Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuro Deck > Week 2 > Flashcards

Week 2 Flashcards

1
Q

Name the common patterns of neuropathy

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain vitamin b12 deficiency and its implications towards neuropathy

A
  1. B12 deficiency very prevelant amongst old people
  2. affect peripheral nerves, optic nerve, spinal cord, and brain
  3. Effects distal limbs more common in upper limb
  4. Loss of vibration sense is the most common feature
  5. affects the DCMLS and LCST subacute combined degneration
  6. Symptoms- ataxia, spasticity can occur as well as peripheral neuropathy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is polyneuropathy

A
  1. this disease is caused by a general process affecting the peripeheral nerves.
  2. Presents as Distal and symmestrical sensorimotor(ANS maybe) distribution
  3. Follows stocking and glove pattern because it primarily impacts distal nerves
  4. Common causes are, Diabetes, alcohol, hypothyrodism, and Vitamin B12 deficiency. Also patients in ICU
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

List the different presenting symptoms of neuropathy of all the fiber types

A
  1. Peripheral nerve- includes all fiber types, loss of sensory, motor and autonomic symptoms
  2. Small fibers- pain, temp, and autonomic loss
  3. Myelin(Large fibers)- vibration and position sense loss with motor loss.
  4. Sensory ganglion lesions- only sensory symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain Apperceptive Agnosia more in depth

A
  1. Patient is able to react to visual stimulus but it not able to combine the image into a meaniful message.
  2. Basically the V1 assembly pathway is fully functional but V2/V3 pathway that intergrates form and shape is not working.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A superior left homonymus quandrantanopisia is causes primarily by what and explain

A
  1. Pituitary adenoma in the right Optic tract or meyers loop depending on the presentation.
  2. First of all it has to be on the right because the right side of the brain carries left vision and this is a left homonymus
  3. It primarily should be a pit adenoma because the pit runs inferior to the superior fibers. +Superior fibers are located on the bottom and inferior fibers are located at the top
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When do we use a CT

A
  1. Intracranial hemorrage
  2. acute trauma and shocj
  3. Stroke imaging
  4. Fractures
  5. Sinusitis
  6. Bone lesions
  7. Dental imaging
  8. Myelography
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A lesion of the posterior cerebral artery branches supplying the lingual gyri sparing the ocipital pole would present as

A
  1. A lesion to the right occipital lingual gyri would present as

Left homonymus superior quandrantanopia with macular sparing

Lesion is unilateral because occipital pole is spared

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are some causes of non traumatic peripheral neurpathies

A
  1. Diabetes Mellitus 2
  2. Vitamin B12
  3. Guillian Barre
  4. Charcot Marie tooth neuropathy- Genetic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Visualize all of the spinal pathways and their connects

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which parts of the brain are repsonsible for attention, tactile learning and memory

A
  1. Posterior parietal+ motor cortex= attention
  2. Secondary somatosensory cortex+ limbic system for tactile learning and memory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Summarize the basic organization and function of the visual cortex

A
  1. V1 recieves and organizes the information sent from the LGN center. Also responds to movement and color.
  2. V1 then sends this partially organized info to the higher visual cortexes which decide form, color, and motion.
  3. After this has been identified the information must be then compared to memory to identify this is done at the fusiform gyrus bilateral damage to this can cause facial blindness aka Prosopagnosia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the spinocerebellar tract and where is it located

A

This tract is basically responsible for proprioception for large motor neurons

  1. Posterior- lower limbs ispisilateral to the cerebellum
  2. Cuneocerebellar- upper limbs and ispislateral to the cerebellum
  3. Anterior- lower limbs(interneurons) also same side as the cerebellum
  4. Rostral- upper limbs same ting as before
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

A lesion to the posterior cerebral artery supplying the lingual gyri would present as what

A
  1. Binocular altitudinal scotoma
  2. The lesion here is bilateral because it inlcudes the occipital pole
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the pathological manifestations of B12 def

A
  1. You need B12 in order to make myelin
  2. Looks similar to MS
  3. give patients B12

Loss of vibration, touch, and position sense

(+) Romberg sign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define the major characterisitics of each type of sensory receptor

A

Proprioception- muscle spindle-Fatest, afferent Ia, II

touch, AB- medium fast

  1. Meissner- just below skin, surface and motion
  2. Merkels disc- edges and indentations
  3. Ruffini corpuscle- skin stretch
  4. Pacinian Corpuscle
    - vibration

