Lecture 13; 9/25

Question 1

The cord transmit _____ information from the peripheries to the brain/brainstem

Answer 1

sensory

Question 2

Motor pathways are

Answer 2

Descending

Efferent

Question 3

What are the majority of efferent pathways called?

Answer 3

Pyramidal

Question 4

What are the 2 Pyramidal pathways called?

Answer 4

Lateral Corticospinal tract

Anterior Corticospinal tract

Question 5

What are the Pyramidal pathways responsible for?

Answer 5

Majority of movement

Question 6

What are the the 2 motor efferent pathways called?

Answer 6

Pyramidal tracts
Extrapyramidal tracts

Question 7

What are the 4 extrapyramidal tracts called?

Answer 7

Rubrospinal tract
Reticulospinal tract
Olivospinal tract
Vestibulospinal tract

Question 8

What are the extrapyramidal tracts responsible for?

Answer 8

Accessory motor pathways for complex tasks

we dont even know that it is happening

Question 9

What is a tract?

Answer 9

Bundle of axons within the CNS

Question 10

What is a nerve?

Answer 10

Bunle of axons outside of the CNS

Question 11

Senory is _____ and Motor is ______

Answer 11

Up

Down

Question 12

Sensory pathways are_______

Answer 12

Ascending

Afferent

Question 13

Do we have more motor or sensory pathways? Why?

Answer 13

Sensory

We have much more sensory information being transmitted through the body than motor. Ex) Pressure, temp, pain, etc

Question 14

Ascending and Descending columns are ______ bundled together

Answer 14

axons

Question 15

Where does our touch/pressure sensory gets fed up from?

Answer 15

The Dorsal Column pathways

Question 16

If our hands are up in the air, what pathway does this get fed up from?

Answer 16

The Dorsal Column pathways

Question 17

Where are pain signals relayed from?

Answer 17

Anterolateral system

Question 18

What does the anterolateral system consist of?

Answer 18

Anterior spinothalamic tract
Lateral spinothalamic tract

Question 19

Through the spine into the thalamus =

Answer 19

Spinothalamic

Question 20

How does pain signal travels?

Answer 20

Pain signals -> spine -> thalamus -> parietal cortex

Question 21

What happens in the parietal cortex regarding pain?

Answer 21

Pain is sorted

Ex) how bad is the pain, where is it coming from, how severe is it?

Question 22

Anterolateral =

Answer 22

Spinothalamic

Question 23

What is Rexed’s Laminae?

Answer 23

Ways to divid grey matter in the cord

Question 24

How is Rexed Laminae numbered?

Answer 24

Back to front

Dorsal to ventral

Question 25

What is Lamina I responsible for?

Answer 25

Fast/Sharp pain

Question 26

What is the alt name for Lamina I?

Answer 26

Lamina Marginalis

Question 27

How does the signal travel on Lamina I

Answer 27

Alpha-Delta Fibers Heavy Myelinated nociceptors

Question 28

What is Laminae II and III responsible for?

Answer 28

Slow pain

Question 29

What are Laminae II and III collectedly called?

Answer 29

Substantia Gelatinosa

Question 30

What alt Laminae is responsible for slow pain?

Answer 30

V

Question 31

How does the signal travel on Laminae II and III?

Answer 31

Non-myelinated C-fibers

Question 32

Where are Mechanoreceptors located?

Answer 32

Laminae I - VI

Question 33

What do Mechanoreceptors do?

Answer 33

Relay pressure sensory info to the areas where Laminae I-VI

Question 34

Where is Laminae I-VI?

Answer 34

Dorsal horn

Question 35

What does Lamina Marginalis mean?

Answer 35

Tip of Dorsal Horn

Question 36

How many Laminae are there in total?

Answer 36

10

Question 37

Where does crosstalk happen in the grey matter?

Answer 37

Laminae X

Question 38

Where does crosstalk happen in the white matter?

Answer 38

Anterior white commisure

Question 39

Where are the majority of large motor neurons?

Answer 39

Laminae VIII

Question 40

Why is the ventral horn bigger than the dorsal?

Answer 40

Cell bodies from multipolar motor neurons

Question 41

Where is Laminae X located?

