The quantitative measurement of motor mirror phenomenas in children at nursery age

The present study examines mirror forces under force tracking tasks in chil dren at nursery age and in adults in relation to force precision, maximum g rip forces, skillness and degree of hand lateralisation. 69 three to six-year old children and 17 adults without neurological abnorm alities were examined by two grip objects (hand grip object, 200 g, pinch g rip object, 20 g, each with uniaxial force sensors) with respect to mirror forces under different force tracking tasks. Further, three cases with cere bellar and spastic movement disorders were presented. In normal children, correlations were found between mirror forces (mean for ces=static component, coefficient of variation=dynamic component) and the p erformance of skill,the force precision, and to a lesser extent,also the de gree of hand lateralisation. The patients with movement disorders had marke dly increased mirror phenomena. Even Adults exhibited some mirror forces (e .g. the static component). The quantitative measurement of mirror forces under defined force tracking tasks may allow even in children at nursery age with their physiological mi rror phenomena a functional differentiation, and it may provide perspective s for further issues in motor diagnostics at an early age.