Pain temp

**Nocireceptors are just free nerve endings and they are at the surface of the skin- Slowest- Alpha delta and C fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the major blood suppliers to the DCLMS and STT in the spinal cord and Cortex

A

Spinal DCLMS-Posterior Spinal artery

Spinal STT- Anterior Spinal artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the symptoms of neuropathy

A
  1. Weakness and muscle atrophy
  2. loss of reflexes
  3. Loss of sensation
  4. Abnormal sensations(tingling burning)
  5. Pain
  6. Autonomic changes (sweating, heart rate, vascular)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which vision is impacted by glaucoma first and why

A
  1. Peripheral vision becuase the axons there are the thinnest
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the role of Opsin in shutting off rods and cons

A
  1. Light turns retinal(vitamin A) from cis to trans which causes the actual opsin protein to interact with G protein and turn on a signaling cascade.
  2. Then opsin interacts with transducin which then activates the PDEs
  3. PDEs then cleave CGMP to turn off the ion channle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Name all the visual cortex regions and their associated lesions

A

V1- all inputs coritcal blindness

V2/V3- Form and Shape Apperceptive Agnosia (patients can see and object but they cannot draw or explain what it is but when you ask them to draw a “key” forexample they can but not from visual stimulus

V4- Color Achromatopsia

V5- Motion- Akinetoposia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

A Lesion to V5 would cause what type of visual defect

A
  1. Akinetopsia (motion blindness)
  2. Static objects are clearly visible but once they start moving the patient is unable to see them
  3. Patients also cant tell the direction an object is moving
  4. This lesion typically doesnt effect other visual processes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Metabolic disease cause what to happen to axons

A
  1. Metabolic diseases damage the health of the neuron and cause Dying back of axons
  2. Axons lose myelin
  3. Affects longer first so neuropathy is more likely to be seen in distal extremities

***DM2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What causes Tabes Dorsalis and Subacute combined degeneration of the dorsal columns

A
  1. Tabes dorsalis is caused by tertiary syphillis infection- degenerneration of dorsal colums causing loss of sensation and proprioception. Progressive sensory ataxia
  2. Subacute combined degeneration is caused by Vitamin B12 or E deficiency. Causes dymeylination of dorsal colums LCST and spinocerebellar tracts causing ataxic gait, paraesthesia, impaired position and vibration sense.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Axonal damage to a peripheral nerve causes what

A
  1. Wallerian Degeneration aka dying foward
  2. Distal axonol degerneration usually caused by some trauma
  3. Chromatolysis of cell body ( nucleolus expands)
  4. Recruit macs

**There is hope the proximal stump can regenerate 1-2mm per day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Explain segemental dymelination and its causes will there be muscle atrophy and why or why not

A
  1. Segmental dymelination occurs when myelin sheaths are damaged by trauma or disease
  2. Demyelination are detected by nerve conduction tests conduction block, slow CV
  3. The myelin can grow back in a dew days or weeks.
  4. no because axon and cell body is undamaged muscle is still innervated. Conduction maybe slowed but thats about it.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How are rods turned off when they are exposed to light

A
  1. Optic disc receives light signal decreases amouth of glutamate
  2. Causes CGMP to dissociate from the ion channel which turns off the sodium influx pushing the cell into hyperpolirization

So basically by reducing CGMP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Name all the major features of Diabetic Neuropathy

A
  1. 2% of pop
  2. 16% of diabetics have neuropathic pain
  3. Greatest source of morbidity and mortality for diabetics
  4. Cause of 50-70% of amputations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Macular degeneration is most commonly caused by what

A
  1. Fatty deposition behind the retina(dry) or neovascularization (wet macular degeneration)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What determines resolution of a stimulus

A
  1. Receptive fields- which basically the area in which a stimulus elicits the greatest AP responce
    - Allows body to tune out irrelevant inforamtion and focus on distinct objects.

