
Q
Mesoderm-
A
Muscle bones reproductive kidneys
10
Q
Endoderm-
A
Endocrine glands, lungs, liver
11
Q
Electroencephalography
A
electrical activity of the brain
Seizures
12
Q
Somite
A
- Dermatomes, myotomes, sclerotomes
- Form right around the SC as it develops
Sclerotomes differentiates into bony encasements of spinal columns - Myotomes give rise to skeletal muscle
- Dermatomes gives rise to skin
13
Q
Neurulation
A
- Pre-embryonic up to week 2
- Thickening of ectoderm that forms neural plate
- Two neural folds comes together at day 21, forming neural tube
- Neural crest becomes PNS
Neural Tube becomes CNS
Embryonic event days 18-28
Plate–> folds–>groove–> tube
14
Q
White Ramus Communicans
A
- Convey preganglionic fibers of sympathetic system
- T1-L2
15
Q
Gray Ramus Communicans
A
- Convey postganglionic fibers of sympathetic system
- Above T1 and below L2
16
Q
How many total spinal nerves?
A
31 spinal nerves
17
Q
Where does the first spinal nerve exit?
A
above C1
18
Q
Where does C8 exit?
A
Below C7
19
Q
Where do afferent signals come in through?
A
Dorsal root
20
Q
Where does efferent motor signal go out of ?
A
Ventral root
21
Q
Somatosensation: 4 types
A
- Romberg Sign
- Kinesthesia
- Cerebellar Ataxia
- Sensory Ataxia
22
Q
Romberg Sign =
A
Feet together, arms crossed, eyes open for 30 seconds
- Repeat with eyes closed
- Sharpened romberg= heel to toe
23
Q
Kinesthesia
A
Moving the pt’s extremity with their eyes closed and asking if you’ve moved them up or down
its where you are in space
24
Q
Cerebellar Ataxia
A
- falling over
- walk with a wide base of support and can’t put feet together
25
Sensory Ataxia
- diabetes- peripheral neuropathy
- Stocking glove syndrome= numbness and tingling that begins in fingers and toes and moves proximal
26
Ruffini
Slow stretch/pressure
inside joint
27
Merkel
Slow touch/pressure/texture
General touch
28
Pacinian
Fast
Pressure around joint , vibration, acceleration , deceleration
Deep in the dermis
29
Meissner
Fast, fine/light touch
Eyelids or finger tips
2 point discrimination
30
Peritrichial
Free nerve endings around base of hair follicle
Response to hair movement
31
Nociceptor
pain receptors
32
A and B fibers =
Myelinated
Fast
Sharp
33
C fibers=
Unmyelinated
Dull
Slow
Associated with chronic pain
Postganglionic autonomic sympathetic fibers
34
T/F the Dorsal column medial lemnisci tract is extremely fast
true
35
Gamma is
Free nerve ending receptor
- Motor innervation to muscle spindle ***
- excitatory
36
Alpha motor neuron
Somatic to muscle
- 1A- muscle spindle receptors stimulated by muscle stretch
- Quick stretch- while muscle is moving
- 1B- GTO and ligament receptors stimulated by tension in tendon or ligament
37
Type II fibers
Static passive movement / info about muscle length
38
Alpha- Gamma coactivation
they activate at the same time
Alpha-gamma coactivation ensures that muscle spindles maintain sensitivity to stretch over a wide range of muscle lengths
39
Are alpha motor neurons intrafusal or extrafusal
Extrafusal
40
Gamma motor fibers
Intrafusal
Innervation to maintain muscle tone with spindle
41
What does the muscle spindle detect?
Muscle length and rate of velocity
- Protective mechanism
42
The GTO
Golgi Tendon Organ
1. Increased tension stimulates sensory receptor (tendon)
2. Sensory neuron is excited
3. within integrating center (spinal cord) sensory neuron activates inhibitory interneuron
4. Motor neuron inhibited
5. Effector (muscle attached to same tendon) relaxes and relieves excess tension
43
During GTO which tendon is being activated or overstretched most?
The tendon nearest to the joint
44
Monosynaptic Reflex
(deep tendon reflex)
1. Begins intrafusal muscle fibers ( afferent) responding to stretch
2. Impulse goes to dorsal root ganglion then to the ventral horn
3. Alpha motor neuron exits ventral root
4. signals NMJ while an action potential of the same muscle
IF LOWER MOTOR NEURON LMN IS INVOLVED= REDUCED REFLEX RESPONSE
IF UPPER MOTOR NEURON UMN IS INVOLVED = EXAGGERATED REFLEX RESPONSE DUE TO LOSS OF DESCENDING INHIBITION
45
what is Clonus/hyperreflexia
Clonus is you pull up the foot and hold and the foot will beat
sustained clonus= significant brain damage UMN lesion
46
What is a normal DTR?
