Teach to reach: the effects of active vs. passive reaching experiences on action and perception

Abstract

Reaching is an important and early emerging motor skill that allows infants to interact with the physical and social world. However, few studies have considered how reaching experiences shape infants' own motor development and their perception of actions performed by others. In the current study, two groups of infants received daily parent guided play sessions over a 2-weeks training period. Using "Sticky Mittens", one group was enabled to independently pick up objects whereas the other group only passively observed their parent's actions on objects. Following training, infants' manual and visual exploration of objects, agents, and actions in a live and a televised context were assessed. Our results showed that only infants who experienced independent object apprehension advanced in their reaching behavior, and showed changes in their visual exploration of agents and objects in a live setting. Passive observation was not sufficient to change infants' behavior. To our surprise, the effects of the training did not seem to generalize to a televised observation context. Together, our results suggest that early motor training can jump-start infants' transition into reaching and inform their perception of others' actions.

Copyright © 2010 Elsevier Ltd. All rights reserved.

Figures

Figure 1

Example of the Active- and Passive-Training procedures. a) Active Training (AT): Toys stick to the mittens upon contact and are moved by the infant. b) Passive Training (PT): Toys are moved by the parent and do not stick to the mittens.

Figure 2

Example of the four-step reaching assessment used in the live context. A small toy was sequentially placed I) beyond reach, II) far but within reach, III) close to hands at midline, and IV) placed into the infant’s hands. Each step lasted about 30 sec. This test was completed once on each lab and home visit. During home visits, a reaching tray as depicted in steps I–III was used.

Figure 3

Results of the reaching assessment in the live context for a) Step I – Looking duration to experimenter; b) combined Steps II and III – Reaching and grasping behavior; and c) Step IV – Separate looking at toy episodes. Longitudinal patterns are reported from the first lab visit (Lab 1), over up to 4 home visits (Home 1–4), and the second lab visit (Lab 2). Significant differences (p

Figure 4

Number of face-toy gaze shifts in the televised context. Untrained 3-month-old infants showed the least number of gaze shifts, untrained 5-month-old infants showed the highest number of gaze shifts. Both AT and PT groups fell in-between the younger and older untrained infants and showed similar amounts of gaze shifting. Error bars represent SEM. * p