**so if i just got stabbed in my arm i would focus on my wound instead of the shirt Im wearing

32
Q

Describe the somatopic organization of the DCMLS

A
  • Fasiculus cuneas gives information about the upper limbs of the body and is located more laterally on the white matter of the spinal cord same in the cortex
  • Fasiculus gracillus- gives information about the lower limbs and is located more medially on the spinal cord same with the cortex.
33
Q

What is the diagnoses of the patient who present with a neck laceration with left sided numbess and right sided loss of pain and temp response

A
  1. Hemisection of the left side of the spinak cord aka Brown Sequard syndrome.
  2. Injury to the right STT and left DCLMS
  3. Causes dissociated sensory loss.
34
Q

Explain the entire spinothalmic pathway from root to cortex and explain its function

A

Conveys, Pain Temp and Crude touch from nocireptors for the body

  1. Enters the dorsal root ganglion at Lissauer’s Tract
  2. Takes two segments to cross the Anterior White Commissure then stops at the anterolateral pathway
  3. Then it acends on the contralateral side all the way up to the cortex where it synapses again at the Ventral Post lateral nucleus of the thalamus
  4. Fomr there it terminates at the post central gyrus of the somatosensory cortex
35
Q

Which area is impacted by age related macular degeneration

A
  1. The fovea and its lateral to the optic disc

****Fovea area of high visual aquity cones only

36
Q

What is the parvocellular cascade and what is the magnocellular cascade

A
  1. Parvo= where is it Spatial resolution These are activated by fine visual detail and color. Discriminate objects
  2. Magnocellular= Where is it going Temporal resolution. These are activated by a large stimulus. These are the bigger cells so movement gets to the CNS faster than fine detail
  3. Form and color come from the visual cells
37
Q

Explain the morphology and fxn of propriorecptors

A
  1. They are located within the muscle and are part of the golgi tendon and muscle spindle. They detect joint position and sense.
  2. Muscle spindle- muscle tension
  3. Golgi Tendon- muscle tension
38
Q

What is Charcot marie tooth disease

A
  1. Group of heriditary diseases that either affect myelin CMT1 or axons directly CMT2
  2. CMT1>CMT2
  3. CMT1 produces motor and sensory probz. Affects mostly distal muscle especially peroneal nerve
  4. Because this is a demyleninating disorder small fiber types carrying pain and temp are not affected
  5. Seen with Pes Cavus and Hammertoes
  6. Starts in late childhood and is slowly progressive

***Reduction in conduction velocity

39
Q

List all the major tests for dermatomes

A
40
Q

How to diagnose GB

A
  1. Symptoms usually appear after an infection or vax
  2. Protein in CSF but no increase in cell
  3. Electro test show decrease in conduction velocity
41
Q

Is the response for photoreceptors graded or all or none

A
  1. The response is graded because our eyes need to adapt to the different gradiations or light.
  2. More light= less glutamate Less light=more glutamate
  3. It all depends on light and intensity
42
Q

Guillain Barre

A
  1. aka Acute inlammatory demyelinating polyneuropathy
  2. Most common cause of acute neuropathy and death
  3. Motor>>>Sensory with ascending paralysis
  4. Parestheisias(Burning) in finger and toes that progresses to the thighs and back
  5. Eventually leads to respiratory arrest
  6. Nerve conduction is decreased

7. Increased protien in CSF normal cell count

43
Q

Explain the differences in presentation of lesions on the spinal and cortex in terms of the DCLMS and STT

A
  1. Lesion within the spinal cord will result in the dissociation of the injury to both sides of the body. One side losing touch and the other losing pain.
    - Because STT is contraleral it crosses at the anterior comissure so on the left will be the STT afferent from the right and vice versa
  2. Now a lesion at the Medulla will only present on one side*** of the body and it will be ***Contralateral because by that point the DCLMS would have crossed at the internal arcuate fibers. So a lesion to the left side of the medulla will present with loss of touch and pain to only the right side of the body
44
Q

What is the macula and damage to what part of the cortex causes loss of macula vision

A
  1. Macula is the larger region of visual acuity that includes the fovea. Damage to this part causes macular degeneration which is bascially loss of central vision
  2. Lost to the occipital pole will cause Controlateral homonymus macular vision loss
45
Q

Give a basica summary of rods and cones and there fxns as light axons

A
  1. Rods= night vision and motion vision
  2. Cones= color vision, stationary object recognition, the brighter the visual field the better the recognition.
  3. The fovea= what the fuck is that and what color it is

***The neurotransmitter for photoreceptors is always glutamate. They don’t have axons or action potentials

46
Q

Explain the mechanism by which the nervous system encodes sensory stimuli

A
  1. Modality-processes diff types of stimuli via various receptors and labeled tracts
  2. Intensity- strength of the stimulus diff receptors have different sensitivites
  3. Timing- receptors fire at different times and diff speeds for diff stimuli. They basically adapt very quickly
  4. Location- basically where on the body the stimuli is located will affect how the body encodes the info
47
Q