2+
47
Reciprocal Innervation Inhibition
Bicep muscle activated and the triceps inhibited to allow for fine tuning of movement
- Antagonist muscle inhibition
- In stroke pts synergy presentation is present when UE is flexed and folded by the chest
- lack of fractionation
48
Fractionation
allows us to move segments of our bodies in isolation
49
Synergy
Move muscles as a group
Can't individualize muscle movement
50
Dorsal Column Medial Lemniscal Pathway
- What we are testing when looking at romberg
- 2 Point discrimination, fine touch, conscious proprioception
- 1st order neuron: Travels to DRG and splits to different nucleus based on whether sensation is from UE or LE: from receptor signal travels to dorsal root ganglia synapses to spinal cord and synapses either to fasciculus cuneatus (upper extremity)and/or fasciculus gracilis (lower extremity)
- 2nd order neuron from either travels across/decussates at the pyramids of the medulla, travels through the brainstem and synapses in the thalamus specifically the VPL nucleus
- 3rd order neuron: from the VPL of the thalamus through internal capsule to the primary cortex of the post central gyrus
51
Anterolateral tract
- Spinothalamic tract, Ascending Afferent Pain pathway
- 3 order neuron pathway
- Ascending = afferent
- Pain nociceptors to dorsal root ganglion then to dorsal horn (second order)
- Crosses immediately to the anterior white commissure
- Using A fibers(Fast, sharp, myelinated) and C fibers(unmyelinated, slow, ache)
52
Gate control theory of pain
1st order neuron substantia gelatinosa- where the 1st order neuron meets the 2nd motor neuron to release substance P across the synaptic cleft --> substance P stimulates the second order neuron to propagate the action potential up the spinothalamic tract to VPL
- At the thalamus and medulla ther are descending inhibitory neurons that travel down with serotonergic and noradrenaline neurons releasing both of these chemicals in the synaptic cleft WHICH WILL INHIBIT SUBSTANC EP AND INHIBIT POST SYNAPTIC NEURON ASCENDING PATHWAY
Substance P is inhibited in this pathway
53
Long Term Potentiation LTP
Silent to active synapse
- Simultaneous firing
- Mg leaves NMDA receptor
- Ca enters through NMDA glutamate receptors
- Causes AMPA receptors to go to the surface of the membrane
- Binds to glutamate to strengthen synapses
54
Long Term Depression
Active to silent synapse
- Acts on hippocampus
- Makes synaptic terminal less efficient
- Ca enters but not enough to depolarize
- AMPA receptors are removed post synaptic membrane
55
Axonotmesis
- can regenerate
- Crush injury but can be healed
- Grow 1mmper day
56
Neurotmesis
Complete severance
57
Neuropraxia
can regenerate from stretch
58
Pain is a
Disease
59
Sensitization
- increases in reaction to stimulus after repeated exposure
- After repetitions increase, pain increases
60
Habituation
- Decreased sensitivity to stimulus
- "White noise" --> this stimulus keeps occurring and you get used to it and tune it out
61
Central Sensitization
- Generally is an excessive responsiveness of central neurons
- CRPS
- Migraines --> 15 headaches in 1 month --> unilateral pain, photosensitivity, nausea, vomiting --> typically brought on by a great deal of stress
62
CPRS 1
- Complex regional pain syndrome
- Nociceptive pain that will occur after trauma or injury
63
CPRS 2
Nerve trauma
Neuropathic pain
64
Nociceptive pain
Pain with tissue damage
65
Nociclastic
Pain that comes from altered pain response with no clear tissue damage
66
Hyperalgesia 1
Excessive sensitivity to touch/pain in affected tissue
67
Hyperalgesia 2
Excessive sensitivity to touch / pain with uninjured tissue
68
Paresthesia
Absent response to touch or nociceptive response
- presents as tingling/pins and needles
69
Neuropathic pain
Neural pain from somatosensory system
70
Allodynia
Sensation of pain that does not match the input
71
Wallerian Degernation
Cell body of the nerve detracts and pulls away when there is neurotmesis or severance of spinal cord
- Happens in PNS and CNS
72
Spinal cord injury is UMN or LMN issue
UMN
