CN- Muscle Spindle & GTO and Reflex Arc

sense change in muscle length

muscle spindle

sense change in muscle tension/force

GTO

___ ____ is in parallel to extrafusal muscle fibers

muscle spindle

___ is in series with extrafusal muscle fibers

GTO

what does the muscle spindle consist of

nuclear bag, nuclear chain

smaller diameter and nuclei are more spread out

nuclear chain

large diameter with clustered more central nuclei

nuclear bag

arise from dynamic nuclear bag fibers

1a phasics

arise from nuclear chain fibers

1a tonics

sense both the rate of muscle lengthening and muscle length changes

1a phasics

sense muscle length changes

arise from GTOS and are in series with the extrafusal muscle fibers

1b afferents

what is the basis/mechanism for cross fiber massage at the musculotendinous junction

GTO

what are at the polar ends of the muscle spindle (static and chain)

flower spray receptors

what type of neuron comes from the flower sprays

II afferent

what does the II afferents do

crossed extension reflex and crude walking

DTR or Phasic Reflexes: Phase 1

stretching stimulates sensory receptor

DTR or Phasic Reflexes: Phase 2

sensory neuron excited

DTR or Phasic Reflexes: Phase 3

sensory neuron activates motor neuron

DTR or Phasic Reflexes: Phase 4

motor neuron excited

DTR or Phasic Reflexes: Phase 5

effector contracts and relieves stretching

uncrontrolled or uninhibited reflex arc activity

hypertonic

what is likely damaged with a hypertonic patient

inhibitory motor tracts

under facility reflex arc activity

hypotonic

what is likely damaged with a hypotonic patient

facilitory dececending motor tracts

what is responsible for clonus

sustained monosynaptic reflex arc

can be a result of a LMN or UMN injury

hypotonicity

is always indicative of an UMN lesion

hypertonicity

tonic reflexes are normally assessed by what

modified ashworth scale

Modified Ashworth Scale: what is "typical"

0

Modified Ashworth Scale: as the numbers increase what does that correlate with

increased tone/ resistance to passive stretch

does the Modified Ashworth Scale have any grades for hypotonicity

no