Review
• Dynamical systems theory explains change in
systems that exchange energy with the
surrounding environment
• DST explains how behavior changes through
self organization
– typically no one teaches a child to run…
– speed is the catalyst
Motor Development
Re-conceptualizing Developmental
Change in Movement Patterns
Life Span Motor Development
Evolution of a Theory
& Research Program
In the beginning...a clinician!
 a knowledge of
neurodevelopmental
theory
 a fascination with
righting and
equilibrium reactions
 a love for movement
analysis
Neurodevelopmental Theory
 development is a
process of reflex
integration
Motor  lower level automatic
behavior gives way to
Ctx
Midbrain
higher level volitional
Brain stem Level
control
Spinal Level
Neurodevelopmental Theory
 Progressive
 Positive
 Add Abilities
 End State Oriented
(maturity is the end
state)
Neurodevelopmental Theory
 CNS = Cause of
Change
Biological Theory of Aging...
 Regressive
 Negative
 Loss of Abilities
 End state oriented
(end state = death)
Life Span Theory
 Development
followed by Aging
Milani - Comparetti
Milani Comparetti = my personal
Control Variable!
Change of State
Virginia... (1970s)
Wisconsin (1980s)
The Doctoral Experience
Roberton’s Component Model
Developmental Stages of Throwing
Reliability of assigning Stages
Developmental Change within
Components of Body Action
Component Model of Development
 Upper Limbs
 Axial Region
 Lower Limbs
Lawrence & Kuypers
Three descending
control systems
medial system – controls axial region
lateral system – controls proximal limb
movements
in primate studies the lateral system allowed for
differentiated arm movements
cortical system – controls distal movements
in primate studies allowed individuated finger
movments
Straying into Systems models
Not just one big hierarchy
Roberton was studying development in those
systems!
Applying Roberton’s Method
Taking it to a new task
 From Throwing to Righting
Learning the Research Process
Righting Reactions
Developed during 1st year of life
Rolling to prone
Up on hands and knees
Into sitting
Quadruped to kneeling
Kneeling to Half Kneel
Up to Stand
Righting Reactions
• Movements couple together to assume erect
stance
• Foundation for Physical Independence
Righting Reactions
First Rotational movements then
Symmetrical
But observations of young adults in PT
school revealed all were not using
symmetrical form
Studies of Righting
Rising to Standing from the Floor
Young Adults
Why Young Adults?
variability in PT students impressive
a very few showed symmetrical form when rising
Roberton examined variability to get stages of
throwing
 Lifespan perspective
 hypothesis: variation was “developmental”
Sequences
If person is in a stage he/she shows stable
behavior characteristic of that stage
If a person is moving from one stage to
another
shows variable behavior characteristic of those
two neighboring stages
Studies of Righting
Rising to Standing from the Floor
Young Adults
Variability continued to be impressive across 10 trials
Described action in each of three components of body
action
 able to identify neighboring stages for each body region
Really out on a Limb
Studies of Righting
Rising to Standing from the Floor
Children
Age differences confirmed sequences of movement
pattern development identified from adult patterns of
variation
Component Model affirmed