Learning to Crawl

Abstract

The effects of infants' age, body dimensions, and experience on the development of crawling was examined by observing 28 infants longitudinally, from children's first attempts at crawling until they began walking. Although most infants displayed multiple crawling postures en route to walking, development did not adhere to a strict progression of obligatory, discrete stages. In particular, 15 infants crawled on their bellies prior to crawling on hands and knees, but the other 13 infants skipped the belly-crawling period and proceeded directly to crawling on hands and knees. Duration of experience with earlier forms of crawling predicted the speed and efficiency of later, quite different forms of crawling. Most important, infants who had formerly belly crawled were more proficient crawling on hands and knees than infants who had skipped the belly-crawling period. Transfer could not be explained by differences in infants' age or body dimensions alone. Rather, experience using earlier crawling patterns may have exerted beneficial effects on hands-and-knees crawling by shoring up underlying constituents common to all forms of crawling postures.

First-person action experience reveals sensitivity to action efficiency in prereaching infants

“…On the strongest version of this view, the very notion that movements are directed toward goals may be learned from early first-person experience engaging in intentional action (27,28). At approximately 4 to 5 mo of age, infants begin to retrieve objects by reaching and grasping (29), and at 6 to 7 mo, they begin to locomote independently (30). By performing such actions, infants may learn that their own movements are driven by internal goals or desires, that the physical environment imposes constraints on those movements, and that they tend to achieve goals efficiently given the constraints of the environment.…”

Hand placement during quadruped locomotion in a humanoid robot: A dynamical system approach

“…Analysis of crawling infants have shown that most infants crawl on hands and knees, using a walking trot gait ( [15], [16]). This is a gait where diagonally opposed limbs move in synchrony and in anti-phase with the other limbs (trot gait) with a very high duty factor (proportion of the duration of the stance phase over one complete cycle), that is comprised between 50 and 70%.…”

A developmental view of the undernourished child: background and purpose of the study in Pangalengan, Indonesia

“…Myelination of efferent neural pathways in these areas is necessary for the onset of directed locomotion (Forssberg, 1985;Konner, 1991). Body size, body proportions and body mass along with muscle and bone strength affect the onset of locomotion (Gesell, 1939;McGraw, 1945;Thelen, 1984;Adolph et al, 1998). Brie¯y, the physics and engineering of the biological ± mechanical system play key roles in motor actions.…”