Pediatrics Exam 1: Lecture 1

postural control

what is a critical part of motor development

limit development of other functional behaviors

delayed, immature, or abnormal development of postural systems will

- performing functional skills

- how the skills are being performed

all functions skills require some level of postural control for (2)

- understand how motor skills emerge

- understand & be able to assess quality of movement & posture

- determine age appropriateness of motor skills & how those skills are performed

- understand the multiple variables involved in the development of motor skills

- determine from this what if any interventions can & should be recommended

our job as movement specialists (5)

theories of motor control development

help HCP understand the basics of how & why motor skills change over time

- reflex-hierarchical

- cognitive

- motor learning

- dynamic systems

(4) developmental theories

nervous system or neural maturation

primary driver for reflex-hierarchical theory

- learning processes

- external influence of social scaffolding

primary driver for Cognitive theory (2)

predetermined motor programs

primary driver for motor learning theory

none

primary driver for dynamic systems

movement & motor skill

a tool to study development in all domains

- his/her world using cognition

- how to affect his/her world via adaptive skills

- how to exchange ideas via communication

- how they connect to others socially & emotionally

through observations of movement, we can infer what a young child knows about (4)

other developmental areas

new motor skills can instigate the initiation of a chain of events that lead to gain in

cephalocaudal

reflex-hierarchical theory development follows a set sequence of ____

CNS maturation

reflex-hierarchical theory is ______ driven

hierarchic maturation of neural control structures

reflex-hierarchical theory describes that development is directly related to CNS development assuming a

integration of primitive reflexes

reflex-hierarchical theory concept that reflect increasing maturity of cortical structures & emergence of higher & more complex motor skills

reflexes

involuntary responses to a specific stimuli

prenatally

reflexes can influence movements of the fetus ____

28-weeks gestation

reflexes can be present beginning at

1st birthday

most reflexes are integrated by

may not

infant reflexes (may/may not) completely disappear

maturing CNS

infant reflexes may be inhibited by

new movements

infant reflexes may be integrated into

level of neurological maturation in infants

reflexes are useful in determining

age-specific

reflexes are ___ in developing infants

tonic attitudinal reflex

persistent change in body posture

head position

what affects tonic attitudinal reflexes

- head turning to the side

- flexion of skull side extremities

- extension of face side extremities

ATNR (3)

- head flexion = UE flexion = LE extension

- head extension = UE extension = LE flexion

STNR (2)

arms follow the head

general rule to remember about STNR

optical righting reaction

orients head in space using visual input

return or "right" body to upright position

what are righting reactions of the head & trunk

adjust body parts relative to the vertical axis

how do humans use righting reactions

- automatic reactions

- enable normal standing

- maintain stability while moving

- upright head with eyes parallel to horizon

(4) examples of righting reactions

birth to 2 months

onset of righting reactions

persists throughout life

integration of righting reactions

- hold infant vertically under the arms & around the chest

- suspend them in space

- blindfold child to remove vision assist if testing for labyrinthine

test position for righting reaction

- tilt body anterior, posteriorly, & laterally from vertical by 45° or more

- allows head to drop forward, backward, & sideways

stimulus for righting reactions when testing (2)

- head orients to vertical position & is steady

- maintains proper orientation to environment

response for righting reactions when testing (2)

head lifted from prone & steady

progression of righting reactions at 4 months

head lifted from sideways & steady

progression of righting reactions between 4 & 6 months

head lifted from supine & steady

progression of righting reactions at 7 months

emergence supports development of postural control & stability

significance of righting reactions

- equilibrium reactions

- tilting reactions

balance emerges in association with organized series of (2)

- allow the whole body to adapt to slow changes in shifts on COM within the BOS

- adjust for a change in body's orientation in space to remain upright

- includes head & body righting

equilibrium reactions (3)

rotational component

what component is critical for equilibrium reactions & requires co-contraction of the trunk flexors & extensors

- response to instability in the lateral direction

- sideways stepping

staggering reactions (2)

- balance

- prevent falling

- in sitting & standing

postural reactions are necessary for (3)

- produced in response to a shift of COM caused by the moving surface

- considered an equilibrium reaction

tilting reactions (2)

- protect the body from harm after COM has been displaced beyond the BOS

- parachute reactions

protective reactions (2)

forwards

UE protective reactions development progression in sitting at 6-7 months

sides

UE protective reactions development progression in sitting at 7-8 months

backward

UE protective reactions development progression in sitting at 9 months

- movement is produced from the interaction of multiple sub-systems within the person, task, & environment

- all sub-systems spontaneously self-organize & interact in a specific way to produce the most efficient movement solution for each specific task

