Excerpt volume: Illustrations from motor development of Siegler's "Overlapping Waves Model" of strategy choice

Siegler's "Overlapping Waves Model" proposes that strategies enter children's repertoires at different times and change in frequency over development as behavior becomes more adaptive and functional. Here, we illustrate the Overlapping Waves Model with video clips from several studies in infant and child motor development. (See links for specific papers relevant to the excerpts). Illustration #1: Infants' use of various strategies for descending impossibly steep slopes (backing feet first, sliding head first, sitting, crawling, walking, avoiding descent). Longitudinal observations show that strategies entered infants' repertoires at various ages and changed in frequency as infants became more accurate at detecting affordances for descent over weeks of crawling and walking. See links for Illustration #1-Longitudinal. Cross-sectional observations show that individual infants use multiple strategies within a single session. See links for Illustration #1-Cross-sectional. Illustration #2: Walking infants use multiple strategies for descending drop-offs (backing feet first, sitting, crawling, walking, avoiding descent). See links for Illustration #2-Drop-offs. Illustration #3: 4-year-olds use multiple strategies for pounding a peg with a hammer (radial grip, ulnar grip, two-handed grip, etc.). See links for Illustration #3-Hammering.