DPT 7120

motor control

neural, physical, and behavioral aspects of movement

how the CNS produces purposeful, coordinated movements in its interaction with the rest of the body and environment

physical and physiological processes that make movement possible, regulate movement, and organize functional movements

neural aspect of movement

ascending/afferent input

descending/efferent output

physical aspect of movement

movement patterns and strategies

behavior aspect of movement

internal and external behavioral influences

motor learning

process of motor skill acquisition through practice, exposure, and experience

sustained change in motor behavior

what mechanisms are involved in motor learning?

use

instruction

reinforcement

sensorimotor adaptation

motor development

ongoing process of change in movement and motor planning

motor control theories (can work in tandem)

hierarchical

motor program

dynamic systems

hierarchical model

top down — higher nervous system centers control or inhibit activity below

levels within hierarchical model

cortex → midbrain → brainstem (and spinal cord)

role of cortex in hierarchical model

highest level of control; controls equilibrium actions

volitional movement and higher-level coordinated activities

role of midbrain in hierarchical model

controls righting reactions

role of brainstem and spinal cord in hierarchical model

controls primitive reflexes

how does damage to CNS present under hierarchical model?

regression from cortical level control to brainstem level control

return of primitive reflexes below level of injury

motor program model

information processing approach

skill acquisition occurs based on stimulus and response interaction

basic pathway of motor program model

afferent sensory information enters → brain processes → efferent motor output occurs

requirements for recalculation in motor programming model

awareness, processing, and changes to motor output

how can the process of recalculation be impacted in development?

developmental delay → cognitive delay

changes degree of cognitive processing in recalculation

closed loop feedback control in motor program model

awareness, perception, sensation of output fed back into system as input to make necessary modifications

modes of skill acquisition in closed loop feedback control

practice

slow, accurate movement

trial and error

types of extrinsic feedback in motor program model

tactile

auditory

visual

verbal

types of intrinsic feedback in motor program model

proprioception

light touch

kinesthetic awareness

vestibular

schema

foundational requirements for all possible elements in a movement

open loop feedback control motor program model — schema theory

abstract memory representation within the brain creates automatic movement pattern that does not require feedback

necessary components of “muscle memory” — schema theory

memory trace

perception trace

progression of motor programming model/skill acquisition

closed loop → open loop

memory trace — schema theory

initiates movement

perceptional trace — schema theory

guides body through remembered, automatic movement pattern

generalized motor program (GMP)

memory structure that provides instruction for control of similar actions

develops through practice

provides basis for generating and sequencing movements within class of movements that share similar invariant features

modifiable and generalizable factors of GMP

overall force

overall duration

mm. used

unmodifiable factors of GMP

sequence

relative timing

relative force

retention of movement

ability to perform movement over time

transfer of learning

ability to use learned movement in new situation

dynamic systems model

multiple variables establish the context for movement

components of dynamic systems model

individual

task

environment

aspects of individual in dynamic systems model

shape and size of body

psychological state

behavior

aspects of task component in dynamic systems model

goal

speed

accuracy

equipment

challenge level

aspects of environment in dynamic systems model

temperature

gravity

surface

distraction

goals of dynamic systems model

generalizability of skill

seamless transference of skills from one environment/task to another

safely navigating similar task in new environment and new tasks in similar environment

flexibility and confidence to progress to new task in new environment

primitive reflex

involuntary response to specific external stimulus

3 Goals of primitive reflexes

protection

nutrition

survival

postural reactions (5)

positive support

labyrinthine righting (lateral head)

neonatal neck on body (NOB)

optical righting

Landau

locomotor infantile reflexes

stepping

crawling

swimming

protective infantile reflexes

flexor withdrawal response

Moro reflex

startle reflex

TLR

placing reflex

nutritive infantile reflexes

rooting reflex

sucking reflex (sometimes non-nutritive)

ATNR

asymmetrical tonic neck reflex

TLR

tonic labyrinthine reflex

reflexes/reactions developed in later infancy/early childhood that remain permanent

righting reactions

balance reactions

protective reactions

righting reactions

keeping one’s head in line with the body

balance reactions

keeping oneself from falling over when balance is lost

protective reactions

putting arms or legs out to prevent injury during a fall

how might delayed development of righting, balance, and protective reactions affect typical motor development of an infant?

may result in delayed (OR ABSENT) acts of sitting, standing, and walking due to inability for child to maintain balance in response to changes in COG

palmar grasping reflex testing (~4 months)

apply pressure to palm of hand OR hyperextend wrist

RESPONSE: flexion of fingers

plantar grasping reflex testing (~10 months)

apply pressure to sole of foot

RESPONSE: flexion of toes

Moro reflex testing (~6 months)

change head position; drop backward in a sitting position

RESPONSE: arms and legs extend, fingers spread, then arms and legs flex

suck/swallow reflex testing (~4 months)

touch face above or below lips

RESPONSE: sucking motion followed by swallowing motion

rooting reflex testing (~4 months)

touch cheek close to lips

RESPONSE: rotates head toward stim.

