Introduction to Motor Development Flashcards
Reflex-Hierarchical Theory
- brain develops in predictable and hierarchical manner
- as brain develops we develop skills
- this was developed because of primitive reflexes.
- also dealt with milestones (ie: crawl before walk)
*RIGID THEORY OF DEVELOPMENT
How true is the is the Reflex-Hierarchical Theory?
not true brain processes develop in parallel
we now know about neural networks
Neuromaturational Models of development are responsible for developing what important concept?
Developmental Milestones
(Gesell’s theory is known as a maturational-developmental theory.)
motor milestones describe what skills change and when they change. This is useful in knowing whether a child is progressing typically.
2 types of cognitive theories
Behavioral
Piagetian
Behavioral Theory
stimulus-response approach
environment is everything -based on past experiences
positive/negative reinforcement
Aba theory is used for which population? This is based off of which theory?
Autism
Behavioral theory
- problem with this is variation, this is generalized
Piagetian Theory stages
–Sensorimotor (0-2)
–Pre-operational (2-7)
–Concrete Operational (7-11)
–Formal Operational (11+)
What did the Piagetian Theory provide us with?
Gives a framework. Some hold true some doesn’t. But what he did do is make children active participants.
They acted on their environment in order to learn. they are not passive.
Active participation is very important when it comes to development
What is motor development theories based on?
Focus is on processes involved in attaining skills
motor skills are not just reactive it is a form of problem solving (how do i get from here to toy)
skills happen in parallel - fluid and dynamic
performance is dependent on many different factors
Dynamic Systems Theory
There are many factors to consider. Development is more complex than the maturation within the CNS
• Emergence of postural control/motor skill is ascribed to complex interactions between multiple systems
What is one of the core principles of DST
Everything will move along as is, unless there is a perturbation.
ie: crawling to walking. there has to be some turbulence - maybe they want a toy
Principles of Dynamic Systems Theory (3) and what are they
• Stability and Instability
-As you get more skilled at something you will need more perturbation to change. If someone already has a habit (ie: toe walkers) you will need to work harder to break that happen. the connections are established. More stable needs more perturbation. They would need more dosing!
• Self-organization
-humans do what is most efficient. Babies self organize to figure out best way of moving. This is basses on all other systems. Maybe there is a problem.
• Interactions of countless factors over time
What happens to babies as they learn a new skill
as babies learn a new skill their old skills get worse - you need to see if this is normative or not
Principle of Turbulence. This is an important concept of DST
Why does stepping reflex ‘disappear’ only to re-emerge? What was found? (Thelen and Fisher)
It does not disappear (an reappear as walking).
She did a kinematic and EMG study.
As body mass spiked stepping in standing decreased. upright biomechanically harder. chumby babies step less than skinny babies - has nothing to do with cortical maturation. has to do with biomechanics
What is a reflex?
It is a hardwired motor program that you get for free
You are born with it.
What systems interact during development?
- Neural
- Musculoskeletal
- Respiratory • Sensory
- Organization of multiple inputs
- Internal representations for feedback control
- Anticipatory control development
- Environment
- Task
Interacting Systems in Development
- Neural
- Musculoskeletal
- Respiratory
- Sensory
- Organization of multiple inputs
- Internal representations for feedback control
- Anticipatory control development
- Environment
- Task
Example of Different Systems Involved in Development of Upright Locomotion
- Reciprocal lower extremity activity
- Development of flexor /extensor muscle activity
• Changes in size and
composition of body
- Synchronization of movement
- Visual feedback for maintaining position
- Knowing goal of task
- Motivation to move
Explain the Stepping Reflex study and its findings.
She did a kinematic and EMG study. In supine and standing.
They also did two studies one with babies in water and one with baby in supine with ankle weights. water babies stepped more and weighted babies stepped less. this proved that this was a mechanical issue and not a cortical one.
Explain the Stepping Reflex study and its findings.
She did a kinematic and EMG study. In supine and standing.
They also did two studies one with babies in water and one with baby in supine with ankle weights. water babies stepped more and weighted babies stepped less.
***This proved that this was a mechanical issue and not a cortical one. (move away from reflex hierarchical theory to DST)
Fat is very important for babies and muscle has not had time to catch up to the chubbiness
Extrinsic Factors deal with and why are they important?
Environment and task
very important to motor learning. it is different walking in a quiet room to walking outside.
What are some examples of different systems involved in developing upright walking
- Reciprocal lower extremity activity
- Development of flexor/extensor muscle activity
- Changes in size and composition of body
- Synchronization of movement
- Visual feedback for maintaining position (vestibular system)
- Knowing goal of task
- Motivation to move
Neuronal Group Selection Theory deals with
Variability is the hallmark of typical motor development
How does the DST help us with treatment?
-have to consider multiple factors
When evaluating a child we should ask:
why are they moving they way they are moving?
what is limiting the child?
what are ways we can access the system to make a change?
Neuronal Group Selection Theory
Explains the relationship of brain to behavior
-how the system solves the problem of managing movement with multiple degrees of freedom
3 basic tenets
1) Formation of primary repertoire of species-specific connections and behaviors——>how the anatomy of the brain is produced during development
2) Development of secondary repertoire based on selective activation following individual experience
- ->how experience selects for strengthening certain patterns of response from the anatomic structures
3) Primary and secondary repertoires form maps through multiple connections
- ->how the resulting maps of the brain give rise to uniquely individual behavioral functions through a process called reentry
What does this quote mean “Variability is the hallmark of typical motor development”?
Anytime you see a child or adult moving with very rigid to predictable patterns, or always choosing the same way for an end result. There is some flag that need to go up. They have obligatory strategies.
(ie: think about how many ways you get out of bed - we have a lot of different options)
Nervous System Maturation
• Importance & plasticity of the nervous system
-plasticity - the ability to change adapt and find new solutions
• Coordination of multiple levels of the nervous system for increasingly complex motor behavior and control
-it is about the complexity of networks and as we incorporate different levels we have increased complexity of motor development –> progression of skill (behavior, vestibular, etc).
• Interplay between genetics and experience
Difference between variation and variability
• Variation: presence of broad repertoire of motor function
–we all come with this because of our genetic code of being human
• Variability: capacity to select best strategy for task
–ability to select the best strategy at the moment. the one that is most efficient for you (individual)
How does one go from a broad repertoire of motor function that is species specific to an individual motor function?
Experience and trial and error
early on (infants) genetic component is important but as a baby or child develops that becomes less important because they will develop their own unique strategies
How do we get primary and secondary repertoires to link?
• Generalized movements (spontaneous movements) transitioning to intentional goal directed movements
A lot of opportunity for trial and error
When does the shift happen from primary to secondary
By 18 months of age most of this shift has happened
Primary Repertoire/Variability
• Abundant variation, with exploration of all possible solutions
–Afferent information from exploration initially not used for adaptation to environmental constraints
• Shift –afferent information used for adaptation leading to next phase
Secondary Repertoire/Variability
• Experience driven trial and error, unique to individual
–Period of selection
What happens with NGST in atypical development?
• Reduced variation –unable to experience as many strategies
–May use ‘atypical, inefficient’ strategy as this is only option!
• Reduced selection
–prolonged trial and error making their movements appear more variable
–Need much more experience to find best strategy for specific motor tas
NGST and the implications for PTs when it comes to children with atypical development
Think about it for problem solving and evaluation.
What is potentially limiting their progress (why is child only using one strategy)
- also tells you that this is the only way a child can move. Therefore is their most efficient way - if you help strengthen their systems, you can help provide more ways that are more efficient
Why is it important to use play when working with kids
It is a way to access motivation
