Motor Development - Chapter 4

spontaneous movements

not caused by known external stimuli

reflexive movements

stereotypical responses elicited by specific external stimuli

spontaneous movement examples

• arm movements (resembles reaching)

• kicking movements (resembles walking)

categories of infantile reflexes

primitive, postural, locomotion

primitive reflexes

present from birth

• reflexes tend to lose strength gradually and disappear around 4 months

postural reflexes

automatically help the infant maintain posture; appears around 2 months

• keeps the head upright to maintain breathing

• helps to roll over

• helps to attain standing position

locomotor reflexes

swimming, stepping, crawling

• appears much earlier then and disappears before corresponding voluntary movements

philosophies of reflexes

structural, functional, applied

structural reflex philosophy

reflexes exist as a byproduct of the human neurological system

functional reflex philosophy

reflexes exist to help infant survive

applied reflex philosophy

reflexes prepare infants for future movements

asymmetrical tonic reflex

start: supine

stimulus: turn head to one side

response: same-side arm and leg extend

palmar grasp reflex

stimulus: touch baby’s palm

response: hand closes tightly

symmetrical tonic neck reflex

start: supported sitting up position

stimulus: extend/flex head and neck

response: arms extend and legs flex, OR arms flex and legs extend

moro reflex

start: supine position

stimulus: shake head (ex. by tapping pillow)

response: arms, legs, fingers extend; then arms and legs flex

labyrinthine righting reflex

start: supported upright

stimulus: tilt infant

response: head moves to stay upright

stepping reflex

stimulus: place soles of feet on flat surface

response: legs move in walking pattern

dertotative righting

start: supine position

stimulus: turn head to one side OR turn body and legs to one side

response: body turns to align with head; head turns to align with body

parachute reflex

start: held upright

stimulus: lower infant toward ground rapidly

response: legs & arms extend

rate limiter

individual constraints that inhibit or slow attainment of a motor skill