Related Experiment Video
Updated: Oct 27, 2025
Quantifying Learning in Young Infants: Tracking Leg Actions During a Discovery-learning Task
Published on: June 1, 2015
Multiple patterns of infant rolling in limb coordination and ground contact pressure
Yoshio Kobayashi1,2, Arito Yozu3, Hama Watanabe1
1Graduate School of Education, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Insights
Infants use diverse strategies to roll over, coordinating body segments and ground interactions. Their unique movement patterns differ from adults, reflecting individual biomechanical constraints.
Area of Science:
- Developmental motor control
- Biomechanics
- Infant motor development
Background:
- Infant rolling involves complex coordination of multiple body segments.
- Previous research focused on kinematics, with limited understanding of kinetics during infant rolling.
- Understanding the forces and pressures involved in infant rolling is crucial for developmental studies.
Purpose of the Study:
- To investigate the kinetic characteristics of body segments during infant rolling.
- To analyze ground contact pressures and movement patterns in infants aged 9-10 months.
- To compare infant rolling strategies with those observed in adults.
Main Methods:
- Utilized a pressure mat to measure ground contact pressure under various body segments.
- Employed a three-dimensional motion capture system to track body segment displacements.
- Analyzed data from 17 infants aged 9-10 months.
Main Results:
- Infants exhibited 2-4 distinct rolling movement patterns, including axial rolling, spinal flexion, and shoulder girdle leading.
- Arms and legs showed minimal pressure contribution in axial rolling and spinal flexion.
- The contralateral leg exerted significant push-off pressure before rolling in shoulder girdle leading patterns.
- Few infant rolling patterns matched adult movement strategies.
Conclusions:
- Infants employ varied strategies to coordinate body segments and interact with the ground during rolling.
- Infant rolling patterns are unique and influenced by their specific biomechanical constraints.
- Developmental differences in motor patterns highlight the adaptive nature of infant movement acquisition.
Abstract:
Infants acquire the ability to roll over from the supine to the prone position, which requires body coordination of multiple degrees of freedom under dynamic interactions with the ground. Although previous studies on infant rolling observed kinematic characteristics, little is known about the kinetic characteristics of body segments in contact with the surface. We measured the ground contact pressure under the arms, legs, head, and proximal body segments using a pressure mat and their displacements using a three-dimensional motion capture system. The data obtained from 17 infants aged 9-10 months indicated that most of them showed 2-4 of 6 highly observed movement patterns, including 1 axial rolling, 2 spinal flexion, and 3 shoulder girdle leading patterns. The arms and legs had small contributions to the ground contact pressure in the axial rolling and spinal flexion patterns. The ipsilateral leg in relation to the rolling direction was involved in supporting the body weight in only 1 shoulder girdle leading pattern. The contralateral leg showed large peak pressure to push on the floor before rolling in 3 shoulder girdle leading patterns. The results indicate that infants can produce multiple rolling-over patterns with different strategies to coordinate their body segments and interact with the floor. The results of the analysis of the movement patterns further suggest that few patterns correspond to those reported in adults. This implies that infants generate unique motor patterns by taking into account their own biomechanical constraints.
Related Concept Videos
01:14Rolling With Slipping
An object's rolling motion is characterized by its rotation around its axis, while linear motion refers to the object's translational motion along a surface. Frictional forces can...
01:21Rolling Resistance
For instance, imagine a hard cylinder rolling on a comparatively soft surface. The cylinder's weight compresses the surface beneath it. As the cylinder moves, the material in front of it slows down...
01:09Rolling Without Slipping
01:07Development of the Limb Synovial Joints
The mesenchymal stem cells differentiate into chondrocytes that form the hyaline cartilage, and later the cartilaginous model of the bone. This model further transforms into a bone. This process is known as endochondral ossification.
During development, the limbs...
01:22Somatic Spinal Reflexes
One of the most well-known somatic spinal reflexes is the stretch reflex, which is activated by the sudden stretching of a muscle. This reflex involves the activation of specialized sensory receptors called muscle spindles, which are located in the muscle tissue and detect changes in the length and speed of muscle contractions. When a muscle is suddenly...