What causes Gullian Barre

A
  1. infection or vaccine, symptoms appear in 1-3 weeks
  2. Campylobacter jejuni or HSV
  3. Infection causes AI response/inflamatory attack on peripheral myelin
48
Q

Describe the somatropic organization of the spinothalmic pathway

A
  1. Upper extremenity is located more medially as compared to lower extremnity but I guess when it crosses the anterior white commissure this flips because.
  2. Lowe extremenities are located more medially in the cortex.
49
Q

When do we see muscle atrophy with nerve injury

A
  1. Wallerian degeneration caused by trauma axon is damaged
  2. Axonal degeneration

***Both cases axon is damaged so muscle in denervated LMNS

50
Q

Mononeuropathies and plexopathies are caused by what

A

lesions to specific nerves or plexuses and they are Focal lesions

Usually caused by trauma

51
Q

Describe the pathway of the trigeminal mechanosensry system and what does it do

A

Conveys touch and vibration, proprioception of the jaw sensation from the face to the cortex

  1. Mid-pons trigeminal nerve synapses at the Principle nucleus of the trigeminal complex
  2. The second afferent crosses the medial lemniscus travels up the midbrain as the trigeminal lemniscus
  3. Synapses in the thalamus at the ventral posterior medial nucleus of the thalamus
52
Q

Explain the pathophysiology of diabetic neuropathy. Which neurons are more likely to be affected

A
  1. All 3 types of axonal degeneration can occur
  2. Symptoms are causedd by ischemia, oxiadative stres, and inflamatory processes
  3. Sensory neurons are more likely to be affected than motor.
  4. Often referred to as Small fiber neuropathy
53
Q

Describe lesions to the spinocerebellar tracts

A
  1. Present on the same side as loss of msucle cordination.

****These tracts are unlikely to be damaged by themselves. DCMLS and STT are also likely to be damaged as well.

54
Q

Describe the trigmenial pathway for pain and temp perception on the face

A
  1. Enter via either the caudal medulla or th middle medulla
  2. Synapse at the spinal trigeminal tract
  3. Travel up the brain stem to the thalamus and synapse at the Ventral posterior medial nucleus of thalamus
  4. Terminate at the cortex
55
Q

Give two examples of focal lesions

A

Radiculopathy- Herpes Zoster arising from DRG at T1 causing tingling and burning at that dermatome. Usually just sensory unilateral

Mononeuropathy- Carpal tunnel, these types of lesions effect Sensory, motor, and autonomic fxn*** because this involves they entire nerve not the just the DRG ***unilateral

56
Q

Explain the diff btwn Neuropathic pain and nociceptive pain and treatment

A
  1. Nocieceptive pain is pain in which tissues are damaged but nerves are not necessarily affected
  2. Neuropathic pain comes from the PNS or CNS
  3. Characterized by burning, shooting, stinging pain mixed with areas of numbness
  4. May also have sponataneous pain and increase sensitivity to pain
  5. Depression*** is a common feature of neuropathic pain treat with ***antidepressants and anti epileptic drugs
  6. Herpes Zoster and Trigeminal neuralgia
57
Q

What is two point discrimination

A
  1. Neuro test used to see how well a patient can percieve two simultaneously applied stimuli *Spatial resolution
    - smallest distance on fingers, largest on shoulder and forhead.
    - so basically the more receptors you have in an area i.e fingers the more resolution you have and the more info you can send to the brain.
58
Q

Case

21 y/o presents with neck laceration on left side of neck and is experiencing numbness on left side of body below C5 and no pain on no pain sensitivity on the righ side Below C7

rationalize this case

A
  1. Loss of touch and vibration on the left side signals damage to DCLMS on the left
  2. Patient also lost proprioception on the left which signals damage to the spinocerebellar tract on the left

****these two tracts dont cross until after they leave the spinal cord and since this patient isnt experiencing any facial symptoms we can assume this is a spinal cord injury so it must be on the left

  1. Loss of pain and temp below C7 on the right side so this must be injury to the STT on the left at C5

**stt is contralteral its moves across the spinal cord at the anterior white comissure. So a laceration on the left will present two segments below on the right

59
Q

photoreceptor cell cascade

A
60
Q

What can cause b12 deficiency

A
  1. Vegeterinanism and Veganism
  2. Gluten free people and people with malabsorption
  3. Patients with B12 def may also have pernicious anemia
61
Q

