Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Neuro-Anatomy > Tracts > Flashcards

Tracts Flashcards

(70 cards)

Start Studying
1
Q

Each dorsal rootlet is divided into two divisions

A

lateral and medial division

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

lateral divison

A

A delta/C fibers, GSA’s, enter area of white mater @ tip of dorsal horn via lissauer’s tract, they then ascend or descent 1 or 2 cord segments, then enter grey mater and synapse

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

medial division

A

A beta/type I, II, and III; DO NOT USE LISSAUER’S TRACT, synapse in lamina III and IV, or in lower motor neuron (muscle stretch reflex: I A fiber, quick change in length of extrafusal fibers, synapse of alpha motor neuron (monosynaptic reflex)).

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

tract

A

organized bundle of axons (white mater)

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

ascending tracts

A

modulated by descending tracts by location of cell bodies**

  • arousal, affective, motivation responses of stimulus
  • unconscious monitoring/control of motor activity (posture/movement)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

first order neurons

A 
sensory neuron (A delta, A beta, type I) 
- cell bodies are always in dorsal root ganglion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

second order neurons

A

synapse in thalamus, neuron cell bodies in the thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

third order neurons

A

thalamocortical neurons

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

dorsal column/medial lemniscus (location)

A

dorsal column - ipsilateral fibers in dorsal white mater-cord
medial lemniscus - contralateral fibers in brain stem
cross @ tegmentum of caudal medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

dorsal column/medial lemniscus (information conveyed)

A

vibration, joint position, 2pt touch (and light touch), pressure (association cortex)

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

association cortex

A

the ability to feel and recognize an object in one’s hand while not looking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

dorsal column/medial lemniscus (1st order neurons)

A

1st order - in DRG

  • axons S5-T6 ascend via fasciculus gracilis
  • axons T5 - C1 ascend in the fasciculus cuneatus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

dorsal column/medial lemniscus (2nd order neurons)

A

cell bodies are in the nuclei gracile and cuneatus

- axons cross as the internal arcuate fibers and ascend as the medial lemniscus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

dorsal column/medial lemniscus (3rd order neurons)

A

cell bodies are in the VPL thalamic nucleus
- axons course through the internal capsule to the sensory cortex, postcentral gyrus/post paracentral lobule (homunculus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

dorsal column/medial lemniscus 1st 2nd and 3rd order neurons are ________ organized

A

somatotopically

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

anterolateral system conveys

A

pain and temperature (some touch and pressure)

- A delta/C fibers

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

anterolateral system - A delta fibers

A

fast conducting; localized sharp/acute pain

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

anterolateral system - C fiber

A

slow conducting; poorly localized; burning; aching pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

anterolateral system cross at

A

ventral white commissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

anterolateral system includes three tracts…

A

spinothalamic, spinoreticular, spinomesencephalic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

ALS - spinothalamic system includes…

A

neospinothalamic (somatotopically organized) and paleospinothalamic

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

ALS - spinothalamic - neospinothalmic

A

1st order - A delta
2nd order - lamina I and V (VI-VII) and axons cross and ascend
3rd order - VPL of thalamus
conveys: sharp, well localized, discriminatory pain
terminates @ primary sensory cortex (homunculus)

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

ALS - spinothalamic - paleospinothalamic

A

1st order - C fibers
2nd order - lamina VII - VIII and axons cross and ascend
- collaterals go to reticular formation
3rd order - intralaminar thalamic nucleus
conveys: dull achy pain
terminates @ widespread cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

ALS - spinoreticular tract conveys

A
  • dull achy
  • autonomic, behavioral, and emotional responses to the painful stimuli
  • arouses cortex to maintain alertness and attentiveness (focus attention on a painful area)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
ALS - spinoreticular tract neurons
1st - afferent from cutaneous receptors 2nd - contralateral to pontine and medullary reticular formation and ipsilateral to medullary reticular formation 3rd - thalamic nuclei, then cortex via anterior cingulate/insular cortices
26
ALS - spinomesencephalic tract conveys
reflex responses
27
ALS - spinomesencephalic tract neurons
1st - synapse in grey mater 2nd - cross in ventral white commissure, then synapse @ super colliculus for reflex response or synapse @ periaqueductal grey - PAG: descending feedback to dorsal horn; synapse in reticular formation to modulate pain
28
ALS - spinothalamic - neospinothalamic vs. ALS - spinothalamic - reticular/mesencephalic/hypothalamic
neospinothalamic: seriousness of the pain (posterior partietal lobe, insula of amgdala, anterior cingulate cortex: prefrontal cortex) reticular/mesencephalic/hypothalamic: pain is uncomfortable (brainstem nuclei, thalamus, hypothalamus)
29
anterior cingulate cortex (ACC)
function: emotional component of pain
30
ACC: amygdala
memory
31
ACC: insula
autonomic component
32
ACC: parietal cortex
post central sensory
33
ACC: prefrontal cortex
motor
34
nucleus raphe magnus
part of reticular formation; raphe spinal tract then descends from there
35
dorsal spinocerebellar tract conveys
unconscious proprioception from the trunk and lower extremities (some touch and pressure)
36
dorsal spinocerebellar tract neurons
1st - cell bodies in DRG 2nd - cell bodies in clarke's nucleus (lamina VII) cord segments C8/T1-L3; axons climb ALL THE WAY UP - exit @ inferior cerebellar peduncle to terminate in cerbello cortex
37
dorsal spinocerebellar tract neurons (L4-S3)
axons travel up to clarke's nucleus and synapse there
38
ventral spinocerebellar tract conveys
unconscious proprioception from the trunk and lower extremities; transmits information from locomotor areas; may monitor activity of descending tracts
39
ventral spinocerebellar tract neurons
1st - sensory fibers and from interneuronal motor pools 2nd - cell bodies in the ventral horn - axons cross and ascend as the VSCT and leave @ superior cerebellar peduncle, then recross in the cerebellum before terminating in the cerebellar cortex
40
DSCT axons leave @ ________, VSCT axons leave @ ________ then recross, CuCT axons leave @ _________ inferior cerebellar peduncle, and Spino-Olivary tract axons leave @ ________
DSCT - inferior cerebellar peduncle VSCT - superior cerebellar peduncle CuCT - inferior cerebellar peduncle Spino-Olivary - inferior cerebellar peduncle
41
cuneocerebellar tract conveys
unconscious proprioception from the upper extremities
42
cuneocerebellar tract neurons
1st - cell bodies in DRG (ascend through fasciculus cuneatus) 2nd - cell bodies in the lateral/accessory cuneatus nucleus - axons ascend as the CuCT and leave @ brain stem via inferior cerebellar peduncle to terminate in the cerebellar cortex
43
spino-olivary tract conveys
unconscious proprioception that ultimately terminated in the cerebellum; works with cerebellum in motor learning and making corrections during on-going movements
44
spino-olivary tract neurons
1st - axons terminate @ dorsal horn 2nd - axons cross and ascend to the inferior olivary nucleus and synapse; axons from here cross and travel via the inferior cerebellar peduncle into the cerebellum
45
somatic motor pathways
- direct pathway from cerebral cortex to spinal cord and out to muscles - indirect pathway includes synapses in basal ganglia, thalamus, reticular formation and cerebellum
46
corticospinal tract conveys
- provides skill, precision, fractionation, speed, and agility during voluntary movements - feedback to sensory relay areas (dorsal horn, gracile/cuneate nuclei)
47
only descending tract in the pyramids; originates in the motor (precentral gyrus), premotor, supplementary motor cortices, postcentral gyrus, paracentral lobule
corticospinal tract
48
primary motor cortex axons descending pathway
corona radiata, internal capsule, crus cerebri, basilar pons, and pyramids - somatotopically organized
49
primary motor cortex axons before they cross pyramidal decussation become
lateral corticospinal tract (LCT) or ventral corticospinal tract (VCT) - VCT does not cross at pyramidal decussation, but instead at ventral white commissure
50
reticulospinal tracts:
pontine ReSPT and Medullary ReSPT
51
pontine ReSPT conveys
motor neurons to axial and limb extensor muscles (descends ipsi)
52
medullary ReSPT conveys
inhibit/excite motor neurons to cervical muscles and excites motor neurons to back muscles (descends bilateral)
53
reticular formation receives input from:
motor cortex, cerebellum, and brain stem nuclei
54
reticular formation conveys
control and coordinate automatic movements by modulating activity in cord locomotor pattern generators - position of body parts during movements - stabilization of proximal limb joints so voluntary movements of distal limbs can occur
55
vestibulospinal tracts:
lateral VeSpTr and medial VeSpTr
56
lateral VeSpTr conveys
effects antigravity muscles | - maintains balance and upright posture
57
lateral VeSpTr nucleus and terminates
lateral vestibular nucleus and terminates ipsi in ventral horn
58
medial VeSpTr conveys
maintains head position in response to vestibular stimuli
59
medial VeSpTr nucleus and travels
medial vestibular nucleus and descends bilaterally within MLF - synapses ONLY in cervical cord segments
60
tectospinal tract conveys
reflex head movements in response to visual, auditory, cutaneous stimuli - head movements for tracking a moving stimuli
61
tectospinal tract path
- originates @ superior colliculus of midbrain - crosses in the dorsal tegmental decussation - terminates in cervical cord segments
62
rubrospinal tract conveys
facilitates flexor and inhibits extensor motor neurons | - receives input form cerebellum and motor cortex
63
rubrospinal tract path
- originates @ red nucleus of midbrain - crosses at ventral tegmental decussation - extends to cervical cord in humans; length of cord in lower mammals
64
descending autonomic fibers path
- originate @ hypothalamus and brain stem nuclei | - terminate @ preganglionic neurons
65
aminergic pathways (raphespinal)
- originate in reticular formation | - terminate in dorsal horn
66
solitariospinal tract path
- originate @ nucleus of the tractus solitarius and medullary reticular formation - terminate @ phrenic motor nucleus and motor neurons to intercostal muscles
67
lower motor neurons lesion signs
fasciculations (muscle contractions), neurogenic atrophy, A or hyporeflexia, flaccid paralysis
68
upper motor neuron lesion signs
spasticity or hypertonicity, hyper-reflexia, decreased/absent superficial reflexes, pathological reflexes (babinski)
69
lower motor neurons
alpha/gamma fibers
70
upper motor neurons
descending tracks | - captain = corticospinal tract

Neuro-Anatomy (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions