Infant Sitting and Multi-Directional Reaching Skill

Abstract

We tested twenty-one 6- to 10-month-old infants with a wide range of sitting experience in forward and rightward reaching during unsupported sitting on the floor. Sessions were video-recorded for further behavioral and machine learning-based kinematic analyses. All infants, including novice sitters, successfully touched and grasped toys in both directions. Infant falls, hand support, and base of support changes were rare. Infants with more sitting experience showed better upright posture than novice sitters. However, we found no differences in trunk displacement or reaching kinematics between directions or across sitting experience. Thus, multi-directional reaching is functional in both novice and experienced infant sitters. We suggest that trunk and arm stability in sagittal and frontal planes is integral to learning to sit.

Keywords:

• infancy
• postural control
• skill acquisition
• machine learning

Acknowledgments

We thank Hana Goldstone, Joel Kanneth, Nashita Karim, and Joshua Schulteis for their assistance in recruitment and data collection.

DISCLOSURE STATEMENT

The authors report there are no competing interests to declare.

DATA AVAILABILITY STATEMENT

With participants’ permission, videos from each session are shared with authorized investigators on Databrary (https://nyu.databrary.org/volume/1143). Video clips showing examples of the procedures and coding are publicly available. The coding manual, coding spreadsheets, and coding/analyses scripts are shared at https://nyu.databrary.org/volume/1143/slot/64586/-?asset=410138.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.