Object Interaction and Walking: Integration of Old and New Skills in Infant Development

Abstract

Manual skills such as reaching, grasping, and exploring objects appear months earlier in infancy than locomotor skills such as walking. To what extent do infants incorporate an old skill (manual actions on objects) into the development of a new skill (walking)? We video recorded 64 sessions of infants during free play in a laboratory playroom. Infants’ age (12.7–19.5 months), walking experience (0.5–10.3 months), and walking proficiency (speed, step length, etc.) varied widely. We found that the earlier developing skills of holding and exploring objects were immediately incorporated into the later developing skill of walking. Although holding incurred a reliable cost to infants’ gait patterns, holding and exploring objects in hand were relatively common activities and did not change with development. Moreover, holding objects was equally common in standing and walking. However, infants did not interact with objects indiscriminately: Object exploration was more frequent while standing than walking, and infants selectively chose lighter objects to carry and explore. Findings suggest that the earlier appearance of some skills may serve to motivate and enrich later appearing skills.

Infant exuberant object play at home: Immense amounts of time‐distributed, variable practice

“…We thus wondered whether long bouts were qualitatively distinct in their content. Review of the 50 longest bouts across infants suggested that long bouts did not necessarily indicate “sophisticated object play.” Some long bouts were due to objects seemingly glued to infants’ hands (http://databrary.org/volume/1118/slot/44869/-?asset=294793) as when an infant walked around holding a snack cup or a crayon (Heiman et al, 2019). In other instances, long bouts involved play with multiple toys sequentially.…”

“…Based on prior home observations and free play in the laboratory, we expected both crawling and walking infants to accumulate large amounts of time interacting with objects (Karasik et al, 2011(Karasik et al, , 2012. Eleven-to 19-month-olds interact with objects about half of each hour, and they frequently carry objects to no recognizable end-destination and for no apparent reason (Heiman et al, 2019;Hoch et al, 2019;Karasik et al, 2011Karasik et al, , 2012. Although crawling infants are hampered in their ability to carry objects, crawlers can shift to sitting posture or pull to a stand to access and interact with objects.…”

Practice and proficiency: Factors that facilitate infant walking skill

“…Furthermore, experimental manipulations of infants' body dimensions directly affect walking skill. Infants display less mature walking patterns and incur more missteps and falls when wearing a diaper compared to walking naked (Cole et al, 2012), when wearing heavy pants compared to diapers (Theveniau et al, 2014), when loaded with small weights compared to unloaded (Garciaguirre et al, 2007;Vereijken et al, 2009), and when carrying objects compared to hands free (Heiman et al, 2019;Mangalindan et al, 2014). During free play, infants move less when loaded with 15% of their body weight compared to walking unweighted (Hoch, El Fadel, et al, 2019).…”

The ecology of infants’ perceptual-motor exploration

“…However, it is important to consider that acquiring new motor skills may not always be facilitative, especially in the short term. Crawling interferes with new crawlers' vocalizations [27] and carrying objects disrupts new walkers' balance [28].…”