What is feature detection and how do we use it as a diagnostic tes

A
  1. Principle cortical processing that allows brains to find a common pattern to stimuli (so basically see with our hands)
  2. Stereognosis- simply place object into hand
  3. Graphesthesia- draw a shape into the hand

**If patient and feel the object but cannot identify it this indicates problems with the cortex. Sensory info by the afferents is being relayed but the brain can’t process it

62
Q

What is Leng dependent diabetic neuropathy

A
  1. Causes 80% of DMNP
  2. Symptoms start in feet and move proximal and in the upper limbs move from proximal to distal.
  3. Symptoms paresthesias, dysesthesias, numbness, tingling, and burning. Motor weakness in distal limbs
  4. Calluses and plantar ulcers.
63
Q

Describe peripheral nerve pathology in patients with diabetic neuropathy

A
  1. Peripheral nerve fasicles show
    - decreased nuber of myelinated and unmyelinated axons
    - thickening of the walls of blood vessels
64
Q

What is a mononeuropathy

A
  1. Symptoms of neuropathic pain follow a peripheral nerve exclusively

***often caused by trauma

these are called Focal Lesions

65
Q

The Peripheral nervous system includes

A
  1. Spinal nerves
  2. Nerve plexes
  3. Peripheral nerves
  4. Cranial nerves
66
Q

On a CT explain hyperdense, hypodense, isodense, and mixed density

A
  1. Hyperdense= very bright, Bone and Calcifications
  2. Hypodense= fluid and fat
  3. Isodense= brain tissue
  4. Mixed density is a mixture between bone and fat
67
Q

Explain the Dorsal Colum Medial lemiscus pathway

A

Modality- Deep/fine touch, proprioception, vibration, and pressure

  1. Mechanorecptor from lower body- Fasiculus Gracilus Upper Body Fasiculus cunateus Spinal cord
  2. Caudal Medulla decussate at the interal arcuate fibers
  3. Ascend the medulla as the Medial leminscus and synapse in the thalamus at rhe Ventral Posterior Lateral Nucleus of the thalamus
  4. Terminate at the post central gyrus of the Somatosensory cortex
68
Q

What is so important about the pigment epithelium

A
  1. Site of detached retina if not reattched can lead to degeneration
  2. Important for delivery nutrients to photoreceptors
  3. Also important for removing heat and contains Melatonin
69
Q

Visualize the three types of degeneration and there effects on the muscle

A
  1. Wallerian- trauma, atrophy
  2. Segmental- trauma or disease
  3. Dying back- disease, atrophy
70
Q

Describe the histological pathology of CMT1

A
  1. fewer number of myelinated axons in the peripheral nerve
  2. Myelin tries to regenerate itself so you will see lots of thick “onion ring” bands on cross
71
Q

What are dermatomes list the major dermatomes

A
  1. Area of the skin innervated by a singe dorsal root
  2. Dermatomes may overlap since manydifferent axons can insert into the DRG
  3. Not uniform for everyone
72
Q

What is radiculopathy

A
  1. when pain symptoms follow a nerve root pattern basically the dermatome
  2. Often caused by HNP
73
Q

Name the three major pathways and their sites of decussation

A
  1. CST- Pyramids(spino-medullary jxn)
  2. DCLMS- internal arcuate fibers(medulla) **damage to the cortex will produce injury to the oppside of body
  3. Spinothalamic tract (anterior commissure) **injuries in spinal cord always appear two segments below on the opposite side
74
Q

Explain the characterisitcs of lesions in the DCMLS, Spinothalmic and Spinocerebellar pathways

A
75
Q

A patient with a lesion to V4 will most likely present with

A
  1. Cerebral bilateral Achromatopsia or unilateral
  2. Basically the lost in the ability to see color
76
Q

Explain the pathophysiology of tongue deviation

A
  1. CN12 hypoglossal nerve which is found in the pons.
  2. in patients with strokes the deviation is always on the controllateral side so a patient with a left cortex stroke would have right tongue deviation.
  3. The deviation is always towards the side of the weakness.

Deviation was always to the side of the limb weakness. In patients with a history of stroke, it occurred more frequently in those with previous stroke on the contralateral side. Tongue deviation was most common in patients with clinical features of the non-lacunar stroke subtype (56%) or in those with cortical or large subcortical infarctions on brain CT scan (55 and 45%, respectively)

77
Q

What’s the difference btwn a plegia and a paresis

A

paresis= partial paralysis

plegia= full paralysis

Neuro Deck (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions