Flashcards in Exam 2 Study Guide 2 Deck (33):
1
stretch reflex
- monosynaptic
- muscle contraction in response to a quick stretch
2
stretch reflex aka
- myotatic
- muscle stretch reflex
- deep tendon reflex
3
cutaneous reflex
- goes along with flexion withdrawal reflex
- If you step on something sharp, you have a cutaneous reflex that causes a flexion withdrawal reflex
4
flexion withdrawal reflex
movement of a limb away from a stimulus
5
inverse myotatic reflex
AUTOGENIC INHIBITION
- agonist muscle relaxes after being stretched
- ex. stretching quads causes them to relax
6
reciprocal inhibition in a stretch reflex
- monosynaptic to agonist
- polysynaptic to antagonist
7
stretch reflex: decussation?
no
8
withdrawal reflex: poly/mono
polysynaptic
9
flexion reflex: decussation
- no decussation
- ipsilateral inhibition of extensors + contraction of flexors
10
crossed extension portion: decussation
- decussates in SC
- contralateral inhibition of flexors + contraction of extensors for WB
11
medial CST: direct connection from
cerebral cortex to SC
12
path of medial CST
motor cortex
» medullary pyramids
» SC
(descends in ventral funiculus)
13
medial CST: decussation
does not cross
- innervates ipsilateral side of LMN of trunk, neck, and shoulder
14
Which tract is the most important one controlling voluntary movements?
lateral CST
15
path of lateral CST
motor cortex (motor planning areas)
» axons through internal capsule in peduncles
» through pons/medulla
» 90% of neurons cross at pyramidal decussation
» travels to SC and synapses with LMN
16
reticulospinal tract
- begins in reticular formation
- facilitates bilateral LMNs that innervate postural and gross limb movement of muscles throughout the body
17
rubrospinal tract path
red nucleus
» decussates immediately in brainstem
» travels to cervical cord
» innervates UE (extensors of wrist/fingers)
18
corticobulbar tracts: purpose
- how we get info through cranial nerves and to the face
- motor homunculus through brainstem
19
corticobulbar tracts are important for
- expression
- swallowing
- talking
20
medial CST: synapse between UMN/LMN
cervical spinal cord
21
medial CST: decussation
no
- ipsilateral only
22
medial CST: muscles innervated
- back muscles
- shoulder
- neck
23
medial CST: function
control neck, shoulder, and trunk muscles (posture)
24
lateral CST: start/finish
start: primary motor, premotor, supplementary motor areas
finish: contralateral innervation of limbs
25
lateral CST: synapse between UMN/LMN
cervical spinal cord
26
lateral CST: decussation
some do (lower medulla), some dont
27
lateral CST: muscles innervated
- distal limbs
- fractionate movements
28
lateral CST: function
precise control of contralateral movements of limbs, fractionate movements
29
rubrospinal tract: start/finish
start: red nucleus in midbrain
finish: contralateral upper limb muscles
30
rubrospinal tract: synapse between UMN/LMN
cervical spinal cord
31
rubrospinal tract: decussation
yes, midbrain
32
rubrospinal tract: function
extends wrist and fingers
33