Alterations in Movement Dynamics in a Tool-Use Task

Zeitschrift für Psychologie/ …, 2012

This research evaluated how the inertial properties of a tool influence tool-using actions. Grip patterns and movements of 3-, 4-, and 5year-old children and adults were recorded while hammering. Results revealed that both number of pegs driven and movement amplitude increased developmentally and changed as a function of inertial properties of the tool but other aspects of motor control (i.e., period, grip position) did not. This suggests that both children and adults were able to discriminate and modulate only those parameters that had the largest impact on performance (i.e., the delivery of force with the hammer). Even though the ability to adjust tool movements as tool characteristics change is evident during preschool years, the ability to do so did not reach adult levels and appears to continue to develop beyond preschool.

Developmental Psychobiology, 2016

Hammering with a hand tool appears early in life. Skillful hammering involves accommodating movements to properties of the hammer, orienting the hammer's head to the item to be struck, and maintaining stable posture during forceful action with the arm(s). We aimed to characterize development of these abilities in young children (12, 18, and 24 months old). Children struck at a peg with a hammer held in the hand or a hammer attached to a handle. Children struck more frequently with a hard hammer surface than a soft one, and more frequently (although less accurately) with handled hammers than with non-handled hammers. Developmental differences were evident in accuracy, number of strikes, and kinematic parameters, especially with the handled object. Children's ability to use objects for forceful and accurate percussion changed measurably over the second year, in tandem with improving postural stability and greater motion of the elbow.

Child Development, 2020

An inherent component of tool-use actions is the transformation of the user's operating movement into the desired effect. In this study, the relevance of this transformation for young children's learning of tool-use actions was investigated. Sixty-four children at the age of 27-30 months learned to use levers which either simply extended (compatible transformation) or reversed (incompatible transformation) their operating movements. Data revealed a compatibility effect as well as transfer effects originating from the two different types of transformations. Furthermore, results suggest that young children's tool-use learning is not a uniform process, but has to be regarded individually depending on the type of transformation. We thank Manja Djordjevic and Lynn Pizzolato for their help with data acquisition and coding.

2019

We investigated how repeated, five-minute familiarization sessions occuring once a week over a 6-week period influenced 14 to 15 1/2 month-old infants’ ability to use a rake-like tool to retrieve an out of reach object. We found that infants, who were not allowed to touch the rake, but only to observe an adult retrieve an object with it, improved their performance. On the other hand, infants who were allowed to manually manipulate the rake and touch and move other objects with it did not improve their performance. The results, which were also replicated in a string-pulling task, suggest that cognitive rather than motor, limitations are mainly what prevent infants from succeeding in such tool-use tasks. Furthermore, infants can The Roles Of Observation and Manipulation In Tool Use overcome these cognitive limitations with only a few, very brief demonstrations spaced over several weeks. The Roles Of Observation and Manipulation In Tool Use

Ecological psychology, 2001

Whether an object can be used to satisfy a given tool user's intention depends on, among other things, the object's inertial properties. Overcoming an object's rotational inertia is key in controlling a handheld object with respect to a given intention. Manipulating an object by means of muscular exertion is the domain of dynamic touch. Thus, the affordances of a given object as a tool should be perceivable by means of dynamic touch. In 3 experiments, we investigated the inertial variables that support perception of 2 potential affordances of handheld tools: hammer-with-ability and poke-with-ability. The results suggest that ratings of hammers are dependent on the volume of the inertial ellipsoid in such a way that supports the transference of power to the struck surface. Ratings of pokers are dependent on the same quantity but in a way that supports controllability of the poking object. Additionally, results suggest that minimal experience in a given tool-using task may "tune" tool users to the inertial properties required of a given tool for a given function.

Advances in Child Development and Behavior, 2014

Tool-use is specialized in humans, and juvenile humans show much more prolific and prodigious tool-use than other juvenile primates. Nonhuman primates possess many of the basic motor and behavioral capacities needed for manual tool-use: perceptual-motor specialization, sociocultural practices and interactions, and abstract conceptualization of kinds of functions, both real and imagined. These traits jointly contribute to the human specialization for tool-using. In particular, from 2 to 5 years of age children develop: (i) more refined motor routines for interacting with a variety of objects, (ii) a deeper under- standing and awareness of the cultural context of object-use practices, and (iii) a cognitive facility to represent potential dynamic human–object interactions. The last trait, which has received little attention in recent years, is defined as the ability to form abstract (i.e., generalizable to novel contexts) representations of kinds of functions, even with relatively little training or instruction. This trait might depend not only on extensive tool-using expe- rience but also on developing cognitive abilities, including a variety of cognitive flexibility: specifically, imagistic memory for event sequences incorporating causal inferences about mechanical effects. Final speculations point to a possible network of neural systems that might contribute to the cognitive capacity that includes sensorimotor, sensory integration, and prefrontal cortical resources and interconnections.

2011

Recent imaging studies have found activation in areas associated with motion processing and motor planning during a range of cognitive tasks involving tools. This has led some researchers to conclude that motor information is central to the conceptual representation of tools. To explore this hypothesis, we used a two-alternative forced-choice task to examine whether children and adults use motor information to determine the extension of new tool categories. Adults, 5-year-olds and 3-year-olds were introduced to a novel tool ("a dax") and shown its function and how to manipulate it. Then two unlabelled tools were presented, one with the same function and one with the same motor manipulation.

Infant Behavior and Development, 1980

Two experiments were carried out to investigate the role of perceptual factors in the solution of tool-using problems by 9-10-month-old infants. In the first study, the infants were presented with seven different types of tools that varied in shape and in spatial contact with the same goal (a small fuzzy mechanical toy). The tools and the toy were either similar or different, in color and/or in texture. There were strong effects of spatial configuation across color/texture conditions. Color/texture interactions suggested that a similarity in both color and texture made the problems particularly difficult to solve. A second experiment was designed to separate the role of motor factors from the perceptual effect of spatial contact. On tool/goal combinations that were very similar in the motor skill involved, but distinguished by either a spatial contact or a small gap between tool and goal, the spatial contact items were significantly easier. The findings are discussed in terms of attention and memory processes in tool use, and the role of anticipatory imagery.

Cognitive Development, 2012