Lecture 4: Middle- Late Infancy Flashcards
What is the definition of postural control systems?
automatic reactions that provide the background for postural adjustments necessary to perform a variety of skilled motor activities
Wha is postural control?
controlling the body’s position in space for purposes of stability and orientation
What are the two dimensions of postural control?
COM within BOS, alignment of body segments
What months do righting and equilibrium reactions onset?
4-6 months
What systems are involved in postural control?
CNS, MS, Sensory, cognitive
How is an infants sensory organization different than an adult?
infants use vision mostly
adults use somatosensation and vestibular
What are the four types of postural control?
- static
- reactive
- anticipatory
- adaptive
What is static postural control?
controlling postural sway with ankle strategy
maintaining COM within BOS
What is reactive postural control?
reaction to unexpected perturbations
response dependent on speed, direction and force
What is anticipatory postural control?
made before a movement, requires fee forward process
What is adaptive postural control?
modification of motor response due to change in environment or task
influenced by cognition, perception, attention and intention
What are righting reactions?
initiates movement toward alignment/vertical
ex: labyrinthine, optical, BOH/NOB, Landau
What are equilibrium reactions?
keeps COM within BOS, more refined and rotational
ex: tilting, postural fixation, protective extension
What is a landau reaction?
when suspended in prone the infant will extend spine and head to feet in that order
How is rolling in middle infancy different than with young infants?
middle infants begin to add rotation when going into sidling rather than log rolling
What is protective extension reactions?
if you are holding a baby in prone then lower them towards a surface they will extend head and arms to protect themselves
What is visual placing?
flexion then extension when landing
What is positive supporting right reaction?
extension of extremities when touching surface and supported
ex. held while standing on a surface
When is the onset of tilting reactions?
around 6 months
occurs when base is moving
outcome: concavity on the upward side or lateral flexion
When is the onset of postural fixation?
occurs slight later but still middle infancy when base is stable but experience a perturbation
What are implications if these righting/ postural reactions are not developed?
infant will experience unrefined motor movements
What are general motor trends of middle infants?
- increased midline orientation
- AG control in prone and supine
- sitting begins
What are changes in CNS of middle infant?
first big growth of CNS, doubles in size
weighs half of adult brain
malnutrition can lead to lack of glial cell development due to lack of vascularity in CNS
What are skills of middle infant in prone at 4 months?
prone on elbows with chest off
pivot prone
