title: Power and precision grip force control in three-to-five-year-old children: velocity control precedes amplitude control in development.
abstract: The aim of this study was to examine the development of underlying motor control strategies in young children by characterizing the changes in performance of a visually guided force regulation task using two different grip formations; a whole-hand power grip (developmentally easier) and a thumb-index finger precision grip (developmentally more advanced). Typically developing preschool children (n=50, 3.0-5.5 years) used precision and power grips to perform a ramp and hold task with their dominant and non-dominant hands. Participants performed five trials with each hand and grip holding the force at 30% of their maximum volitional contraction for 3 s. The data were examined for both age-related and performance-related changes in motor performance. Across ages, children increased in strength, decreased in initial overshoot of the target force level, and decreased in rate of force release. Results of a cluster analysis suggest non-linear changes in the development of force control in preschool children, with a plateau in (or maturation of) velocity measures (rate of force increase and force decrease) earlier than in amplitude-related measures (initial force overshoot and force variability).
authors.affiliation: Department of Speech and Hearing Sciences, Washington State University, Spokane, WA 99210-1495, USA. nlpotter@wsu.edu
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Potter
authors.forename: Raymond D
authors.initials: RD
authors.lastname: Kent
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Lindstrom
authors.forename: Jo-Anne C
authors.initials: JA
authors.lastname: Lazarus
mesh_terms: D002675:Child, Preschool; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D009068:Movement / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*