Jeffrey J. Lockman

A Perception–Action Perspective on Tool Use Development

In this essay I argue for a new wave of research on tool use development. Advances in the literature on perception-action development hold important clues for how tool use unfolds in children. These advances suggest that tool use may be a more continuous developmental achievement than has been previously believed. On this view, tool use is rooted in the perception-action routines that infants employ to gain information about their environments. Although tools alter the properties of effector systems, children use tools to explore and change their environments, building on efforts that originate in infancy. Based on this approach, new research directions are suggested, including efforts designed to investigate the processes by which children detect and relate affordances between objects, coordinate spatial frames of reference, and incorporate early-appearing action patterns into instrumental behaviors.

The development of children's representations of large-scale environments.

HAZEN, NANCY L.; LOCKMAN, JEFFREY J.; and PICK, HERBERT L., JR. The Development of Childrens Representations of Large-Scale Environments. Cmum DEVELOPMENT, 1978, 49, 623-636. In an investigation of childrens spatial knowledge of a large-scale environment, 3-6-year-old children were taken through an environment by a specified route. Once the route and landmarks along the route were learned, children were tested on their ability to (1) travel the route in reverse (route-reversal knowledge), (2) name the sequence of landmarks along the reverse route (landmark-reversal knowledge), (3) infer the relationship between parts of the environment not directly traveled between (inference knowledge), and (4) construct a model of the environment. Results indicated that route-reversal knowledge develops before landmark-reversal knowledge, and inference ability develops last; the results also suggested that young childrens spatial representations are routelike and poorly integrated in comparison with those of older children. Furthermore, the results of the model-construction task indicated that the ability to coordinate knowledge of the route, sequence of landmarks, and shape of the layout may be a prerequisite for formation of an accurate spatial representation.

Going around transparent and grid‐like barriers: detour ability as a perception–action skill

Early detour ability may not generalize immediately across similar problems in different perception–action systems, but instead may reveal a pattern of developmental onset that is more domain-specific. To investigate this possibility, we examined how 10-month-old (n = 24) and 12-month-old (n = 24) infants performed detours via different action modes and around barriers that differed in transparency. Infants made reaching and locomotor detours to retrieve an object located behind either an upright transparent barrier or an upright transparent barrier overlaid with a grid pattern. The results indicated that infants were more likely to make reaching than locomotor detours and explored the transparent and grid barriers differently. Additionally, younger infants more often attempted to contact the object through the entirely transparent barrier than did older infants, especially when making a reaching detour. The results suggest that during detour development, infants learn to coordinate relevant perceptual information with emerging actions.

Change in imitation for object manipulation between 10 and 12 months of age

By the end of the first year, infants show dramatic increases in manual skill. In this study we tested one factor likely to contribute to this change: an increase in the capacity for observational learning, which may enable infants to learn new behaviors and practice ones that they already possess. Thus, we evaluated change in imitation between 10 and 12 months of age. Twelve 10-month-olds and twelve 12-month-old infants were shown different kinds of manual actions on a variety of objects; infants also manipulated objects during a free play control condition. Results indicated that older infants benefited more than younger ones in the Demonstration condition and that at both ages, infants performed the target action more quickly after observing a demonstration. We hypothesize that observational learning can help manual skill development by enabling infants to learn new actions and select and practice ones already in their skill set.

Object Manipulation in Infancy

Soon after infants begin to reach, they devote an increasing amount of time to manipulating objects. They finger, bang, and rotate objects often with great interest and delight. They do so in a variety of situations, whether it be in the context of solitary play or social interaction. Most parents, in fact, recognize this proclivity and tolerate it even in situations where similar behaviors by adults would be considered inappropriate. (Just imagine an adult banging a spoon on a table in a restaurant—even if service is slow!)

Development of Early Handwriting: Visual-Motor Control During Letter Copying

Despite the importance of handwriting for school readiness and early academic progress, prior research on the development of handwriting has focused primarily on the product rather than the process by which young children write letters. In contrast, in the present work, early handwriting is viewed as involving a suite of perceptual, motor, and cognitive abilities, which must work in unison if children are to write letters efficiently. To study such coordination, head-mounted eye-tracking technology was used to investigate the process of visual-motor coordination while kindergarten children (N = 23) and adults (N = 11) copied individual letters and strings of letters that differed in terms of their phonemic properties. Results indicated that kindergarten children were able to copy single letters efficiently, as did adults. When the cognitive demands of the task increased and children were presented with strings of letters, however, their ability to copy letters efficiently was compromised: Children frequently interrupted their writing midletter, whereas they did not do so on single letter trials. Yet, with increasing age, children became more efficient in copying letter strings, in part by using vision more prospectively when writing. Taken together, the results illustrate how the coordination of perceptual, motor, and cognitive processes contributes to advances in the development of letter writing skill.

When does tool use become distinctively human? Hammering in young children.

This study examines the development of hammering within an ontogenetic and evolutionary framework using motion-capture technology. Twenty-four right-handed toddlers (19-35 months) wore reflective markers while hammering a peg into a peg-board. The study focuses on the motor characteristics that make tool use uniquely human: wrist involvement, lateralization, and handle use. Older children showed more distally controlled movements, characterized by relatively more reliance on the wrist, but only when hammering with their right hand. Greater age, use of the right hand, and more wrist involvement were associated with higher accuracy; handle use did not systematically change with age. Collectively, the results provide new insights about the emergence of hammering in young children and when hammering begins to manifest distinctively human characteristics.

Perceptuomotor coordination in infancy

This chapter reviews and discusses recent research and thinking about infant perceptuo-motor coordination, according to the Piagetian and Gibsonian theoretical positions. Coordination within as well as across perceptuo-motor systems are considered. Developmental changes are examined in the following perceptuomotor systems: Oculomotor, vision and posture, auditory-motor, audition and prehension, and vision and prehension. In conclusion, future directions for research are suggested.

Manual action, fitting, and spatial planning: Relating objects by young children

This study uses motion tracking technology to provide a new way of addressing the development of the ability to prospectively orient objects with respect to one another. A group of toddlers between 16 and 33 months of age (N=30) were studied in an object fitting task while they wore reflective markers on their hands to track spatial adjustments in three dimensions. Manual displacements of the handheld object were separated into translations and rotations. Results revealed that younger children largely used a two-step approach in which they initially translate an object to a target and subsequently attempt to rotate the object to match the target. In contrast, older children evidence more advanced spatial planning and integrate translational and rotational components throughout the entire period when they are transporting the object to the target. Additionally, at the oldest ages, children show even further improvements in coordinating translations and rotations by using relatively shorter translations (i.e., covering less distance) and by avoiding unnecessary rotations of the object. More broadly, the results offer insights into how manual problem solving becomes more efficient and planful during the toddler years.

Building Tool Use From Object Manipulation: A Perception–Action Perspective

Tools are a universal feature of human culture. While most past research on tool use has focused on its cognitive underpinnings, in the present article we adopt a perception-action approach to understand how tool use emerges in early development. In this context, we review our work on infant object banging and how it may serve as a motor substrate for percussive tool use. Our results suggest that infants use banging to act on environmental surfaces selectively. Additionally, with increasing age, banging becomes more controlled and manifests many characteristics associated with skilled hammering. Taken together, the results suggest that there is much to be gained from considering the emergence of tool use as an ongoing process of perceptuomotor adaptation to handheld objects.