Babinski reflex testing (0-12 months)

strongly stoke sole of foot from heel to toes

RESPONSE: toes extend

stepping reflex testing (~2 months OR incr. wt)

support infant upright and gently place feet on flat surface

RESPONSE: walking pattern in legs

(can generalize to crawling/swimming)

asymmetrical tonic neck reflex testing (~4 months)

turn or laterally flex the head

RESPONSE: increased extension on chin side, w/flexion of limbs on head side

symmetrical tonic neck reflex testing (4-10 months)

flex or extend head and neck

RESPONSE: flexion — flexion of UEs, ext. of LEs; extension — extension of UEs, flexion of LEs

tonic labyrinthine reflex testing (~6 months)

stimulate vestibular apparatus by tilting or changing head position

RESPONSE: flex head = flex in limbs; supine — ext. in limbs

positive support reflex testing (~2 months)

touch balls of feet to a firm surface in an upright position

RESPONSE: ext. LEs to support wt. in standing

primitive reflex profile

5 point scale (0-4) to quantify PRIMITIVE reflex responses

0 = absent

1 = small change in tone

2 = physically present and visible

3 = noticeable strength and force

4 = strong

Galant reflex testing (~2 months)

scratch skin of infant’s back from shoulder downwards ~1in lateral to spinous processes

RESPONSE: incurvation of trunk, with concavity on stimulated side

crossed extensor reflex testing (4-6 months)

apply noxious stimulus to sole of foot

RESPONSE: ext. of other LE with adduction and IR into talipes equinus

flexor withdrawal reflex testing (doesn’t integrate)

apply noxious stimulus to sole of foot

RESPONSE: withdrawal of foot (LE flex)

startle reflex testing (~6 months)

provide noxious sound or light

RESPONSE: arms and legs extend, fingers spread, then arms and legs flex

placing reflex testing (~2 months)

press dorsum of hand or foot at table edge

RESPONSE: arm or leg will flex to clear edge

persistence of Babinksi reflex impedes:

standing, walking, balance

persistence of flexor withdrawal reflex impedes:

walking

persistence of crossed extension reflex impedes:

reciprocal LE mvmt; scissoring gait

persistence of Galant reflex impedes:

midline awareness, scoliosis

persistence of Moro reflex impedes:

calm state

persistence of positive support reflex impedes:

walking

persistence of of stepping reflex impedes:

walking

persistence of rooting reflex impedes:

rolling, speech, oral motor control

persistence of sucking reflex impedes:

swallowing (choking), speech

persistence of startle reflex results in:

lack of chronic habituation, chronic overreaction and fight/flight

persistence of tonic labyrinthine reflex impedes:

creeping, standing, sitting

persistence of ATNR impedes:

midline, feeding

persistence of STNR impedes:

quadruped, creeping

persistence of placing reflex impedes:

volitional mvmt

persistence of palmar grasp reflex impedes:

hand function

persistence of plantar grasp reflex impedes:

standing, walking, balance

atypical primitive reflex responses

persistence

absence

significantly weak

excessively strong

asymmetrical (if symmetry expected)

labyrinthine right (lateral head)

vestibular component for maintaining/restoring alignment

optical righting

visual input to orient head

neck on body righting

maintain or restore alignment of body segments in relation to each other (log roll w/no dissociation)

Landau reaction

prone suspension = head/limb ext

Order of postural reactions to restore balance when displaced

righting

equilibrium

protective

equilibrium reactions

whole body response dependent upon multiple stimulus sources; requires higher functioning

lateral sitting equilibrium reaction

head and trunk right →

arm and leg abduct opposite wt. shift →

head and trunk rotation toward abducted extremities

equilibrium reaction progression

prone @ 6 months

supine & sitting @ 7-8 months

quadruped @ 9-12 months

standing @ 12-24 months

types of protective reactions

parachute response

stepping or staggering response (lean and let go)

parachute response testing

quick displacement of COG outside BOS

RESPONSE: UE protective extension

(sitting @ 6-7 mo, sideways @ 7-8 mo, backward @ 9-10 mo)

role of sensation in newborns

cue reflexive movements

role of sensation in childhood and later

guides volitional mvmts and postural reactions

progression of mobility-stability relationship

1. uncontrolled mobility

2. Stability develops

3. Volitional, skilled mobility develops (attention driven)

sensory systems

tactile

vestibular

olfactory

auditory

visual

gustatory

proprioception