Spinal Cord and Periphery

Question 1

Where is grey matter found in the spinal cord?

Answer 1

Centre

Question 2

Where is white matter found in the spinal cord?

Answer 2

Around the periphery

Question 3

What composes white matter?

Answer 3

Myelinated axons

Question 4

What are the 2 horns contained in the grey matter?

Answer 4

Dorsal

Ventral

Question 5

Where do the axons of sensory fibres enter?

Answer 5

Through the dorsal route into the dorsal horn of the grey matter

Question 6

Where do sensory fibres synapse?

Answer 6

Dorsal ganglia

Question 7

Where is dorsal ganglia located?

Answer 7

Just outside the dorsal horn

Question 8

Where do motor neurons have their cell bodies?

Answer 8

In the ventral horn

Question 9

Where do motor neurons exit the spinal cord?

Answer 9

Through the ventral route

Question 10

What is the central canal?

Answer 10

Hole in the centre of the spinal cord

Question 11

What is located in the central canal?

Answer 11

CSF

Question 12

What do ascending pathways carry?

Answer 12

Sensory information towards the brain

Question 13

What do descending pathways carry?

Answer 13

Motor information away from the brain

Question 14

What 3 columns are tracts arranged as?

Answer 14

Posterior, lateral and anterior

Question 15

How many neurons are there between the peripheral receptor and cortex in ascending pathways?

Answer 15

3

Question 16

What are the 3 neurons in ascending pathways?

Answer 16

1st
2nd
3rd order neuron

Question 17

What do 1st neurons carry in AP?

Answer 17

Sensory information regarding touch, proprioception or vibration from peripheral nerves to the spinal cord or brainstem

Question 18

Where do ascending pathways first synapse?

Answer 18

Either at the level of the spinal cord

Or at the medulla

Question 19

Where do 1st order neuron cell bodies bode in AP?

Answer 19

In dorsal root ganglion

Question 20

What happens to neurons in ascending pathways at the medulla in AP ?

Answer 20

Decussate to travel in the contralateral side

Question 21

Where do 2nd and 3rd neurons synapse in AP?

Answer 21

At the thalamus

Question 22

Where do 3rd order neurons finally end in AP?

Answer 22

At the contralateral parietal cortex

Question 23

What is the function of 3rd order neurons in AP?

Answer 23

Transmit sensory signals from the thalamus to the contralateral primary sensory cortex of the brain

Question 24

Where is the sensory cortex found?

Answer 24

Post central gyrus in the parietal lobe

Question 25

What do lateral spinothalmic tracts detect?

Answer 25

Pain and temperature

Question 26

What do anterior spinthalmic tracts detect?

Answer 26

Light touch and pressure

Question 27

What do dorsal column tracts detect?

Answer 27

Deep touch and pressure | From the opposite side of the body

Question 28

Where does the posterior spinothalmic tract decussate?

Answer 28

At the level of the medullae

Question 29

What is the function of lateral spinothalmic tracts?

Answer 29

Carries information about pain and temperature to the contralateral side

Question 30

Where does the lateral spinothalmic tract decussate?

Answer 30

At the level of the spinal cord

Question 31

Where do motor tracts of the spinal cord originate?

Answer 31

In the cerebral cortex and brainstem

Question 32

How many neurons are in descending pathways?

Answer 32

2

Question 33

Where do descending pathways decussate?

Answer 33

In the brainstem | Pyramidal of the medulla

Question 34

Where do 1st order neurons in DP originate?

Answer 34

Primary motor cortex

Question 35

Does all sensory information need to be sent to the brain to make decisions?

Answer 35

No

Question 36

What is a reflex?

Answer 36

An involuntary stereotypes pattern of response brought about by a sensory stimulus

Question 37

Where are many reflexes mediated?

Answer 37

At the level of the spinal cord

Question 38

What are the sequence of events in the knee jerk?

Answer 38

1.) Tendon is stretches 2.) Muscle fibres are stimulatesd 3.) Sensory neuron is activated 4.) Monosynaptic reflex arc (not going anywhere up the tracts to the cerebral hemispheres) 5.) Polysynaptic reflex arc to inhibitory interneuron 6.) Reciprocal innervation 7.) Muscle contraction Flexion of the hit muscle Extension of the contralateral muscle

Question 39

Is UMN or LMN involved with reflexes?

Answer 39

LMN

Question 40

If there is a UMN lesion are reflexes damaged?

Answer 40

No because UMN is not involved in them

Question 41

What happens to reflexes if there is a UMN lesion?

Answer 41

They become exaggerated

Question 42

What are the 2 divisions of the PNS?

Answer 42

Somatic motor | Autonomic motor

Question 43

What are the 3 types of muscle in the body?

Answer 43

Smooth Cardiac Skeletal