Ascending tract

Question 1

Where is white matter largest in the spinal cord?

Answer 1

Superiorly- gets smaller as cord descends

Question 2

Which matter of the sc does the nuclei reside?

Answer 2

Gray matter

Question 3

Areas where white matter enlarges?

Answer 3

Cervical enlargement: Brachial plexus, upper limb C5-T1

Lumbar enlargement: L2-S2, lumbar plexus, lower limb

Question 4

Lateral motor neurons innervate

Answer 4

Limbs

Question 5

Medial motor neurons innervate

Answer 5

Trunk

Question 6

What segment level does the spinal cord get smaller due to no innervation

Answer 6

T1-L2

Question 7

Cell Types:

In ventral horn

Major motor neuron and is a lower motor neuron that goes to muscle

Answer 7

Alpha

Question 8

Cell Types:

In ventral horn

Part of stretch receptor

Answer 8

Gamma

Question 9

Cell Types:

In ventral horn

Communicates with cells in the spinal cord on different sides

Answer 9

Propriospinal

Question 10

Cell Types:

In Ventral Horn

Carry message from one part of CNS to another

Answer 10

Relay Neurons

Question 11

Cell Types:

In Ventral horn

Separation of gray matter

Answer 11

Lamina of Rexed

Question 12

Psuedounipolar neurons that have centrifugal and centripetal branches

50,000 from T1-L2

100,000 from C5-T1 & L2-S2

Sensory

Answer 12

Dorsal root ganglia

Question 13

Dorsal root ganglia branch that goes away from CNS to receptor

Answer 13

Centrifugal

Question 14

Dorsal root ganglia branch that goes towards the CNS

Answer 14

Centripetal

Question 15

Sensation that is only perceived when it is perceived by cerebral cortex

Answer 15

Conscious sensation

Question 16

Classification of stimuli

Answer 16

Exteroception

Proprioception

Question 17

Conscious Exteroception stimuli

Answer 17

Vision
Hearing
Touch
Pressure
Heat
Cold
Pain

Question 18

Conscious Proprioeption function

Answer 18

Position sense

Kinesthetic sense

Question 19

Sensation that is not perceived because it doesn’t reach the cerebral cortex

Answer 19

Unconscious sensation

Question 20

Unconscious propriocetion

Answer 20

Motor coordination-mostly reflexive

Question 21

Unconscious enteroception

Answer 21

Visceral Reflexes-acidity, pH, etc

Question 22

Somatosensory pathways are primarily__________

Answer 22

exteroceptive

Question 23

Somatic sensory pathway rules

Answer 23

1. First order neuron is in DRG
2. Second order neuron’s cell body is
   ipsilateral but fibers cross into contralateral thalamus
3. Third order neurons projects into the postcentral gyrus (sensory cortex)

Question 24

Somatic sensory pathways are Somatotopic.

What does that mean

Answer 24

Ability to map body part function on pathway

Question 25

Somatic sensory pathways are modulated by interneurons, especially _________

Answer 25

Reticular formation

Question 26

Dorsal Column-Medial Lemniscus-Function

Answer 26

Proprioception Discrimminative touch/ Epicratic touch Vibration

Question 27

Dorsal column medial-Lemniscus refers to

Answer 27

Gracile and Cuneate fascicle that run up sc in end in medulla

Question 28

What path do the gracile and cuneate fascicle of the dorsal column medial lemnicus pathway take

Answer 28

1st order- from DRG 2nd order- synapse in cuneate nucleus and gracile and ascend up brainstem to thalamus 3rd order- ends in ventral posteriolateral nucleus in the thalamus

Question 29

The fibers of the the dorsal column -medial lemniscus cross into the medulla. What are the crossing fibers called?

Answer 29

Internal arcuate fibers

Question 30

What are the tracts involved with the dorsal column -medial lemniscus pathway?

Answer 30

Gracile fascicle Cuneate fascicle Corona Radiatia

Question 31

Once the fibers of the DCML cross, what do they do?

Answer 31

Ascend up brain stem

Question 32

When are the fibers of the DCML called medial lemniscus ?

Answer 32

As they ascend up brainstem

Question 33

Where do the fiber go after the leave the thalamus?

Answer 33

Travel post central gyrus (somatosensory) Fibers are called internal capsule and then corona radiata

Question 34

What are the fibers of the DCML leaving the thalamus called?

Answer 34

Internal capsule

Question 35

After internal capsule fibers pass the basal ganglia what are they called?

Answer 35

Corona radiata

Question 36

How many pathway are in the anterolateral system?

Answer 36

Spinothalamic Spinoreticular Spinotectal Spinoolivary

Question 37

What is the function of the anterolateral system?

Answer 37

Pain Temperature Crude touch

Question 38

ALS: Spinothalamic region responsible for noxious(pain) and temperature

Answer 38

Lateral

Question 39

ALS: Portion of spinothalamic tract responsible to light touch?

Answer 39

Anterior

Question 40

ALS: Spinothalamic pathway

Answer 40

1st order- DRG 2nd order- synapse in lamina I️, IV, V (sometimes III) 3rd order- into ventral posterolateral of the thalamus

Question 41

Tracts of the spinothalamic

Answer 41

Anterolateral system Also called spinal lemniscus only as it goes through brainstem

Question 42

Fibers of the spinothalamic pathway decussate over where?

Answer 42

Anterior white commissure - Lateral- 1 segment (spinal nerve segment) - Anterior- over several segments (2-3) (spinal nerve segment)

Question 43

Spinoreticular (Paleospinothalamic) Pathway

Answer 43

DRG —> Lamina V, VI, VII —> some fibers decussate and some don’t, there is no somatotopography—> ascend bilaterally into reticular formation

Question 44

Spinoreticular function

Answer 44

Awareness Emotion of sensation such as pain

Question 45

Cerebellar Tracts: Unconscious proprioception From Lower body DRG—>Dorsal Nucleus of Clarke/Dorsal thoracic (VII) T1-L2—> Posterior spinocerebellar tract—> inferior cerebellar peduncle into cerebellum

Answer 45

Posterior spinocerebellar

Question 46

Cerebellar tracts: unconscious proprioception Upper body - Dorsal Root ganglion -Ascend through cuneate fascicle – second order - accessory cuneate nucleus – inferior cerebellar peduncle in cerebellum

Answer 46

Cuneocerebellar

Question 47

Cerebellar tract: The reflex arcs

Answer 47

Anterior spinocerebellar Rostral spinocerebellar

Question 48

Cerebellar tracts: Reflex arc for lower body Fibers are crossed unlike other cerebellar tracts Exit in superior cerebellar tract

Answer 48

Anterior cerebellar

Question 49

Cerebellar tract: Reflex arc of upper body Fibers are uncrossed Exit in superior and inferior peduncle to cerebellum

Answer 49

Rostral Spinocerebellar

Question 50

Tract that is responsible for turning the head towards a stimulus

Answer 50

Spinotectal