Related Experiment Videos
Effective action by infants to contact objects by reaching and leaning
B E McKenzie1, H Skouteris, R H Day
1Department of Psychology, La Trobe University, Bundoora, Victoria, Australia.
Insights
Infants as young as 8 months understand that leaning extends their reach. By 12 months, they learn to use tools to extend their reaching space, demonstrating developing motor control and spatial awareness.
Area of Science:
- Developmental Psychology
- Motor Control
- Infant Perception
Background:
- Understanding infant motor development is crucial for grasping early cognitive abilities.
- Coordinating arm and trunk movements is a key developmental milestone for infants.
Purpose of the Study:
- To investigate how infants aged 8-12 months coordinate arm and trunk movements to reach objects.
- To determine infants' perception of reaching space and the use of tools.
Main Methods:
- Two experiments were conducted with infants aged 8, 10, and 12 months.
- Infants' reaching and leaning behaviors were observed in response to objects at varying distances.
- A mechanical aid was introduced in the second experiment to assess its use.
Main Results:
- Infants as young as 8 months use leaning to extend their reach for distant objects.
- Ten-month-old infants perceive the limits of combined reaching and leaning.
- Twelve-month-old infants begin to utilize tools to expand their reaching capabilities.
Conclusions:
- Infants demonstrate an early understanding of how body movements extend their reach.
- Perception of effective reaching space and tool use develops progressively between 8 and 12 months.
- These findings highlight the development of integrated motor planning and spatial reasoning in infancy.
Abstract:
The ability of infants aged 8-12 months to coordinate their arm and trunk movements to contact an object located in different positions was investigated in 2 experiments. In the first, 8- and 10-month-old infants reached for near objects but both reached and leaned for more distant ones indicating that they perceived that forward leaning extends the range of contact beyond that of reaching alone. In addition, arm and trunk movements were initiated simultaneously; visual information concerning object distance was sufficient to activate an integrated reaching-and-leaning response. Object distances were increased and a mechanical aid was provided on half the trials in the second experiment with 10- and 12-month-old infants. For both age groups the degree of leaning was reduced for objects that were out of reach without the aid. Only older infants were able to use the aid to extend partially their range of contact. Overall the results support the conclusions that, by at least 8 months, infants perceive that leaning extends their effective reaching space; by 10 months they perceive the limits within which reaching together with leaning is likely to be effective; and by 12 months they begin to perceive how this space may be extended by a mechanical aid.