Answer 41

In the center of the grey matter. Surrounds the central canal

Question 42

What does the Spinocerebellar tract do?

Answer 42

Bring sensory info from the spine to the cerebellum

Question 43

What is the nickname for the Dorsal-Column Medial Lemniscal System?

Answer 43

DCML

Question 44

Describe the Dorsal-Column Medial Lemniscal System

Answer 44

Major pressure sensory and touching sensitive pathway Passes through the Medial Lemniscal of the brainstem In the Dorsal part of the cord

Question 45

Spinothalamic tract =

Answer 45

Pain

Question 46

Corticospinal tracts alt names

Answer 46

Descending motor pathways Pyramidal tracts

Question 47

Where does the Corticospinal tracts originate?

Answer 47

Cerebral cortex / motor cortex

Question 48

Where is our motor cortex?

Answer 48

Pre central sulcus Frontal lobe

Question 49

Where is our cerebral cortex?

Answer 49

Most superior part of brain: Telencephalon

Question 50

Where does the Extrapyramidal tracts originate?

Answer 50

Brainstem

Question 51

The higher in the cord we go the _____ the dorsal column is

Answer 51

Bigger

Question 52

Which part of the dorsal column changes?

Answer 52

The Fasciculus Cuneatus

Question 53

What is the lateral part of the dorsal column?

Answer 53

Fasciculus Cuneatus

Question 54

Describe the Fasciculus Gracilis vs Fasciculus Cuneatus

Answer 54

Fasciculus Gracilis: Sensory pathway for muscles in lower extremities Fasciculus Cuneatus: Sensory pathway for muscles in upper extremities

Question 55

What type of fibers are used in the DCML?

Answer 55

Heavily myelinated A-fibers Alpha Beta Delta Gamma (Fine vibrations and Fine pressure)

Question 56

The Gracilis muscle is located where?

Answer 56

Leg

Question 57

Describe A-fibers

Answer 57

Very fast signaling

Question 58

Where does crossover happen in the DCML?

Answer 58

Lower part of the Medulla which is at the bottom of the brainstem

Question 59

What is the Ventrobasal Complex?

Answer 59

Part of the thalamus that runs info to the parietal lobe in the DCML pathway

Question 60

Describe the internal Capsule

Answer 60

Sits outside of the thalamus The DCML pathway passes through here AFTER going through the thalamus on the way to the cerebral cortex / parietal lobe

Question 61

Describe the pathway for DCML for a foot tickle

Answer 61

Dorsal root/spinal ganglion -> dorsal rootlets -> ascending Fasciculus gracilis -> Lower medulla oblongata -> Medulla oblongata -> Medial Lemniscus -> Ventrobasal complex of the thalamus -> Internal Capsule -> Cerebral cortex/parietal lobe

Question 62

What are the body parts affected from the postcentral gyrus by DCML pathways from anterior to posterior

Answer 62

Lower extremities Trunk Upper extremities Face

Question 63

Where are the majority of our pressure sensors?

Answer 63

Hands and Face

Question 64

Why are corticospinal tracts called Pyramidal tracts?

Answer 64

Because they pass through the pyraminds in the brain stem

Question 65

Where does the Lateral corticospinal (primary) pathway originate?

Answer 65

Cerebral corbex (frontal lobe/precentral sulcus/primary motor cortex)

Question 66

What is the pathway of the Lateral corticospinal pathway?

Answer 66

Cortex -> Internal Capsule -> Pyraminds of Medulla -> Crossover at the Pyramidal Decussation on the Medulla -> Lateral Corticospinal tract

Question 67

Where does crossover happen in the Lateral Corticospinal (Primary) pathway?

Answer 67

Pyramidal Decussaton on the Pyramids of the Medulla

Question 68

Where are the pyramids of the medulla located?

Answer 68

Ridges on the anterior brainstem

Question 70

____% of Motor signals come from the anterior corticospinal tract

Answer 70

17%

Question 71

Where does crossover happen in the anterior corticospinal tract?

Answer 71

In the spinal cord at the level where message needs to be communicated at

Question 72

What % of info doesnt get crossed over at all?

Answer 72

2-3%