Development of postural control

Question 1

Why is emergence of postural skills important?

Answer 1

Requires development of postural activity to support the primary movement

Question 2

What happens if postural system is immature or its development is delayed?

Answer 2

Immature: is limiting factor on emergence of other behaviors and inhibition of reflexes
Delayed/abnormal development: constrain child’s ability to develop independence in mobility and manipulatory skills

Question 3

T/F: reflexes are predictive movements in response to a stimuli?

Answer 3

True

Question 4

What does integration of reflexes allow?

Answer 4

All reflexes should be gone by 9-12 months.
Integration follows a sequence that correlates with the acquisition of motor skills.
If reflexes persist beyond time of anticipated decline, it may signal brain abnormalities

Question 5

What are problems associated with retention of primitive reflexes?

Answer 5

CP, TBI, genetic syndromes

Question 6

What is the new model of postural development

Answer 6

involves more than maturation of reflexes within CNS.

Emergence is due to complex interaction between neural and musculoskeletal systems

Question 7

What are postural reactions?

Answer 7

Automatic responses to sensory input that act to keep body parts in alignment, maintain equilibrium, and prevent injury.
Important for static and dynamic balance
Appear between 2-18 months, and persist throughout life

Question 8

What are the 3 types of postural reactions?

Answer 8

Righting (vertical and rotational)
Equilibrium (tilting, postural fixation)
Protective

Question 9

What are righting reactions?

Answer 9

Orientation of head to vertical OR body parts are restored to normal alignment following rotation

Question 10

What are types of vertical righting?

Answer 10

Optical: tip body any direction-> head rights to vertical
Labrynthine: occlude vision and tip body any direction-> head rights to vertical

Question 11

What are types of rotational righting?

Answer 11

Neck righting on body: turn head to one side-> body log rolls
Body righting on body: rotate one body segment-> body rolls segmentally
BROB is considered mature response and NROB is usually not seen after 12 months

Question 12

When is onset of vertical and rotational righting?

Answer 12

Vertical: birth to 2 months
Rotational: 4-6 months

Question 13

What are protective reactions?

Answer 13

extension of limbs when balance is challenged

Question 14

What are the 4 types of protective reactions and their time of onset?

Answer 14

Downward: onset 4 months
Forward: onset 6-7 months
Sideways: onset 7 months in sitting
Backward: onset 9-10 months in sitting

Question 15

What are definitions of the 4 protective reactions?

Answer 15

Downward: child thrust feet first toward surface-> extension/abduction of legs
Forward: child thrust head first toward surface-> extension/abduction of arms
Sideways: child pushed gently to either side in sitting-> protective extension of one arm in direction of force
Backward: child pushed backwards-> protective extension of both arms backward

Question 16

What are equilibrium reactions?

Answer 16

Total body responses

Question 17

What are the two types of equilibrium reactions?

Answer 17

Tilting reactions: movements on unstable BOS- support surface moves under the body
Postural fixation: movements on stable BOS- body moves over support surface

Question 18

What are the 3 types of tilting reactions and when is their onset?

Answer 18

Prone (6 months): child is tilted laterally-> spinal concavity and ext/abd of limbs on elevated side; rotation of head and upper trunk toward midline and protective extension on downward side may occur
Supine (7-8 months)
Sitting (7-8 months)

Question 19

What is onset of the postural fixations?

Answer 19

Quadruped: 9-12 months
Standing: 12-21 months

Question 20

What are two types of motor systems?

Answer 20

Reactive postural adjustments (RPAs): appropriate muscle response to perturbation
Anticipatory postural adjustments (APAs): cognitive process for predicting postural requirements and selecting timely anticipatory motor strategies

Question 21

T/F: APAs and RPAs emerge in parallel during development?

Answer 21

True

Question 22

When are APAs learned?

Answer 22

Learned with voluntary movements to sit, crawl, and walk

Question 23

What are characteristics of immature movements patterns (neurological problems)?

Answer 23

inconsistency, preseveration, mirroring, asymmetry, loss of dynamic balance, falling after performance, extraneous movements, inability to maintain rhythm or pattern, inability to control force, inappropriate motor planning

Question 24

A delay in motor development occurs if…

Answer 24

Primitive reflexes do NOT appear in first year of life.
Primitive reflexes appear, but DO NOT disappear by the end of the first year.
Equilibrium reactions do not appear by the end of the first year.
Equilibrium reactions do not persist throughout life.

Question 25

What sensory systems play a part in postural reactions?

Answer 25

visual, vestibular, somatosensory

These 3 systems work together and can compensate for each other

Question 26

What input do the 3 sensory systems receive?

Answer 26

Vision: feedback (closed loop) correction and feedforward (open loop or anticipatory) control
Somatosensory: body positioning and righting
Vestibular: regulates head control and references gravitational forces

Question 27

When are vision postural responses seen in a child?

Answer 27

Responses of the head are seen as early as 3 post natal days in supported sitting.
Sway in response to looming visual stimulus in independent sitting is seen at 11-16 months
Responses to looming visual stimulus in supported stance are seen as early as 5 months
New walkers (13-17 months) sway excessively and are apt to fall in response to a looming visual stimulus in standing. Sway decreases as child gets more experience.

Question 28

When do vestibular and somatosensory reactions emerge?

Answer 28

Reactive, directional muscle responses emerge at age 4-5 months in sitting (trunk), age 7-9 months in standing (ankle)
Ability to maintain standing after perturbation occurs at 14-15 months

Question 29

How can development of postural control be characterized?

Answer 29

continuous development of multiple sensory and motor systems, which manifest behaviorally in a discontinuous step-like progression of motor milestones