Tool use can be considered a particularly useful model to understand the nature of functional actions. In 3 experiments, tool-use actions typified by stone knapping were investigated. Participants had detach flakes from flint core through conchoidal fracture. Successful flake detachment requires controlling various parameters simultaneously. Accordingly, our goals twofold: (a) examine regulation kinetic energy varying properties hammers and goal, (b) characterize difference in action across...

Abstract Skills involved in the knapping of Harappan long carnelian beads are studied order to assess their value as well knappers' socio‐economic status. by reference present‐day bead Khambhat, India. They examined from way actors able handle complexity task and achieve it. analyzed terms learning difficulties duration apprenticeship. The methodology followed is proper psychological field. It enables us understand, particular, necessary apprenticeship required for whatever culture which it...

This article describes developmental changes in gait velocity and relates these to parameters that index postural stability (step width lateral acceleration) two components of (cadence step length). Five children were observed longitudinally over a 2-year period after onset independent walking. Their range speed increased threefold the first 6 months walking then remained constant. In contrast, decreased approximately twofold. Whereas adults, cadence length contribute equally speed, when...

The present study is the first exploratory step of a larger investigation focusing on influence culturally-related caretaking practices motor development. Four Bambara infants between 4 and 23 weeks age were observed for two full days with paper-and-pencil event-recording technique video films. We took down infant's 'postural time-table', i.e., different spatial positions experienced during everyday life (prone, supine, sitting, standing...) postural adjustments required by maternal...

The aim of this paper was to study, from a developmental perspective, the transient phase gait during period between standing posture and achievement steady state gait, using temporal biochemical parameters. Eight children who had been walking autonomously for 90 200 days were observed. A total 64 sequences steps analyzed. sequence began with child still executed on large force plate. From determination instantaneous velocity center gravity results establish that, unlike adults, progression...

Stone tool‐use and manufacture is seen as an important skill during the evolution of our species recently there has been increased interest in understanding perceptual‐motor abilities underlying this skill. This study provides further information with respect to motor strategies used stone knapping. Kinematics striking arm were recorded expert novice knappers while producing flakes two different sizes. Using Uncontrolled Manifold Analysis, results showed that structure joint angle movements...

Various authors have suggested similarities between tool use in early hominins and chimpanzees. This has been particularly evident studies of nut-cracking which is considered to be the most complex skill exhibited by wild apes, also interpreted as a precursor more stone-flaking abilities. It argued that there no major qualitative difference what chimpanzee does when he cracks nut did they detached flake from core. In this paper, differences skills involved are explored through an...

We analyzed the relationship between goal achievement and execution variability in craftsmen who have acquired highest "ultimate" skills of stone knapping. The a knapping movement is defined as vector final velocity hammer, crucial for detaching flake and, consequently, shape product. by kinematic pattern arm (i.e., coordination joint angles corresponding to seven degrees freedom). results show that (a) direction very stable all craftsmen, whereas amount kinetic energy transmitted was...

The earliest direct evidence for tool-use by our ancestors are 2.6 million year old stone tools from Africa. These artifacts show that, already, early hominins had developed the required advanced movement skills and cognitive capacities to manufacture tools. Currently, it is not well understood, however, which specific successful knapping accordingly unknown how these emerged during hominin evolution. In particular, clear striking movements indicative of skilled performance, patterns vary...

Dexterous behavior exhibits exquisite context sensitivity, implying the efficacy of exploration to detect task-relevant information. Inspired by recent finding that fractal scaling exploratory movements predicts how well sample available perceptual information, we investigate possibility dexterity craftsmen would be characterized (long-range) temporal correlation properties fluctuations in their movement wielding a tool. A reanalysis hammering involved stone beads production India (Nonaka &...

As society ages and the frequency of falls increases, counteracting gait posture decline is a challenging issue for countries developed world. Previous studies have shown that exercise hazard management help to improve balance and/or decrease risks falling in normal aging. Motor activity based on motor-skill learning, particularly dance, can also benefit decreases with age. Recent suggested older dancers better balance, posture, or than non-dancers. Additionally, clinical laboratory measures...

Understanding the human aging of postural control and how physical or motor activity improves balance gait is challenging for both clinicians researchers. Previous studies have evidenced that sporting focusing on cardiovascular strength conditioning help older adults develop their and/or decrease frequency falls. Motor based motor-skill learning has also been put forward as an alternative to prevent falls in aging. Specifically dance advocated a promising program boost control. In this...

This study aims to determine whether the arm coordination observed at different stroke rates (SR, number of cycles per minute) differs according level expertise. Thirteen non-expert (G(NE)) and 14 expert (G(E)) swimmers swam crawl five 25-m lengths rate values: 35, 40, 45, 50, 55 cycles.min(-1). Results show that pattern 45 % G(NE) switched from catch-up (a lag time is performed between propulsive phases two arms) superposition mode (both arms pushing simultaneously during a short period...

Learning and context. Generally speaking we may consider that action refers to a goal the means necessary reach goal. It is then distinguish intentional aspect of -the -and functional it used Consequently skill be defined as capacity person in any circumstance using what environment offers. Any must negotiate environmental properties. This perceive something act upon necessitates construction Gibson (1979) called affordance. An affordance knowledge offers for action. Affordances are built up...