The Effects of Different Exteroceptive Experiences on the Early Motor Repertoire in Infants With Down Syndrome.

Objective: Down syndrome is a chromosomal abnormality in which muscle tone, motor development, and sensory systems are affected. The objectives of this study were to examine the changes in movements and postures of 3- to 5-month-old infants with Down syndrome and infants who were neurotypical controls during exposure to a rough-textured surface and to compare the differences occurring before and during an exteroceptive condition that was different between the 2 groups.

Methods: In this quasi-experimental study, participants were 20 infants with Down syndrome (8 female infants; age range = 10-18 weeks, mean [SD] = 12 weeks 2 days [2 weeks 2 days]) and 20 age-matched infants with typical development (8 female infants; age range = 9-17 weeks, mean (SD) = 12 weeks 6 days [1 week 5 days]). The movements and postures of the infants, including fidgety movements, were assessed according to the General Movements Assessment, which determines the Motor Optimality Score (MOS), on 2 surfaces.

Results: The MOS outcomes of the infants with Down syndrome (median = 21.5, range = 6-28) were significantly lower than those of the infants who were neurotypical (median = 28, range = 23-28) on a standard mattress. The postures were found to be significantly better in infants with Down syndrome during exposure to a rough-textured surface. The MOS did not change due to the different exteroceptive experiences in infants with Down syndrome and infants who were neurotypical.

Conclusion: The different exteroceptive experiences caused only postural alterations, which might play a crucial role in early intervention programs for infants with Down syndrome.

Impact: This is the first study, to our knowledge, on the effects of different exteroceptive conditions, such as a coco coir mattress covered with muslin fabric, on the early motor repertoire in infants with Down syndrome. The findings showed that infants with Down syndrome had heterogeneity in their fidgety movements and large variability of the MOS, and the MOS results from infants with Down syndrome were lower than those of infants who were neurotypical. Fidgety movements and the MOS did not change due to the different exteroceptive experiences in either group. Significant improvements in posture were observed during exposure to a rough-textured surface. The improvement of posture is essential; clinicians might consider the positive effect of putting an infant with Down syndrome on a rough-textured surface and include this strategy in early intervention programs.