- development is non-linear

what does dynamic systems theory explain

wide ranges for normal skill acquisition rather than a predictable timetable

development being non-linear in dynamic systems theory

any one of the involved systems can take the lead in altering the direction of development or allow for a new level of performance

variability in dynamic systems theory

- any driving influence

- has the potential to change over time

control parameter in dynamic systems theory (2)

- neural & MSK systems

- environment

development of postural control happens through a complex interaction between (2)

body schema

an internal "representation of the body spatial properties, including length of limbs & limb segments, their arrangements, their configuration in space, & the shape of the body surface"

- interpret senses

- coordinate actions for postural control

an internal representation of body schema provides a postural frame of reference that we use to (2)

are not

steady-state & postural control (are/are not) present at birth

- lack of strength

- lack of organized motor activity

lack of head control in newborns is due to (2)

intact neuromotor system

presence of disorganized & variable movements in all planes is indicative of an

1 month

direction specific postural responses in neck muscles underlying reactive balance control in infants (neck flexors) can begin to emerge at

vision

important calibration of vestibular & proprioceptive systems, which help in developing internal models of posture

- present at birth

- need experience & learning to be maintained & refined

vision & neural programs underlying visual orientation (2)

vestibular

input that is important in the emergence of gross motor skills

visual

critical in calibrating somatosensory inputs for control of head posture

- able to hold head & upper trunk up, but unable to sit

- 4 to 5.5 months

- limiting degrees of freedom in order to gain control

stage 1 of steady-state development (3)

- able to sit independently briefly for 10-30 seconds or prop sit

- 5 to 6.5 months

- as a child gains more control, there is an increase of degrees of freedom in order to increase the adaptability of the new behavior

stage 2 of steady state development (3)

- independent sitting, but not yet crawling

- 6 to 8 months

stage 3 of steady state development (2)

- no control

- attempts to initiate upright sitting

- partial control with large range of body sway

- functional control with sway

(4) stages of mastering trunk control

sitting; sitting

reactive balance control in trunk available to limited extent in infants before ___ develops & continues to emerge after independent ___ occurs

- shaped during months prior to emergence of independent sitting

- precursor to more refined postural synergies

- reactive postural control

response synergies (3)

improved reaching abilities

improved trunk control is associated with

- trunk sways forward

- reach is jerky & takes longer to reach for toy

trunk support effect on reaching at 4 months old without pelvic support (2)

- less trunk sway

- reach is smoother & faster to reach toy

trunk support effect on reaching at 4 months old with pelvic support (2)

3

EMG analysis shows some anticipatory trunk activity at ___ months, which increases with age

before

data in study suggest that reactive balance control emerges (before/after) anticipatory control

visual

newly sitting infants rely heavily on ___ input when controlling sway

somatosensory

dependence on visual input decreases with increasing experience in independent sitting as infants begin to rely more on ____ inputs

before

infants are dependent on visual input (before/after) being able to rely on somatosensory input

- exploratory postural sway

- performatory postural sway

(2) strategies that infants combine in order to learn how to control sway when learning to stand and walk

exploratory postural sway

investigate & explore sensorimotor workspace for posture control for sensory information that will help calibrate sensory motor relationships needed for postural control

performatory postural sway

uses sensory information to control posture

- ability to support weight AG in standing position before emergence of independent stance

- not a major constraint to the emergence of postural control in infants

role of strength in transition to independent stance (2)

5

at what age do children show more steady state balance control & adaptability in balance abilities during quiet stance similar to that of adults

7 to 10

at what age are children's postural reponses basically like those in adults

15 months

at what age are compensatory postural responses of young children more variable & slower than those of adults

anticipatory activity present but highly unlikely

anticipatory postural control progression in standing in response to resistance applied when pulling a drawer at 10 to 11 months old

anticipatory activity present consistently

anticipatory postural control progression in standing in response to resistance applied when pulling a drawer at 13 months old after already started walking

able to adapt postural control to deal with the added resistance while pulling drawer

anticipatory postural control progression in standing in response to resistance applied when pulling a drawer at 15 months old

4 to 6

by ___ to ___ years of age, there should be matured anticipatory postural adjustments preceding arm movements while standing

postural control

ability to adapt sensory information about position & movement of the body in space to changing task & environmental conditions

4

development of multisensory reweighting is present at ___ years of age & contributes to a more stable & flexible control of upright stance

attentional; increasing

postural control requires ___ resources with (increasing/decreasing) postural task complexity

automation

through repetitive practice of each new development skill, neuronal maps are created & ___ occurs allowing our body to be as efficient as possible

spontaneous movement

evaluation of ____ is more accurate prediction of function

- learning through individual movement exploration through variability & errors

- tons of repetition

- intensive practice through trial & error

(3) key features of motor learning in children