Building anticipatory postural adjustment during childhood: A kinematic and electromyographic analysis of unloading in children from 4 to 8 years of age

  • Schmitz C
  • Martin N
  • Assaiante C
  • 51

    Readers

    Mendeley users who have this article in their library.
  • 60

    Citations

    Citations of this article.

Abstract

The present study addressed the question of how do anticipatory postural adjustments (APA) develop during childhood, in the range from 4 to 8 years, during a bimanual load-lifting task. This task required maintaining the stabilisation of the forearm position despite imposed or voluntary unloading of the forearm. Elbow angle and multiple surface EMG were recorded on the child postural forearm supporting a load. During voluntary unloading, the elbow flexion of the postural forearm was calculated as a percentage of the elbow flexion measured during the imposed situation. Improvement of the forearm stabilisation was observed mainly between 4--6 and 7--8 years of age, but the oldest children did not reach the adult level of stabilisation of the postural forearm. Moreover, a clear developmental sequence in the acquisition of APA was reported: first the selection of an efficient EMG pattern underlying the forearm stabilisation, and second the mastering of timing adjustments. In fact, regression of the co-contraction pattern was observed with age, together with selection of the adult-like reciprocal pattern. Mastering of the timing adjustments of the reciprocal pattern, characterised in adults by a well-synchronised co-ordination between onset of the flexor muscle contraction of the manual arm and onset of the flexor muscle inhibition of the postural forearm, progressively improves during development. Moreover, these results suggest that the internal representation of the consequences of unloading on the forearm stabilisation, underlying anticipatory function during a bimanual co-ordination task, slowly build up during childhood.

Author-supplied keywords

  • Anticipatory postural adjustments
  • Bimanual co-ordination
  • Children
  • EMG
  • Kinematic

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text

Authors

  • Christina Schmitz

  • Nicolas Martin

  • Christine Assaiante

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free