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Quantifying Learning in Young Infants: Tracking Leg Actions During a Discovery-learning Task
Published on: June 1, 2015
Asymmetrical motor behaviour as a window to early leg preference: a longitudinal study in infants 7-12 months of age
1a Department of Physical Therapy, Faculty of Social Welfare and Health Sciences , University of Haifa , Haifa , Israel.
Insights
Infants show consistent leg preference when pulling to stand from a half-kneel position. This preference strongly correlates with leg use in asymmetrical four-point patterns, indicating functional lower limb asymmetry in early development.
Area of Science:
- Developmental motor control
- Infant biomechanics
- Neurodevelopmental studies
Background:
- Leg preference, or limb asymmetry, is observable in various infant motor tasks.
- Understanding early leg preference is crucial for tracking typical motor development and identifying potential deviations.
- The half-kneel pull-to-stand (PTS) offers a unique task to observe asymmetrical leg use in a controlled, bilateral context.
Purpose of the Study:
- To investigate leg preference in infants during the half-kneel pulling-to-stand (PTS) task.
- To examine the relationship between leg preference in half-kneel PTS and asymmetrical four-point patterns.
- To document functional asymmetry in infant lower limbs during specific motor tasks.
Main Methods:
- Longitudinal observation of 27 infants from 7-12 months of age in their homes.
- Leg preference determined by the "lead-out" limb during half-kneel PTS.
- Complementary assessment of leg preference in asymmetrical four-point patterns for infants who developed them.
Main Results:
- Infants demonstrated a consistent leg preference during the half-kneel PTS task throughout the study period.
- A strong correlation was observed between leg preferences in half-kneel PTS and asymmetrical four-point patterns.
- The study documented significant functional asymmetry in infant lower limb usage.
Conclusions:
- The half-kneel PTS task is a valid method for assessing leg preference in infants.
- Leg preference in half-kneel PTS is linked to other asymmetrical motor behaviors, suggesting a generalized functional asymmetry.
- The choice of motor task significantly influences the documentation of leg preference and functional asymmetry in infants.
Abstract:
This longitudinal study explored leg preference in infancy during half-kneel pulling-to-stand (PTS) and asymmetrical four-point kneeling, which is part of the typical motor repertoire of infants. The special characteristics of the half-kneel PTS as a discrete task, performed in a bilateral context provide the opportunity to explore leg preference during an asymmetrical behaviour. Twenty-seven infants were observed in their homes, every 3 weeks between the ages of 7-12 months. Leg preference was determined by the "lead-out" limb used as the infants pulled to stand from the half-kneeling position (half-kneel PTS). As a complementary measure, the leading leg during asymmetrical four-point kneeling and crawling ("asymmetrical four-point patterns") was used in the 10 infants who developed these patterns. The infants studied showed a general preference for using a leading leg during half-kneel PTS, which was mostly consistent over the study period. A strong correlation was found between leg preferences during half-kneel PTS and asymmetrical four-point patterns. The findings documented functional asymmetry in infant lower limbs during half-kneel PTS and asymmetrical four-point patterns, highlighting the importance of the tasks used to define leg preference.
