12-2 ASCENDING NS Pathways Flashcards Preview

NEUROLOGY > 12-2 ASCENDING NS Pathways > Flashcards

Flashcards in 12-2 ASCENDING NS Pathways Deck (12):
1

What is the Dorsal Column Pathway important for? [3]

1. Proprioception (position sense due to muscle spindle & golgi tendon receptors)
2. Vibration sense [ex. tuning fork or sitting on dryer]
3. 2 Point discrimination (stereognosis)

2

A: Describe Area 312 and Area 4

B: Explain why there is NO HEAD in the Homunculus and why Dorsal Column Pathway isn't involved with Head

C: Stroke of RIGHT Cortex wipes out Vibration/Position/2Point of the ____[Right/Left] Body! Why is this?

A: Area 312 is AKA the POST-central Gyrus for sensory info
vs.

Area 4 = AKA precentral gyrus = motor
---------------------------------------------------------------------------------
B: Homunculus for DCP has no Head becuz pain/vibration/position OF HEAD are carried out by [Trigeminal/CN5]

C: A stroke of the RIGHT Cortex wipes out Vibration/Position/2Point of the LEFT Body----> because DCP Crosses Over in the Pyramid of Lower Medulla

3

A: In Myelin Stains...Fibers are ____...and cells are _____

B: Where is the [OLIVE Nucleus] and Pyramids located? What is the significance of the Pyramids?

C: LEG SENSORY information travels via ____ ______ so it bends/enters in Fasciculus ______ to synapse in the nucleus ____

D: Dorsal Column Pathway represents ____[Conscious/UNconscious] position/vibration/2point. What pathway represents the Opposite?

E: Fasciculus are also known as _____

A: In Myelin Stains...FiBers are BLacK...and [nuclei/cells] are white

B: Squiggly [inf. OLIVE Nucleus] and Pyramids are located in the MEDULLA. Pyramids are where the [Corticospinal Motor Tract] are located

C: LEG SENSORY information travels via DCP MEDIALLY so it bends/enters in MG [MEDIAL (fasciculus GRACILIS) ] to synapse in the nucleus GRACILIS

D: Dorsal Column Pathway represents CONSCIOUS position/vibration/2point.

**DORSAL SPINOCEREBELLAR represents UNconscious position/vibration/2point

E: Fasiculus are AKA Columns

4

A: What 2 things are contained in Dorsal Root Columns

B: In [Tabes Dorsalis], ______ destroys _______ which leads to ----->ATROPHY of ________ . Pt will show positive ______ sign because they've LOST ____ from _____ RECEPTORS

A: Dorsal Root Columns = [Fasciculus cuneatus] & [Fasciculus Gracilis]

B: In [Tabes Dorsalis], Neurosyphilis destroys {DRG} DORSAL ROOT GANGLION CELLS----->ATROPHY of [Dorsal Root Columns] . Pt show positive ROMBERG sign (stomping gait) because they've LOST proprioreception from JOINT RECEPTORS

5

What are 3 signs of POSITIVE Romberg Sign ?

B: What causes POSITIVE Romberg Sign

Positive Romberg Sign <----Neurosyphilis destroying [Dorsal Root Ganglion Cells]
1. Pt requires vision to stand steady
2. [+ Sensory ATaxia] but [ - cerebellar ataxia]
3. STOMPING GAIT

6

What are 2 big landmarks of the Midbrain

1) Midbrain has 2 GIANT [Crus Cerebri Cerebrum peduncle] that make it look like upside down Micky Mouse

2) Also Has Substantia Nigra

7

1) What is Syringomyelia

2) Why Are Sacral Fibers of Spinothalamic tract usually the Last destroyed in this dz?

3) What is "Vested" Loss?

4) What 2 senses are Spared?

1) Vacuole Hole or tube forms near central canal and grows eventually transecting the cord = Syrinx

2)SACRAL Fibers of Spinothalamic Tract are more Lateral so are LAST to be destroyed by Syrinx = Sacral Sparing of Pain & Temp

3) "Vested" Loss = Syrinx wipes out STT fibers ONLY at level of CERVICAL region...and Sacral/lumbar fibers are spared

4) Proprioreception and Vibration

8

How would a Stroke of 1 Hemisphere affect the Spinothalamic Tract and Dorsal Column Pathway?

B: On a Hemisected Spinal Cord DCP will be affected ______ and STT will be affected _______. Why is this?

Stroke of 1 hemisphere would wipe out BOTH STT(cross in spinal cord) and DCP(cross in lower medulla) on OPPOSITE side because BOTH cross further down

B: On a Hemisected cord DCP will be affected IPSILATERALLY (because it crosses higher up in LOWER medulla) and STT will be affected contralaterally

9

MOST Cerebellar injury signs are _____[Contralateral/Ipsilateral]

MOST Cerebellar injury signs are IPSILATERAL

10

A: [Ventral Spinocerebellar Tracts] crosses Midline at what 2 locations?

B: What is the purpose of the [Ventral Spinocerebellar Tract]? Can this be Clinically Assessed?

C: What type of Peripheral Input does [Ventral Spinocerebellar Tract] receive?

The [Ventral Spinocerebellar Tract] crosses
1. in Spinal Cord
2. in [SUPERIOR cerebellar peduncle] before entering Cerebellum Vermis

B: samples spinal cord interneurons and relays their "state of being" to cerebellum. CAN NOT BE CLINICALLY ASSESSED.

C: DOES NOT RECEIVE ANY PERIPHERAL INPUT!!!!!!

11

What are the 6 Sensory Receptors that utilize the [Dorsal Spinocerebellar Tract] Pathway for ______ ______ ______.

5 Sensory Receptors that utilize the [Dorsal Spinocerebellar Tract] Pathway for UNCONSCIOUS IPSILATERAL PROPRIORECEPTION

MMM JRP
1. Meissner's Corpuscle
2. Pacinian Corpuscle
3. Merkels Disk
4. Ruffini
5. Joint Receptors
6. Muscle Spindles

12

Causes of Syringomyelia (3)

1. [Abnormal CSF flow/pressure 2º to malformation]
2. Tumor
3. Residual of Trauma