title: Constraints on arm selection processes when reaching: degrees of freedom and joint amplitudes interact to influence limb selection.
abstract: With an interest in identifying the variables that constrain arm choice when reaching, the authors had 11 right-handed participants perform free-choice and assigned-limb reaches at 9 object positions. The right arm was freely selected 100% of the time when reaching to positions at 30° and 40° into right hemispace. However, the left arm was freely selected to reach to positions at -30° and -40° in left hemispace 85% of the time. A comparison between free- and assigned-limb reaching kinematics revealed that free limb selection when reaching to the farthest positions was constrained by joint amplitude requirements and the time devoted to limb deceleration. Differences between free- and assigned-arm reaches were not evident when reaching to the midline and positions of ±10°, even though the right arm was freely selected most often for these positions. Different factors contribute to limb selection as a function of distance into a specific hemispace.
authors: Department of Physical Education, Health and Recreation, Prince Sultan University, Riyadh, Saudi Arabia.
authors: Wondae
authors: W
authors: Kim
authors: John
authors: J
authors: Buchanan
authors: Carl
authors: C
authors: Gabbard
mesh_terms: D001132:Arm / Q000502:physiology*; D001696:Biomechanical Phenomena / Q000502:physiology; D002755:Choice Behavior / Q000502:physiology*; D005260:Female; D006801:Humans; D007596:Joints / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology; D010775:Photic Stimulation / Q000379:methods; D011597:Psychomotor Performance / Q000502:physiology*; D055815:Young Adult