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Published on: August 30, 2016
Developmental shifts in the ability of infants with Down syndrome to produce treadmill steps
B D Ulrich1, D A Ulrich, D H Collier
1Department of Kinesiology, Indiana University, Bloomington.
Insights
Infants with Down syndrome can produce alternating steps on a treadmill, but later than typically developing infants. This treadmill response may offer insights into developmental delays and potential interventions.
Area of Science:
- Developmental pediatrics
- Motor control research
- Dynamic systems theory
Background:
- Infants with Down syndrome often exhibit developmental delays in motor milestones.
- Understanding the emergence of motor skills in this population is crucial for early intervention.
Purpose of the Study:
- To longitudinally assess the capacity of infants with Down syndrome to produce alternating steps on a motorized treadmill.
- To apply a dynamic systems strategy to analyze motor development in infants with Down syndrome.
Main Methods:
- Seven infants with Down syndrome (8-29 months) were studied monthly in their homes.
- Testing continued until consistent alternating step patterns were observed in three consecutive sessions.
Main Results:
- All infants eventually produced alternating steps, on average 13.3 months before independent walking.
- The onset of this treadmill response occurred at varied ages, significantly later than in nondisabled infants.
- Developmental variables influencing treadmill responsiveness differed between infants with and without Down syndrome.
Conclusions:
- Alternating treadmill stepping became more stable with age, though interlimb coordination remained variable.
- Dynamic systems theory provides a framework for understanding delayed development in this context.
- The treadmill paradigm shows potential as an intervention strategy for infants with Down syndrome.
Background And Purpose:
In this study, we used a dynamic systems strategy to examine longitudinally the ability of infants with Down syndrome to produce alternating steps when supported on a motorized treadmill.
Subjects:
Seven infants participated, ranging in age from 8 to 11 months at entry into the study and 13 to 29 months at their final session.
Methods:
Data were collected in the infants' homes on a monthly basis. Testing continued until each subject produced consistent alternating step patterns during three consecutive test sessions.
Results:
All infants responded by producing alternating steps, on average, 13.3 months before they walked independently, but they initiated this response at a wide range of chronological ages and significantly later than reported previously for nondisabled infants. Similar developmental variables (control parameters) marked the shift into responsiveness to the treadmill context for all infants with Down syndrome, but these variables differed from those identified for nondisabled infants.
Conclusion And Discussion:
With age, alternating treadmill stepping became a more stable response, although the relative timing of interlimb coordination (phase lag) of the step cycles remained quite variable across ages. We discuss our results relative to the usefulness of dynamic systems theory in understanding delayed development and the possibilities of pursuing the treadmill paradigm as an intervention approach.
